The Zoologist/4th series, vol 4 (1900)/Issue 710/Zoological Notes from Sydney, Stead 1900

by David George Stead

 

 

NEPTUNUS PELAGICUS M. Edw.

 

 

THE ZOOLOGIST

 

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No. 710.— August, 1900.

 

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ZOOLOGICAL NOTES FROM SYDNEY.

By David G. Stead.

(Plate IV.)

 

Last year (Zool. 1899, p. 407) I had the pleasure of narrating one of my zoological wanderings near Sydney. On the present occasion I propose to describe some of the objects of interest which it has been my good fortune to encounter on various rambles during the past few months.

At the time of writing the "bush" is teeming with animal life, chiefly insects, though the Reptilia play no small a part. Of the former, perhaps the Cicadas attract most attention, both by numbers and noise. It is only a few weeks since they made their appearance above ground (that is, in the city and environs), but they have been making the most of their time; and now the first thing to greet one's ears on awaking in the morning is the sound of their stridulation. Hot, still, sultry weather always suits them best, and under such atmospheric conditions, and as the season advances, they may be often heard long before daybreak, keeping up their "churr-urr-urr-urr" until about 7 or 8 o'clock, when there will be a general quietude until about 11 o'clock, when once more the concert is resumed with renewed vigour. This goes on with a few intermissions until about 4 or 5 p.m., when once more it ceases as suddenly as it began; only to start again about 7 p.m., and continuing until long after darkness has set in. I have even heard them as late as 11 p.m. I have spoken of the Cicadas as "singing." To me it is music (though most people consider it a hateful sound), recalling, as it invariably does, so many happy hours spent in roving about the bush. But even I can have too much of it. I can well remember one such occasion. It was a glorious day, with a gentle breeze and a blue sky, with the air clear and bright, when I sallied forth, making my way to the ferry which traverses that long arm of Port Jackson known as Parramatta River. I soon found plenty to interest me, as the water was in parts almost alive with Discomedusæ of several species, some small transparent ones (of a bluish tint) floating lazily along at the surface; others (Crambessa), of a large size and fleshy-pink colour, forging along steadily by means of the rhythmical contractions of their ciliated discs; and others, again—"man-o'-war blubbers"—which especially attracted attention on account of their beauty. These last are of a semi-transparent red tinge, the disc having all over its surface large white spots. These spots become very dense near the margin, the fringe being almost entirely white. (Recently—Feb. 4th, 1900—I observed a large number of these animals in Circular Quay, Port Jackson. Some of them had been greatly mutilated by the propellers of the many ferry-boats which ply from here. In one instance I observed a specimen swimming along serenely minus its manubrium, while in another there was only three-fourths of a disc, and this still contracted rhythmically.) From the borders of the disc depends, besides the usual short fringe, a large number of long white and beautiful, though treacherous, tentacles (these being thickly studded with lasso-cells). When swimming in clear water the animal possesses a most pleasing and beautiful appearance; but when one's limbs come into contact with its tentacles, as while wading, the most intense and painful irritation is set up, which lasts for some considerable time after (as I know to my cost).

After travelling a few miles I landed at my destination—Ryde, a pretty little village situated in a fruit-growing district. Several hollows in this locality are a great breeding-ground for three or four species of Cicada, notably one—Thopha saccata—a large species. That day I heard such a tumult of insect-life as I have never experienced either before or since. The noise was deafening. Some men who were near at hand, upon seeing me searching about amongst the stones, evidently guessed that I was on the look-out for zoological specimens, as they drew towards me, one of them carrying a magnificent green glittering beetle. He had to come quite close and shout before I could hear him, so tumultuous was the sound. All around on the trees (Eucalyptus), which were here tall and slender, were to be seen scores upon scores of Cicadas^[1] in all imaginable stages—dingy sluggish larvæ that had just emerged from their holes at the foot of some tree, some of them just in the act of bursting from the larva-case; others, again, that had performed this act, standing or climbing slowly up the tree, waiting for their wings (which were hanging like little green globular bags full of fluid) to dry; and so on up to the beauteous-winged imago flying lightly from tree to tree. In dealing with these insects one cannot fail to notice the habit they have of spurting an acrid fluid as they fly off on being alarmed; this they eject with some degree of force, and in considerable quantity.

My attention was here attracted by the great number of large handsome red-and-black Hymenoptera (Exeirus sp.?), which were attacking the Cicadas, relentlessly pursuing them from tree to tree. (Afterwards, on my road home, I came across a specimen of this large Wasp, hard at work dragging a large green and apparently anæsthetized Cicada across my pathway. Unthinkingly I separated them, for which I was immediately sorry, as I might have witnessed the performance of stowing the Cicada away in some hole for the use of its assailant's future progeny.)

Here also I observed large numbers of the Coleoptera known as "Elephant insects" (Curculionidæ) of two varieties, one of a uniform dark colour, and the other black and green, both kinds (Chrysolopus spectabilis, Fabr.) being on the branches of a large wattle-tree (Acacia). These wattle-trees are usually swarming with insects, notably Ants, on account of the large amount of gum which is exuded, especially from where there has been a wound. Here the vibration set up in the air by the Cicadas became so intense and so intolerable that I took to my heels, and made for the beach, so that I might gain a brief respite.

All along the shore were numbers of boulders which had been perforated through and through by the little Isopod crustacean Sphæroma, assisted here and there by a boring mollusc. These little creatures form a very powerful factor in the disintegration of the rocks, as, after they have driven their galleries through, it is quite an easy matter for the sea to do the rest. As commensals in the burrows of these Isopods, I have observed many other small crustaceans, several species of small fishes, including the Common Eel (Anguilla australis), and also a brown-coloured Araneid. This last—of which individuals were numerous—remains in the burrows even when the tide rises and floods them, and it may be seen moving about beneath the surface clothed in a tunic of air-bubbles.

While speaking of the seashore, I must mention something connected therewith which at once claims the naturalist's attention, and that is the zones which each animal (or set of animals) occupies. Taking a typical flat, and starting from the top, we would first come to a sandy zone, slightly above high water. This is inhabited by the beautiful "Swift-footed Crab" (Ocypoda cordimana), a small grey Isopod; and, in the event of there being decaying animal or vegetable matter, many specimens of the Common Sandhopper (Talorchestia quadrimana). Then, lower down, there is a zone just lapped at high water, about which are strewn clean stones (i.e. stones not overgrown with Algæ). Under these stones are to be found many interesting and exceedingly agile Crabs (Cyclograpsus Lavauxi). Going still lower, we come to a belt consisting of a mixture of sand and mud. On—or rather in—this we find the bright-coloured, martial-looking "Soldier Crab" (Mycteris longicarpus),^[2] and an exceedingly fragile Callianassa. Going beyond this again, we arrive at a zone which is only just above low-tide mark. This is composed of dark evil-smelling mud, with occasionally small Algæ-covered boulders strewn sparsely over its surface. On the stones themselves (amongst the Algæ) we find some tiny Crabs (Hymenosoma varium and Porcellana dispar). Underneath will be found others and larger species, viz. Chasmagnathus lævis, Sesarma erythrodactyla, and occasionally Pilumnopeus serratifrons. In the mud itself are two species: Helœcius cordiformis and Macrophthalmus setosus; besides several kinds of Annelida. The last-mentioned Crab—Pilumnopeus serratifrons—I have found, is occasionally attacked by a parasite—Sacculina.^[3] The parasitized Crabs which I examined were found to represent both sexes in about equal proportions, and neither the pleons nor the abdominal appendages were affected in either sex; a different state of things to that recorded by Prof. A. Giard in the case of certain European Crabs^[4] attacked in a somewhat similar manner; and also by Prof. W. Haswell in that of an Australian species—Nectocarcinus integrifrons.^[5]

I have spoken of Ryde as being in a fruit-growing district, which reminds me of the Fruit-Bats (Pteropus poliocephalus) . These are perhaps the orchard's greatest enemies. The fruitgrowers of the north-western suburbs of Sydney (of which Ryde is one) have annually large quantities of fruit destroyed by these "Flying Foxes," which congregate in immense numbers during the fruit season (the present time). After a night's ravaging they mass in great numbers in the heavy timber of the surrounding bush, and may be seen hanging thickly, almost like Bees, from the tree-branches. A war of extermination is waged against them periodically by bodies of fruit-growers. Recently, in pursuance of that custom, a party of fifty-three fruit-growers from the surrounding districts drove to a known camp of the pest, carrying with them 5000 cartridges. The number of "Flying Foxes" was estimated to be between 100,000 and 120,000. A successful raid was made upon the "camp," resulting in the destruction of about 2750 animals. In another district one hundred miles north of Sydney, at a recent battue, twenty men killed 13,000 of the same animal, which proves what a serious pest this Pteropus is to the orchards; as, for every peach, nectarine, or plum that the "Flying Fox" bites, it knocks down at least a dozen.

On two occasions recently we have had, on the coast of New South Wales, the most unusual phenomenon of a dust-storm at sea. A steamer on the way from Queensland to Sydney had a peculiar experience on the passage down the coast. After leaving Brisbane, and when crossing Moreton Bay, a thick haze was encountered, which made the atmosphere so dense that it was impossible to discern the leading lights. In consequence the vessel had to anchor from midnight till 5.30 a.m., when she passed out of the bay, the buoys in the channel being made out with difficulty, even though it was daylight. This continued for some distance down the coast. When the boat emerged from the thick weather everything (including the passengers' quarters and fittings) was covered with a fine red dust which had been carried out to sea by the strong westerly wind then blowing off the land. (Apropos of this, I am informed by Capt. Waller, who travels between New Zealand and this port, and to whom I am indebted for some interesting specimens which I hope to mention on some future occasion, that he has encountered moths and other insects whilst quite out of sight of the land, at a distance of from seventy to eighty miles from the New South Wales coast.) The red dust, upon undergoing a microscopical examination, was resolved into the remains of innumerable Diatomaceæ, a fact interesting alike to the zoologist and botanist.

While walking along the beach at Maroubra Bay (a few miles from Sydney), on an excursion some time ago, my attention was suddenly riveted by a very curious-looking object. This on close examination proved to be the fruit of Barringtonia cupania, which had evidently been in the water for some considerable time, as it was covered with stalked barnacles (Lepas pectinata?), some of which were apparently full-grown. Upon its surface was also a species of Bryozoa. In one corner a hole had been excavated (whether by its occupant or not, I am ignorant), and safely ensconced in it was the small and widely distributed "Gulf-weed Crab," Nautilograpsus minutus. (For those readers who are not familiar with this branch of zoology, I may add that this famous little crustacean is believed, with good reason, to be the one which Columbus found on the floating "Sargasso Weed," and which caused him, fallaciously, to surmise that his ships were near land. However, it is perhaps almost needless to say that this was no proof, as the animal is found in nearly all the tropical and temperate seas of the globe upon floating seaweed and wood.) In the same cavity as the Crab was a small "Sea-Mouse"; also in parts, where the husk was beginning to disintegrate, were several small brownish-black Amphipoda. The discovery of this current-borne Barringtonia is not by any means a unique one, though perhaps the finding of so many tenants is, as cocoa-nuts and other objects of interest are continually being found along our coast, which have been brought from the same far-distant source—the South Sea Islands. I have many times collected, at different points along the coast of New South Wales, small pieces of pumice and volcanic cinders. These have been continually washed up for a considerable number of years at least, as is amply borne out by the fact that they are found deep down in the grass-grown sand-dunes, whenever an opening is made (artificially or otherwise). The most interesting thing to the zoologist is that this flotsam carries with it occasionally—as I can personally bear witness—such animals as tubicolous annelids, and sometimes small specimens of coral. It is almost impossible to conceive what vast changes might be wrought, or what additions might be made, to the fauna or flora of an island lying in the course of the current which carries along this flotsam.

While on this subject I might mention some other ways by which Polynesian animals are transported to our waters. It will at once be self-evident that ships' bottoms are a very fertile agency, as there is a large amount of trade between this port and the islands of the South Pacific. Thus it is not very hard to understand how it is that fairly large specimens of Madrepores should have been found growing in Port Jackson, where they were certainly not pre-existent. Now, turning to the land-animals: our imports from the South Seas consist mainly of copra, pine-apples, bananas, cocoa-nuts, palm-leaf fans, hats, and native matting, and each of these brings along its quota of migrants. I had at one time brought to me a prettily marked Snake, alive, which was curled up in a bunch of bananas, and others have occasionally been found. But the three last-mentioned articles should perhaps claim priority for the number of Arthropoda—in the way of Cockroaches, Spiders, Centipedes, small Coleoptera, &c.—which they bring. On the other hand, I have reason to believe that many animals have been introduced from this country into the islands by means of the same agency—the ships.

During last year (1899), on several of my excursions round about Sydney, in walking over the heights, I was much struck by the curious appearance of the rocks (sandstone), which were in many cases completely honeycombed. As I am always exceedingly inquisitive about holes, I determined to "get to the bottom" of the cause. Upon making enquiries amongst my naturalist friends, I found that many others had noticed it, and it had been the subject of a considerable amount of controversy. Most seemed to favour the hypothesis that it was the work of Wasps, but a few clung to the view that it was done by the Termites. After a considerable amount of labour, I found that the tunnelling was the work of the latter insects, as I found them in situ and at work.^[6]

 

 

It would seem almost incredible that these little frail-looking creatures should accomplish such work as this, were it not for the fact that their depredations in houses, &c, are so well known. It was only quite recently that the weighty and apparently solid roof of the Australian Museum at Sydney was found to be in places completely honeycombed by these insects. In the course of their work they had actually bored through sheet-lead an eighth of an inch in thickness. Had the roof collapsed there would have resulted irreparable damage. The holes in the before-mentioned sandstone are beautifully uniform in size, are of great symmetry, and are lined in the manner so characteristic of the Termites. While speaking of excavations, it might not be amiss to mention another instance. One day I was out in the vicinity of Curl Curl (near Sydney), when I suddenly observed half-way up the stem of a young eucalypt a very round hole—in fact, it was the great symmetry which chiefly attracted my attention. Upon breaking down the stem, and cutting very carefully, I found the workmen within—the beautiful Carpenter Bees (Lestis æratus). Now, the most interesting part of this, is, that it points to an aberration of habit, in accordance with which these Bees usually burrow into the flowering stems of the "grass-tree" (Xanthorrhœa). Did they mistake this small stem—of the same thickness as a grass-tree stem—for the Xanthorrhœa? With about half the labour involved in cutting the eucalypt, they could have burrowed three times as far in the Xanthorrhœa.

Some time ago, while I was on one of my periodical trips to my happy hunting-ground—Manly—I was turning over the stones on the border of the bush above the shore, when, amongst other things, I came across several specimens of a large Millipede (Julus). This Millipede has a row of orifices along each side, one in the middle of each somite, from which, when irritated, it ejects a brownish-coloured fluid (in appearance much resembling iodine), which possesses an exceedingly penetrating pungent odour, very irritating indeed to the mucous membrane lining the nasal passages. But the supply of this fluid—which, scarcely without doubt, is for purposes of defence—seems to become very soon exhausted, as, after I had kept the Arthropods for a short time, scarcely any of the former odour was perceptible. Under this same stone I found specimens of a beautiful little Lizard (Lygosoma æquale), having very short, almost rudimentary legs, and truncate, though long, tail.

A little farther along this shore is a large rock-pool, which I often visit. In it I made rather a unique discovery in the shape of a specimen of the Gastropod Hydatina physis in the act of oviposition. The animal itself is beautiful, but the spiral ribbons of eggs, embedded as they were in a transparent jelly-like protoplasmic substance, were, in point of intrinsic beauty, equal to anything that I have ever observed. Molluscan ova are, of course, often to be met with; but unfortunately, in very many cases, without any satisfactory clue to the species to which they belong. In the present instance, however, there could be no doubt whatever. My friend Mr. Charles Hedley, F.L.S., of the Australian Museum, informs me that they much resemble an Aplysia figured by Rang.

On another occasion, when at Manly, while walking along, I was very much struck with the conduct of an Ant. It saw me at the distance of a few paces. The insect was carrying what I thought to be a green leaf, but what turned out to be a comparatively large larval "Grasshopper," several times the size of its bearer. The Ant seemed to become very excited, twisting round from side to side, looking at me all the time, and holding its prey up as high as it could. It appeared as if it were challenging me to come on (which I did), and when I tried to effect its capture it dropped its burden, and made several quick springs in my direction, leaping from five to six inches at a time. Whenever I moved to one side my little antagonist followed my motions with its eyes in the same manner as does the Mantis. It looked, indeed, so uncommonly human in its actions that when I captured it I had quite a large amount of respect for it.

One morning I went to Mosman's Bay (Port Jackson), and walked from thence along the harbour coast. After walking for some distance, I observed two fishermen about to haul in their net; so I went out with them in their boat, and assisted in the unloading of the net. It was a poor haul (i.e. looking at it from the fishermen's point of view, but not from the naturalist's), consisting as it did almost solely of small Discophoræ and immature pelagic Crabs (Neptunus pelagicus (Pl. IV.) and N. sanguinolentus, Thalamita sima, Charybdis cruciatus, and Nectocarcinus integrifrons). There were a few specimens of Squilla lævis, also of the handsome Prawn Penæus canaliculatus, and of the smaller and commoner Prawn P. esculentus. There was also a goodly number of species of small fishes, the most noticeable of which were the "Fortescues" (Pentaroge marmorata), and two specimens of the "Stink Fish" (Callionymus curvicornis). The first mentioned is a harmless-looking little creature, but in reality it is just the reverse. It is armed on each side of the head with exceedingly sharp spines. When the poor unsuspecting mortal picks up one of these carelessly, it whirls round its head suddenly, and the spines inflict a wound of a very painful nature. I captured several of these, however, without being injured. Whilst thus engaged I noticed a most noisome odour arising. While I was still wondering whence this was proceeding, one of the fishermen quickly settled the point by placing one of the last-mentioned fishes under my nose. I can assure the reader that I did not allow him to keep it there many seconds. It is a most objectionable stench, and would, in the writer's opinion, serve no doubt to restrain many other fishes from preying upon this one. In general appearance the fish is not unlike the "Flathead" (Platycephalus fuscus), but the mouth is very considerably smaller. I found that the odour was given off from two orifices at the back of the eyes, one on each side of the occiput.

I have no doubt that the story of the's.s. 'Perthshire' will be fresh in the memories of some readers at least. The vessel, while on a five days' voyage from Sydney to the Bluff (N.Z.) during last year, broke down, and was helplessly adrift at the mercy of the elements for a period of five weeks. While she was lying disabled on the 5th of May, about five hundred miles from the nearest land—Cape Howe, N.S.W.—a common "Bronze-wing Pigeon" (Phaps chalcoptera) flew aboard in an exhausted condition. The alighting of land-birds on ships close in shore, when the vessels are "making the land," is not an uncommon occurrence; but that a Bronze-wing Pigeon should have found a haven on a disabled vessel five hundred miles from the nearest land is indeed singular. This Pigeon is a short-flight bird, and, although it travels long distances during the hours of a long summer's day, it does it with frequent rests. How then did this hapless Bronze-wing manage to keep up over the five hundred miles of storm-tossed sea until it reached the vessel? The flock Pigeons of the far west and interior, which come periodically in countless thousands, are tireless flyers, at times coming in such swarms that at a distance they appear like a drifting cloud; then for a year or two they are entirely absent. One of these last-mentioned birds would have negotiated the distance (especially with the strong westerly wind behind it, which was blowing from the land at the time, and had been blowing for some days) with little difficulty. The marvellous thing is that a Bronze-wing should have done it; about the least likely species of Pigeon to attempt the feat—willingly! When I saw the bird it looked very well, and none the worse for its adventures.

Before finishing my notes on this occasion, I would like to mention one more incident. While out in the vicinity of North Harbour (Port Jackson), on Jan. 1st, 1900, I made a few observations which I hope to be able to speak of on some future occasion; merely relating one of them at present. I was situated in a very pretty little nook of the harbour called Pirate's Cove, and, as atmospheric conditions were favourable, waited till night came on. I was well repaid, for, upon darkness setting in, I found that the whole of the water flooding the cove was filled with myriads of the Noctiluca miliaris. Here and there the wake of some fish might be traced out in silver. Then every ripple on the water was crested with light; scattered plentifully between these were little individual globes of light, and as each wavelet plashed up on the rocks or sand it would leave many Noctilucæ stranded. Wading in until the water was over my knees, my nether limbs suddenly became clothed with phosphorescence. As there was no moon, the whole contrived to form a most beautiful and fascinating display of Nature's pyrotechnics.

While on the subject of phosphorescence, I may mention that, while walking along Jarrah Beach (Botany Bay) recently at night time, my attention was attracted by the number of little "orbs of light" which were being washed in. At first I thought it was the Noctiluca, but, upon handling one, I perceived that it was hard to the touch, and therefore came to the conclusion that it was an Ostracod crustacean; nor was I mistaken, for, upon examining it when I arrived home, I found that it was a species of Cypridina. When first I handled one of these it gave out a most brilliant greenish light; in fact, so strong was it that I was enabled to tell the time by my watch, the whole of the dial-plate, including the "second" marks, being visible. Though I have kept the animal alive since in a bottle of sea-water, it has not emitted any more light.

While continuing our walk the same evening, my companion and myself came upon some fishermen who had just drawn in their net. It was loaded with fishes—principally small "Mullet" (Mugil), though there was a somewhat varied assortment of others. As usual, there were amongst them a few "Cat-fishes" (Cnidoglanis megastoma). In feeling amongst the fishes in a net one had to be very careful not to come into contact with these animals. They have a most repulsive appearance, but this is not all. Amongst the cirrus which surrounds the mouth are spines covered with a poisonous mucus. This mucus causes the most severe pain when introduced into the system. My attention was here drawn to a sharp coughing sound, which I found proceeded from two specimens of the "Fiddler" Ray (Trygonorhina fasciata). Botany Bay is a great place for many species of Sharks, Kays, and other Flat-fishes. One Ray was procured from that locality which measured fifteen feet from "wing" to "wing."

What a hideous monster is human ignorance! We have in this city bubonic plague (Pestis bubonica). In some of the factories hundreds of workmen have destroyed their dinnerbaskets. One may well ask, "What connection is there between dinner-baskets and plague?" None whatever. That is to say, not any more than there might be with hundreds of other articles in daily use. The reason of their destruction is as follows:—Some of the men have discovered in their baskets the larvæ of the beetle which attacks this kind of ware. The beetles were there all the time, but the men had "no eyes to see" till they became possessed of the plague scare. As they did not know what the larvæ were, they came to the conclusion that their occurrence in the baskets must have something to do with the plague. Speaking of ignorance reminds me that I once observed an itinerant microscopist exhibiting to a wondering crowd a small bottle containing small fresh-water crustaceans of the genus Cypris, but he informed them that the animals were—Hydatids. Returning to the plague. As a consequence of our visitation by this dread enemy, an enormous amount of disinfectant has been poured daily into our drains and sewers. A great quantity of this has found its way into some of the bays of our harbour, and it has had the effect of asphyxiating thousands of fishes. The presence of all these fishes floating at the surface forms a unique and most unpleasant spectacle.

 

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Explanation of Plate IV.—Central Figure.—Neptunus pelagicas, M.-Edw.; mottled variety. Upper Central Figure.—Tubercular-setose variety. Left-hand Figures.—Upper: Dwarfed cheliped. Lower: Pleopoda. Female; sterile female; male. Central Lower Figure.—Masticatory organs. Right-hand Figures.—Upper: Sternal aspects: male; sterile female; female. Lower: Male; female; sterile female.

 

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1. These consisted chiefly of five species:—Thopha saccata, Psaltoda mœrens, Cicada angularis, Tibicen curvicosta (this makes a tremendous noise, and can be heard at a great distance, though it is not very large), and, lastly, Cyclochila australasiæ, of which there are two varieties, one a beautiful green, the other yellow, with intermediate forms.
2. For further information regarding these crustaceans, cf. author's "Notes on the Habits of some of the Australian Malacostracous Crustacea" (Zool. May, 1898).
3. Cf. my "Contributions to a Knowledge of the Australian Crustacean Fauna. No. 2. On Sacculina parasitic upon Pilumnopeus serratifrons" (P.L.S., N.S.W., part iv. 1899).
4. Ann. Mag. Nat. Hist. (5), vol. xix. pp. 325–345, 1881.
5. P.L.S., N.S.W. (2), vol. ii. 1888.
6. P.L.S., N.S.W., part iii. p. 418, 1899.