Sea and River-side Rambles in Victoria/Chapter 5
CHAPTER V.
"Pale glistening pearls, and rainbow-coloured Shells,
Bright things that gleam unreck'd of."
Before again starting, our party is reinforced by some friends who desire to be initiated into the wonders of the Sea-shore, and we ramble along ancle deep in the sea water, now enriching our own vasculum, and now explaining to some of the younger of our companions the habits and construction of many curious things with which they load themselves. One of them gathers some very beautiful Echini (Sea Eggs or Urchins) to which the spines are still adhering, and we save some for microscopic examination since they are important in the identification of species, varying probably in each. We mentioned before, (page 9), the peculiar suckers of the Starfishes, and those of the Sea-eggs are very similar. The beautiful (so called) shell of this creature is but little known, or it would surely be more appreciated; it is composed of five pieces admirably joined together, so as to form its habitation, and is perforated at each extremity by two large openings, one of which is the mouth, from which project five polished pointed teeth, better adapted, we should have thought, for large Molluscs than a vegetable diet of Algae and Desmidise. The calcareous plates (which are more easily examined when the spines are rubbed off), may be divided into two sets, varying as well in shape as in their use,—the larger being studded with hemispherical tubercles of considerable size, attached externally to articulate with the moveable locomotive spines. Each of these large plates has somewhat of a pentagonal form, those situated near the mouth and apex being considerably smaller than those at the centre of the shell;—there are ten rows of these tuberculated plates, but being disposed in pairs, each row of large pieces being united by a zig-zag suture with another of a similar description, there are in reality but five large segments of the shell, each supporting a double row of tubercles. Nor are these the only parts to which spines are affixed, a vast number, though of secondary importance, being disseminated over the surface. In addition to the plates supporting the tubercles, there are a number of ambulacral bands which support the myriads of suckers protruded after the manner of the Starfishes. "In a moderate sized Urchin," Forbes tells us,[1] "he reckoned sixty-two rows of pores in each of the ten avenues." Now as there are three pairs of pores in each row, their number multiplied by six, and again by ten, would give the great number of 3,720 pores; but as each sucker occupies a pair of pores, the number of suckers would be only half that amount, or 1,860. In other parts its structure is not less complicated,—there are above three hundred plates of one kind, and nearly as many of another, all dovetailing together with the greatest nicety and regularity, bearing on their surfaces above 4,000 spines, each perfect in itself, of a complicated structure, and having a free movement in its socket,[2] We now come to the "Caves," which are the "lions" in this part of the country;—we enter the first, which has a double opening, high, but not particularly deep;—here, much to the joy of our party, we find magnificent groups of Purpuræ and Halotideæ (Ear Shells), and we were soon all on our knees intent in admiration of them, calling down vengeance on some irreverent beings who had been hacking and hewing away and mutilating many splendid specimens, without, as we could perceive, obtaining one entire. The Haliotis is a flat, brickdust coloured shell, so similar in shape to the human ear that it is commonly known as the Ear Shell; and the generic name given above is composed of two Greek words having a similar signification. The natives call it Munja, or big-mouthed. The aperture is nearly as large as the shell itself, one end being slightly spiral, and from the spire to the other extremity is a row of holes, for the passage of the animal's mantle, which are made at regular intervals as it increases in size, the one nearest the spire closing up as each new one is formed, leaving seven or eight generally open; the interior of the shell is beautifully iridiscent, and in much request for inlaying purposes. The animal itself is exceedingly worthy of attention, its head and side-lobes being fringed or festooned. The natives of the South Sea use the §hell to ornament their boats, and to make some kind of musical instrument,—the thick portions of the lip are also formed into fish hooks. Mr. Swainson[3] corrects a remark of Mr. Reeves in his Monograph on this genus, that "It is a curious. circumstance in the Geography of the Haliotideæ, that few, if any, are to be found where Chitons (Boat Shell) abound, as if they exchanged places to a certain extent in the two hemispheres -" and we have found as he has, that both these genera do inhabit not only the same latitudes, but almost precisely the same localities, the Chitons being common in the rock pools on the coast, the Haliotideæ remaining only in deeper water, feeding occasionally on shore vegetation.
The author of the "Curiosities of Food," mentions that the natives of most of the islands in the Chinese seas dry the soft parts of a species of this animal as an article of food.
It is here may be found, in some of the deep holes, that singular creature called the Pagurus, or Hermit Crab, from its invariably inhabiting the empty shells of some of the Mollusca; the body and tail are wanting the usual shelly covering, or possess it but in a rudimentary state, and have only a membranous bag for their protection. We well remember the surprise we felt on first beholding a specimen of this strange Crustacean which had been captured by a gentleman whilst Cray-fishing somewhere in this locality, and we were at first inclined to think it was undergoing the process of the periodical moult, after the habit of its kind, the new shell being only in a semi-developed state, but a careful search subsequently along the sea-shore revealed numerous individuals in the same rudimentary condition, ensconced generally in the water-worn habitation of the Fusus, or Spindle-shell, with in all the instances we observed, the protruded claw considerably longer and larger than the other, yet this may not be a permanent characteristic of the species.
So perfect is everything which has been created, that we naturally ask ourselves the question, how may this seeming defect be accounted for; was the crab so created originally, or has this practice (as Mr. Lewes suggests[4]) resorted to at the outset as a temporary refuge from more powerful enemies, now become an organised tendency in the species? It is not easy to conjecture, but we incline to the opinion of Mr. Kirby,[5] that this singular form and habitation enables these uncouth animals to prey on creatures, which were they to wear the livery of their own tribe would be on their guard and escape them. We find too, that to adapt themselves thoroughly to their dwelling place, what in other species would be the tail, is in them transformed into an apparatus by which a firmer grip of it is obtained, and so carried more easily along whenever they take their walks abroad for pleasure or from necessity.
Whilst groping about in shallow water not many days since for the green Algae which grow attached to the rocks, an object moving freely about,—apparently vegetable,—arrested our attention; it was speedily captured and taken home inter alia, but so thickly was it covered with small fragments of red Algæ, and the violet colored zoophyte, Catenicella aurita, that it required long and very careful examination before we discovered that it was a small crab, which had evidently so disguised itself the better to obtain its prey. We were unable at the time to refer to our books to decide the species which had adopted this plan, and rapid decomposition set in subsequently, so that to this moment we remain in ignorance; but a writer of a paper in Volume 8 of the "Naturalist," (1858, page 7), called "Notes on Crustaceans," mentions having observed this peculiarity in crabs of the genus Hyas; and in one instance he was amused at seeing a fine fellow stalking along with all the majesty which borrowed plumes often produce;—it was in a large deep pool round the edge of which abrupt rocks stood, one affording a shelter for some very fine tufts of Delesseria sanguinea, amongst which he had established himself; but noticing, no doubt, that the color of his shell was an unpleasing contrast to the handsome weed, he proceeded to array himself with small bits of the extremity of the frond, which he detached, and stuck upon his carapace in an extremely irregular manner, giving him a most ludicrous appearance. This author had another opportunity of observing this process in a specimen which he had in his Aquarium.
But we should not omit to say a few words of the Birds of the Sea-shore, since they tend so much to our enlivenment—we could not forget them if we would: there are first the Gulls, ever restless, screaming their shrill note now just over our heads, and anon flying far out to sea in search of food, in the choice of which they do not seem very particular, preying greedily upon Fishes, Crustacea, Mollusca, and almost any carcase which is floating. When in search of food they sustain themselves, as many of our readers may have observed, by a quivering motion of the wings, now and then touching the water with their feet,—they swim well but cannot dive: then we have that splendid fellow the Swallow-tailed Tern, with his long red bill, jet black pate, and pale dove-colored wings, darting down into the sea after his prey with unerring accuracy and the rapidity of an arrow. Tripping nimbly along to the water's edge is the elegant little Dotterel, one of the most graceful of our sea-shore birds, and occasionally the Penguin will glide out from shelter of some seaweed bank; the Ibis is a common visitor to the Hopkins, as is also the splendid Australian Pelican, whose wings expand to a width of eight feet; the White-headed Fish-hawk or Osprey too may often be seen lurking about the rocks, feeding on some fine fish, captured by means of his spine-covered feet; the Cormorant frequents the rivers near the sea, and it will afford the sea-side stroller much and lasting pleasure to carefully watch the habits of any one of them, which he may easily do by concealing himself behind any low scrub or rock that presents itself.
- ↑ British Star Fishes, p. 152.
- ↑ "The Spines are at first immovable, and stand out like processes from the tubercles; the joint is not developed until after they have acquired a certain size." Owen's Comparative Anatomy, Invertebratæ," p. 201.
- ↑ Proceedings Royal Society of Van Diemen's Land, Vol. 3, part 1, January, 855, page 46.
- ↑ "Seaside Studies," page 47.
- ↑ "History, Habits, and Instincts of Animals." Bridg. Treat.