The Zoologist/4th series, vol 2 (1898)/Issue 688/Notices of New Books
NOTICES OF NEW BOOKS.
This volume, written by a well-known Cambridge zoologist, appeared opportunely a little before the meeting of the Zoological Congress at that University town. It is a classification of the Vertebrata based on the sound foundation of that which preceded as well as that which exists. It of course naturally follows that the osseous structure is all that we certainly know of the past vertebral life, though Dr. Gadow argues "it would be pedantic to exclude all soft perishable parts on the plea that they are unknown in the fossil forms. Here discretion is to be used. We do not 'know' that the palæozoic Fishes did possess an entirely venous heart, nor has it yet been shown that the embryos of Dinosaurs were surrounded by an amnion; but we feel nevertheless certain, because of the laws of correlation which comparative anatomy allows us to deduce from the study of recent creatures." This proposition will be generally accepted, and is distinct from the question of antecedent colouration, a subject still in the domain of probabilities. This method will perhaps be best exemplified by reference to our own relationships, which Dr. Gadow thus arranges:—
- "Anthropoidæ.—Caudal vertebræ transformed into a coccyx. Walk erect or semi-erect.
- Hylobates.—S.E. Asia. 'Gibbon.'
- Pliopithecus.—Miocene of Europe.
- Simia satyrus.—'Orang Utan.' Sumatra and Borneo.
- Troglodytes gorilla and T. niger.—West Equatorial Africa.
- T. sivalensis.—Pliocene, Punjab.
- Dryopithecus.—Miocene, France.
- Pithecanthropus erectus.—Plistocene, Java.
- Homo sapiens.—Cosmopolitan."
After the classification of the Vertebrata, a digest is given of their geographical distribution. Then follows an approximate number of recent species of vertebrates, giving a total of 24,241 species.
There is a concluding and original note which we reproduce.
"Supposing the fauna of the world was reduced to the 250th part of living species, then the Primates would be represented by one species only, and this being of course Man, his available menagerie would consist of scarcely threescore species, half of which would be Teleostean Fishes. The rest would be composed of a dozen and a half of Singing-birds; half a dozen each of Lizards and Snakes; four Rodents; four non-singing Neotropical Passerine Birds; two species each of Woodpeckers, Hummingbirds, and Bats; one or two each of Parrots, Pigeons, Fowls and some other Game-birds, Kingfishers, and Birds of Prey; and one species each of a Shark, Frog, Toad and Tree Frog, Gecko, Ruminant, and Carnivore."
The Trout has followed the Salmon as subject-matter for a new volume in the Fur, Feather, and (now) Fin Series; and although the capture of the fish occupies a large portion of the work, its natural history is not altogether neglected. It is indeed difficult to read any good book on angling without acquiring some knowledge as to the habits of fish; in fact, it is such knowledge that makes a successful angler. To many naturalists, again, the angler's description of Trout "tailing" and "bulging" will prove a most interesting narrative. "Tailing is a performance frequently witnessed in Hertfordshire and Buckinghamshire waters, and in South-county streams generally. As may be surmised, the phrase 'tailing Trout' means that the fish are plunging their heads into the weeds, or poking about on the bottom of the river, seeking their food amongst the freshwater shrimps, grubs, and similar appetizing morsels; and in comparatively shallow streams this downward operation causes the fishes' tails to appear above the surface of the water." "Bulging" is the explanation of what to the fisherman will sometimes seem "innumerable rises." "On closer inspection these will prove to be fish taking what I believe are called the nymphæ of the Duns or Mayflies just before they reach the surface, there to hatch out."
Col. Custance deals somewhat exhaustively with Troutbreeding. "The three principal breeds of freshwater Trout raised by the British fish-culturist are the English Brook Trout (Salmo fario), the Loch Leven Trout (S. levenensis), and last, but not least, the Rainbow Trout (S. irideus). The first is the one used for general stocking purposes in this country; S. levenensis, although a lake Trout, will also thrive in rivers where there is a considerable depth of water; but Col. Custance gives his vote for the Rainbow Trout, which originally came from America. He describes it as almost satisfying "the Trout-breeder's ideal of perfection." "A splendid surface feeder, he will readily accommodate himself to new water, and will, under favourable conditions, grow with extraordinary rapidity and to a great size."
S. irideus has a common frailty of the Salmonidæ in a propensity to cannibalism, but he is considered to have less of that quality than S. fario, but this is owing to the Rainbow Trout having the smaller mouth.
We may say that the authors of this little volume are anglers among naturalists, and naturalists among anglers.