. A manual of elementary zoology . Zoology. COLD-BLOODED VERTEBRATA 381 o armour plates, over which the epidermis wears away, very different from the thin rounded cycloid scales which clothe the majority of Teleostomi. It is on some of these ganoid scales that vestiges of the spine occasionally remain. All these features, however, disappear in the great mass of ordinary bony fishes or Teleostei. The The Cocl' : Whiting (Gadus merlangus), which, with its near kindred the Haddock (G. ceglefinus) and Cod (G. morrhua), is often dissected in the laboratory,1 is a. Fig. 273.—A diagram of the Haddock
. A manual of elementary zoology . Zoology. COLD-BLOODED VERTEBRATA 381 o armour plates, over which the epidermis wears away, very different from the thin rounded cycloid scales which clothe the majority of Teleostomi. It is on some of these ganoid scales that vestiges of the spine occasionally remain. All these features, however, disappear in the great mass of ordinary bony fishes or Teleostei. The The Cocl' : Whiting (Gadus merlangus), which, with its near kindred the Haddock (G. ceglefinus) and Cod (G. morrhua), is often dissected in the laboratory,1 is a. Fig. 273.—A diagram of the Haddock.—From Thomson. Anus; at/1., af^., anal fins; &, barbule; , branchiostegal membrane (a continuation of the gill cover); cf., caudal fin; df.^-d/'K, dorsal fins; g-., genital opening ; na., nasal openings (double on each side) ; o/>., operculum or gill cover; J>f., pectoral fin ; pvf., pelvic fin ; «., urinary opening. typical Teleostean, both in the above respects and in the very large number of bones which compose its complicated skeleton (Figs. 41 r, 412). In it, as in many others, the pelvic fins have shifted forwards till they lie actually in front of the pectorals, and the air-bladder does not com- municate with the gullet. The Salmon, Herring, Carp, and Eel resemble the ganoids in carrying their pelvic fins in the normal position, and in that the air-bladder com- municates with the gullet, which it does on the dorsal side. 1 The student who wishes to study systematically one of these three fishes will find on p. 574 a summary of its anatomy with additional Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Borradaile, L. A. (Lancelot Alexander), 1872-1945. London : H. Frowde, Hodder & Stoughton
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectzoology, bookyear1920
