. Chimæroid fishes and their development. Fishes; Chimaeridae. THE EGG-CAPSULE. 31 CLASSIFICATION OF \ Fig. 14. from -capsule o( fossil Chimeeroid. Ischyodus t Aletodus), ;er beds (Jurassic), Germany. After Jaekel. Actual From the materials provided in the present table and figures the egg-capsules of Chimaeroids may be classified on some- what the following basis : Callorhynchus. (Fig. 15 a-f.) Capsules with case spindle-shaped; snout-sheath subequal in length to the tail-sheath; lateral web broad, exhibiting stout rugre; of these a conspicu- ous pair proceeds outward from hinge of
. Chimæroid fishes and their development. Fishes; Chimaeridae. THE EGG-CAPSULE. 31 CLASSIFICATION OF \ Fig. 14. from -capsule o( fossil Chimeeroid. Ischyodus t Aletodus), ;er beds (Jurassic), Germany. After Jaekel. Actual From the materials provided in the present table and figures the egg-capsules of Chimaeroids may be classified on some- what the following basis : Callorhynchus. (Fig. 15 a-f.) Capsules with case spindle-shaped; snout-sheath subequal in length to the tail-sheath; lateral web broad, exhibiting stout rugre; of these a conspicu- ous pair proceeds outward from hinge of opercular valve. No serrul» present, the opercular ridges merely separating to admit water, as in related structures in sharks. No caudal pores; in their place a slit on each side of tail-sheath opening on the ventral side in the angle between web and case. Anterior lip of operculum transverse, situated on dorsal side at a considerable distance from anterior margin of capsule. No dorsal keel. Heavy cap- sules, leathery and glabrous. No capsules of Callorhjmchus are known to be definitely associated with par- ticular species, although many of the speci- mens preserved in museums are ascribed to "C ; From a stud}' of the capsules of the species of Chimaera, * however, it is clear that the differences between the capsules described are such that we can not believe that they belonged to the same species. Thus the Chilean capsule (fig. 15), described by Jaekel as "'Cal. autaniiciis" (a synonym of C. cal- lorhynchus of Valenciennes) is probably of a different species from the similar egg- case (fig. 15 a) figured by Dumeril, and this in turn is notably different from sev- eral specimens in the zoological museum of the Jardin des Plantes, which the writer was recently permitted to examine through the courtesy of Professor Vaillant. The latter capsules are accordingly figured ?Variation of the capsules within the range of the species was studied by the
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectfishes, bookyear1906
