II. DEVELOPMENT. 



BREEDING HABITS. 



Chimara colliei, to which the following notes refer unless otherwise stated, 

 spawns at all seasons of the year. The writer has himself collected eggs from June 

 till September. On another occasion he received in June a gathering of eggs which, 

 judging from their stages of development, were deposited during March, April, and 

 May. In April (1898) Dr. Wilbur opened a number of eggs, one of which was 

 evidently deposited in January or late in December. Dr. Wilbur's collecting notes 

 remark further that in December (1898) there was lost a hatching-case containing 

 eggs (about two dozen) collected between September and December. While 

 eggs can thus be secured throughout the year, a season of maximum spawning 

 probably occurs. In Californian waters this appears to be during the late summer 

 and early fall. 



The place of spawning in this species is known in a general way. A naturally 

 deposited egg was taken, as above noted, in water of 65 fathoms on gravelly bottom. 

 There is good evidence that the capsules are attached to rocks or heavy sea-weed, 

 since a definite organ of attachment is present at the filamentous end of the 

 egg-case. It is even possible that the eggs are deposited on favorite spawning- 

 grounds. Thus it was found that in an area of about 2 acres (Discovery Bay, 

 Puget Sound, 200 yards off Tukey's Point, in water of 6 fathoms) as many as 85 

 capsules were dredged in a single day, while in neighboring regions they were only 

 occasionally noticed. 



From the habits of Chimaera it is very doubtful whether its copulation and 

 spawning will ever be observed. By indirect evidence, however, the mode of 

 copulation appears to be distinctly shark-like. The accessory claspers, i. c., the 

 male's frontal spine and anterior appendage of the pelvic fin, are evidently of use in 

 securing the female and retaining her in copulo. 



Garman long ago (1877) suggested that the frontal "holder" functioned in 

 securing the pectoral fin of the female and in "turning her," thus serving like the 

 hooks on the pectoral fins of the male ray; and he further maintained that the pelvic 

 claspers were used for holding the mixipterygia when erected. As far as the frontal 

 spine is concerned, a more probable interpretation is that the male Chimaera (cf. 

 the position in shark) wraps its body about the female and secures final attachment 

 in copula by attaching the spine near the female's dorsal fin ; for it was found, in an 

 examination of specimens which were about to deposit eggs, that well-marked scars 

 were present, indicating the point of attachment. The region of the dorsal fin in such 

 examples is shown in figs. 7 to 1 1 ; and there can be no question, from a closer 

 examination of the scars, each of which is shown enlarged on the same page 



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