298 Bashford Dean Memorial Volume 



PARASITES OF THE FRILLED SHARK 



Two investigators have found parasites in Chlamydoselachus. Within the cardiac 

 chamber of his first specimen, Garman (1885.2, p. 19) found, figured, and described a 

 parasitic worm attached to the lower side of the auricle. This parasite was identified by 

 Dr. E. L. Mark as an undescribed species of Tetrarhynchus. The specific name wardii 

 was given to it in honor of Mr. H. A. Ward, who procured the fish in Japan. 



CoUett (1897.1, p. 15) writes thus of parasites in his huge fish: "The stomach was 

 empty and did not contain any parasites. Amongst the spiral valves, on the other hand, 

 there were hundreds of a small Cestoid; it was, besides, occupied by a single short and 

 thick Trematoid." These cestodes belonged to the genus Monorygma, but they formed 

 a new species to which the name M. chlamydoselachi was given by Dr. Einar Lonnberg 

 (1897). The trematode was not positively identified but was thought to be Distomum 

 veliporum. 



In our fish No. I, we found in the cardiac region of the stomach three roundworms 

 ranging in length from about 3 to 6 in., and in the small intestine (the bursa entiana) five 

 roundworms varying from 2.5 to 5 in. long. It was clear that they belonged to the group 

 Nematoda, but for further identification they were submitted to Prof. H. W. Stunkard 

 of New York University who reports on them as follows : 



I have been able to clear the nematodes from the intestine of Chlamydoselachus, and find 

 that they are all females. The largest ones are sexually mature, and the smaller ones are still 

 immature. They obviously belong to the family Ascaridae, but since no males are present it is 

 not possible with certainty to make more detailed identification. 



BREEDING HABITS OF CHLAMYDOSELACHUS 



Elsewhere note has been made of the myxopterygia or claspers which are modifica' 

 tions of portions of the pelvic fins in the male. These copulatory organs, though struc- 

 turally very primitive in Chlamydoselachus (see Figure 17, plate V), indicate that fertiliza- 

 tion is internal. This, however, gives no clue to the particular method of reproduction, 

 since in all known sharks, egg-layers and viviparous forms aHke, impregnation is internal. 

 Although in many of its structures Chlamydoselachus is one of the most primitive of the 

 existing sharks, in its breeding habits it is among the most specialized. 



VIVIPAROUS MODE OF REPRODUCTION 



Chlamydoselachus is viviparous. This was presumably recognized by its discoverer, 

 Doderlein, in 1881, as we learn from Rose (1895) whose 340'mm. (13.4-in.) embryo came 

 from the body (Letbe) of one of Doderlein's specimens. The structure of the reproductive 

 organs will be dealt with in a later article; here we are interested in them only in that they 

 protect and bring forth living young. 



Garman's original specimen was partially eviscerated, and in his preliminary paper 

 (1884.1) he does not refer to the reproductive organs. However, in his monograph (1885.2) 



