The Anatomy of Chlamydoselachus 



475 



Concerning the source of his material for study 

 of the cranial anatomy of Chlamydoselachus, Allis 

 (1923, p. 123) wrote as follows: 



In 1902, Professor Bashford Dean, of Columbia 

 University, New York City, most kindly sent me a 

 single head of Chlamydoselachus, and it was given to 

 my assistant, Mr. Jujiro Nomura, for dissection. It 

 was, however, soon found that this one head would 

 not suffice for the work contemplated, and, at my 

 request. Professor Dean had several other heads sent 

 me from Japan. 



In all the figures of the brain of Chlamydosela^ 

 chus, the divisions are very incompletely labeled. 

 To one familiar with the structures of the elasmo- 

 branch brain, the parts are readily recognizable. In 

 any event they may be identified by reference to 

 my Figure 28, plate VII, and to Text'figure 116, 

 after Daniel, representing dorsal and ventral views 

 of the brain of Heptanchus, which is very similar 

 to that of Chlamydoselachus. 



Today, there are available for comparison a 

 wealth of figures of the elasmobranch brain that 

 were not in existence when Garman wrote his 

 description of the brain of Chlamydoselachus. 

 Particular mention should be made of the many 

 fine drawings of selachian brains published, much 

 later, by Garman (1913) himself. These, buried 

 in his great systematic monograph on "The Pla' 

 giostomia," have probably never received the at' 

 tention that they deserve. They do not, how 

 ever, include figures of the brain of Chlamydoseh 

 achus nor of any notidanid. 



THE CRANIAL NERVES 



md.v. 



Text-figure 116. 



The brain and cranial nerves of Heptanchus 



maculatus in ventral view. 



hu.VII, buccal branch of facial nerve; di., dien- 

 cephalon; hmd., hyomandibular division of the facial 

 nerve; il., inferior lobe; med., medulla; ms., mesen- 

 cephalon; md.V, mandibular division of the fifth or 

 trigeminal nerve; mx.V, maxillary division of the 

 trigeminal; os.VII, ophthalmicus superficiahs division 

 of the facial nerve; tl., telencephalon; v.s., vascular 

 sac; w. to z., occipitospinal nerves; 11, III, IV, VI, 

 IX and X, cranial nerves. 

 After Daniel, 1934, Fig. 200b. 



Garman's (1885.2) account of the cranial nerves of Chlamydoselachus is limited to 

 naming them and to describing, in a very general way, the superficial origin of their 

 roots. Hawkes (1906) has given us the only comprehensive and detailed account of the 

 entire series of cranial nerves; her illustrations of these nerves are reproduced herein. 



