The ?iatural History of the Frilled Sharh 305 



Shark, presumably because of its reptile'like head and long slender body and tail. Another 

 Japanese name is Kagurazame or Scaffold Shark. This last name we get from Jordan and 

 Fowler (1903). For its significance we can offer no suggestion. 



The facts that Doflein (1906) designates this fish as Schlangenhai and that Mertens 

 (1921) calls it Krausenhai, do not controvert the statement that there are no vernacular 

 names except the Japanese ones known to us, since these terms are merely the German for 

 "snake shark" and "frilled shark" respectively. 



AFFINITIES OF CHLAMTDOSELACHUS 

 WITH EXTINCT SHARKS 



So hot a controversy raged over the supposed relationships of the frilled shark to 

 fossil forms that we think it best to set forth with some care the positions and arguments 

 of those involved in order to show the steps leading to the final conclusion. 



Carman's general remarks on the subject are to the point and make an interesting 

 and valuable introduction to the matters considered in this section. His first description 

 of Chlamydoselachus (1884.1) appeared on January 17, 1884. In this paper he names our 

 shark and places it in the family Chlamydoselachidae. He remarks on its "embryonic 

 look" and says that this calls for a comparison with fossil selachians, among which however 

 he found none "at all near." He then concludes as follows: "However, the type is one 

 which produces the impression that its affinities are to be looked for away back, probably 

 earlier than the Carboniferous, when there was less difference between the sharks and the 

 true fishes." This thought is repeated and emphasizied in his next paper (February 1, 

 1884) where he adds (1884.2): "I am inclined to consider this [shark] the type of a new 

 order, to which the name Selachophichthyoidi might be given, and which stands nearer 

 the true fishes than do the sharks proper." The erroneous idea that Chlamydoselachus 

 "stands nearer the true fishes than do the sharks proper" is possibly based on the presence 

 of such structures as the nearly terminal mouth with the hinges of the jaws at a point 

 behind the skull, and the operculum'like first gill-cover which is continuous across 

 the throat and "free from the isthmus." 



SUPPOSED RELATIONSHIPS WITH CLADODUS, 

 AND WITH DIDTMODUS OR DIPLODUS 



Carman has been quoted to the effect that he could find no fossil representatives of 

 the selachians "at all near" to Chlamydoselachus, although in Cladodus of the Devonian, 

 he found (1884.1, p. 55) "a form with teeth somewhat similar, a median and two lateral 

 cones on each tooth, but the cones are straight instead of curving backward and the 

 enamel is grooved or folded instead of smooth." This was also repeated in Carman's 

 second paper (1884.2, p. 117). Carman cautiously called these teeth "similar" and spoke 

 of their mere "resemblance." 



