624 SCIENTIFIC RECORD FOR 1884. 



tion to the number of niyocommas as an excellent taxonomic character.'* 

 Dr. Giintber was thus led to recognize six species of BrancMostoma: 

 (1) B. elo/ignfnm, Peru; (2) B. bassamcm, Bass Straits; (3) B. Belcheri, 

 Borneo; (4) B. caribccnm, West Indies; (5) B. lanceolakan, Europe; (6) 

 B. [Epiffonichthys] ciilteUus. The B. hassanum was new. {Rep. Zool. Coll. 

 Alert, itp. 3l-3o.) 



Selachians. 



An Uel-WxC Shark. — Perhaps the most interesting discovery of the past 

 year among new vertebrate forms is a species of shark made known by 

 Mr. Samuel Garnjan,of Cambridge, under the name of Chlamydoselachus 

 anguineiis. All the ])reviously known sharks are pretty uniform in hav- 

 ing the body of a more or less fusiform contour and comparatively stout; 

 any differences in contraction or elongation are comparatively slight. 

 The new form, however, differs widely from all other described species, 

 and is so elongated as to suggest the snake- or eel-like form, which has 

 struck Mr. Garnjau and induced him to give to it the name anguineus or 

 snake-like. In other respects, it has more characteristics in common 

 with the Notidanids or Hexauchids (that is, the family represented by 

 the gray shark of Europe) than with any other. As in the Notidanids, 

 there is only one dorsal tin, and in the new shark this is reduced in size 

 and far behind, opposite the anal; the latter is much larger than tlie 

 dorsal and is elongated ; the ventral tins are also behind the middle of the 

 length and reach to the anal. "The head is broad, slightly convex on 

 the crown, and has a look about it," says Mr. Garman, "that reminds 

 one of some of the venomous snakes." The mouth opens at the ante- 

 rior extremity, and is not overhung by the snout, as in most sharks. 

 The gape is very' wide, lateral, and extends far behind the eyes. Tlic 

 nostrils are also unlike those of ordinary sharks in being lateral. As 

 in the Notidanids, the branchial apertures are in increased number (six), 

 but those iu front are very wide, and are quite characteristic in that 

 "the frill or flap covering the first opening is free across the isthmus, 

 as in [some] fishes, and hangs down about an inch." The teeth are also 

 very peculiar. As in other sharks, they are arranged in rows across 

 the jaws. In detail, "they are all alike; each tooth has three slender, 

 curved, inward-directed cusps, and a broad base, which extends back 

 in a pair of points under the next tooth, thereby securing firmness and 

 preventing reversion. In the twenty-eight rows of the upper jaws and 

 twenty-seven of the lower there are three times as many rows of the 

 fangs or cusps." 



Mr. Garman, in considering the relations of this remarkable animal, 

 thought that most resemblance was to be found in the dentition to the 

 teeth of Cladoclus, of the Devonian, "but the cusps were erect instead 

 of reclining, and the enamel was grooved or plicate instead of smooth." 

 He was impressed by a study of the animal "with the idea that, away 

 back iu times wlien selachia and fishes were more alike, he would 



