ATOPICTHYES. 325 



the base of the pectoral below its middle. Vent hardly one fourth of the 

 ocular length backward of the base of the pectoral. 



Dorsal low, originating one half of the orbital diameter behind the 

 occiput, shorter rays backward and degenerating into a series of small, 

 backward-curved, sharp pointed spines. These spines appear near the 

 hundredth ray of the fin and continue for about a hundred rays farther 

 back, where the character again approaches that of the ordinary fin rays. 

 Anal much deeper than the dorsal, first ray below the seventeenth dorsal 

 ray, posterior rays not modified like those in the dorsal fin. Pectorals 

 narrow, little more than twice the orbital length. 



Lateral line with three series of small pores the upper and the lower of 

 which open through short tubes while the median opens directly from the 

 canal. In reality the pores are grouped in fours, as was figured by Brandt 

 in 1850, the groups being separated by single pores of the median series. 

 This grouping is a characteristic of the genus. 



Blackish with reddish tint over the muscular portions, probably black in 

 life. On the specimen from the greater depth the dark color when under 

 the lens is more diffused and does not appear as distinct pimcticulations, as 

 is the case on the specimen described above from a thousand fathoms and 

 more nearer the surface. 



Temperature. Bottom. 



42° F. Gn. S. 



36.4° F. Br. M. bk. Sp. 



ATOPICHTHYES. 



Heretofore certain pelagic, much compressed, band-like, translucent to 

 transparent, larval fishes have been placed in the genus Leptocephalus of 

 Gronow, 1763. The type of the genus is Leptocc2)halns Morrisii Penn., 1776, 

 a larval form which has lately been traced to its adult in Murcena conger 

 Linn., 1758, which, again, was the typical species of Risso's genus Conger, 

 1826. In consequence Leptocephalus has taken the place of Conger as the 

 title of the genus and many of the Leptocephalids which do not belong to that 

 genus and cannot yet be definitely, located are left unnamed. That there is 

 a considerable number of these larval forms that cannot be placed in Lepto- 

 cephalus, but tliat belong to various other genera not now determined with 

 sufficient accuracy is evident enough from the figures and descriptions given 



