578 PROCEEDiyCrfi of the national museum. vol. XXXVI. 



fins is equal to the distance from tip of snout to caudal edge of these 

 fins. The lax skin makes it difficult to see the true shape of the ven- 

 tral fins. They appear to be less developed than in other members 

 of the family. They are adnate to the tail their entire length and 

 have the rays rather feebly developed. Two dorsal fins are developed, 

 the second much larger than the first, the first dorsal inserted 

 slightly in advance of the caudal edge of the ventrals; caudal large, 

 obovate, with the dorsal edge nearly straight and the ventral edge 

 obliquely rounded; tail with a very distinct lateral fold; eyes want- 

 ing or rudimentary, their position indicated by a pale spot situated 

 1| cm. in front of the spiracles; teeth flat or concave, broadly 

 rhombic with a small backward projecting point and arranged in 

 quincunx; spiracles large, the edges not fringed or tuberculate; nasal 

 valves confluent into quadrangular flap; a large electric organ devel- 

 oped between the head and pectoral fin on each side. 



The skin over the entire body is very lax and flabby, making it 

 difficult to see the true shape of the creature and take its measurements. 

 The species is known from a single specimen, a female 49 cm. long, 

 taken at station 2GG0 b}^ the steamer Albatross of the Bureau of 

 Fis^heries, May 3. 1880, at a depth of 504 fathoms, in the course of 

 an exploration of the eastern coast of the United States. 



Measuremen ts. '^'"'• 



Total length (lOi'i; in.)-- 49.0 



Total length, without caudal 40.5 



Tip of snout to end of ventrals -. 28. S 



Tip of snout to end of pectorals 21. G 



Tip of snout to origin of first dorsal 28. .5 



Tip of snout to origin of second dorsal 32.6 



Tip of snout to spiracles 0. S 



Tip of snout to nostrils T. 



Tip of snout to first gill slits 12.0 



Tip of snout to last gill slits 16.0 



Tip of snout to mouth S. 7 



Tip of snout to vent 24.5 



Vent to end of caudal 24.5 



Length of first dorsal base 2. 8 



Length of second dorsal base 4.0 



Length of caudal 8.5 



Diagonal height of first dorsal from origin to highest point 4. 5 



Diagonal height of second dorsal 6. 5 



Depth of caudal from highest point to horizontal projection of lowest part- 6. 



Width across pectorals 21.5 



Width across ventrals 14.0 



Width between spiracles 4..'} 



Width between nostrils 3.8 



Width of mouth 2.0 



Width between first gill slits 5.3 



Width between last gill slits 4.4 



Length of opening of each gill slit about ■- 1.0 



