72 DEEP SEA FISHES. 



The lateral line approximates a parallel with the edge of the back ; it 

 rises somewhat abruptly above the bases of the pectorals, descends similarly 

 at the caudal pedicel, and curves slightly above and behind the erectile 

 spine. 



The colors of a fresh sjDecimen are shown on Plate L', fig. 2. On 

 alcoholic specimens the snout and chin, to a line joining the forehead above 

 the forward part of the eye with a point midway from the lower jaw to the 

 ventral fins, are light flesh color ; behind this the forehead and the nape to 

 the upper part of the orbit are black, and below this black area there is a 

 broad band of silver descending quite across the side obliquely backward to 

 include the base of the pectoral and the vent. Posteriorly from the silver 

 band the body is of a somewhat deeper flesh color. On the tail there is 

 a V-shaped mark of brown with the apex forward at the base of the erectile 

 spine on the side, and behind this mark on the bases of the caudal ra3's 

 there is a narrow transverse band of brown. Most specimens have a narrow 

 edging of brown on the hind margin of the caudal, and a spot of brownish 

 at the base of each ray of the anal fin. 



Total length one and one-sixteenth inches. 



Taken off the Cocos Islands at the surface. 



TRACHTNOIDS. 



In the deep sea portion of the collection there are but two species 

 belonging to this group, and these represent genera of very different habits. 

 One of them is an uranoscopoid from the bottom, and the other a chiasmo- 

 dont, affecting levels at a distance from the floor of the sea. The first of 

 these, Kathdostoma, properly belongs with the shore fishes, but the records 

 show it to have been taken at depths ranging from several to 210 fathoms. 

 The second of them, Chiasmodon, is the genus in the group to which the 

 greatest depth is assigned, 1,500 fathoms, by GUnther, in the " Challenger " 

 report. It was taken by the "Investigator" in 920 fathoms, and by the "Alba- 

 tross " in 919. In the " Three Cruises of the ' Blake,' " A. Agassiz, 1888, IT., 

 p. 29, it is remarked of Chiasmodon niger that " most of the specimens known 

 have been collected at the surface, and there seems to be a reasonable proba- 

 bility that this genus inhabits intermediate depths, since mid-depth fishes 

 only have been found in its stomach." There is nothing in the appearance 

 or the structure of the species described below to indicate that it differs in 



