18 DEEP-SEA FISHES OF THE ATLANTIC BASIN. 



the eye; gill openings moderate, in advance of the i)ectoral; jaws armed with numerous 

 rows of small, tricuspid teeth; first dorsal fin opposite the space between pectorals and 

 ventrals, long and low, gradually increasing in height posteriorly ; second dorsal behind ven- 

 trals, opposite and similar to anal; ventrals and pectorals well developed; no pit at the root 

 of caudal fin, the basal lobe of which is very low and hmg; skin with minute asperities. 



PSEUDOTKIACIS MICRODON, Capello. (Figure 18.) 



Paeudotriaeis microdon, Capello, .Jdfu. Sc. Math. Phys. e Nat. Lisb., iv, pi. 5, fij;. i; Joni. Acad. Sc. Lisboa, 

 I, 315, 321, pi. v; loc. cit., ii, 139; Cat. Peix. Port., 1880, 44.— Gunther, Cat., viii, 395.— Bean, Proc. U. 

 S. Nat. Mas., 1883, 147. 



The following d'escriptioa and table of measurements are from Dr. Bean's account of 

 the species: 



The greatest height of the body is at the origin of the first dorsal ; it is contained eight 

 and three-sevenths times in the total length. The height at tlie origin of ventrals is con- 

 tained nine and oue-half times in total length. The height ot head at the first gill opeiiiug 

 is a little greater than that of body at the ventral origin, while the height of the head at 

 the angle of the mouth is a little less than one-eleventh of the total length. The least 

 height of the tail equals the height of the aual, and is contained twenty-five times in total 

 length. 



The head is somewhat depressed in front, with moderately sharp snout, which is nearly 

 twice as long as the distance of its tip from the mouth. Tbe distance from snout to last 

 gill opening is contained five times in total length. The distance from snout to first gill 

 opening, mea.sured horizontally, equals twice the heiglit of body at origin of second dorsal. 

 The distance between the first and last gill openings e(|uals nearly twice the length of the 

 eye. The height of the first gill opening is about ecpial to the di.stance between the angle 

 of the mouth and the spiracle. The height of the head at angle of mouth is contained 

 eleven times and at the first gill opening nine times in total length. The length of the 

 snout equals oue-half the body height at origin of first dorsal. The distance of mouth 

 from snout, measured on the axis of the fish, equals one-third width of mouth. The dis- 

 tance from snout to angle of mouth, obliquely taken, equals one-fourth the distance from 

 snout to last gill opening. The distance between eye and spiracle equals that from juouth 

 to nostril. The distance from angle of mouth to spiracle is about equal to height of first 

 gill opening. The spiracle is moderately large, the length of its opening being contained 

 twice in the height of fourth gill opening. The oblong eye is placed near the dorsal })rofile; 

 the length of the orbit is about one-half the greatest height of second dorsal; the length of 

 the eye equals about one-fourth width of mouth. The length of upper jaw is slightly more 

 than that of lower, and nearly equals the distance between the spiracles. The distance 

 from the mouth to the nostril is about one-fourth least height of tail; the distance between 

 nostrils equals four times the distance from eye to spiracle. The interorbital space equals 

 one-half the length of second dorsal base. The distance between the spiracles equals four 

 times their greatest length. 



The first dorsal is very long and low, highest behind its middle, the length of its base 

 equal to seven times its greatest height; its distance from the snout is a little more than 

 twice the greatest length of pectoral. The second dorsal is distant fi-om the end of the first 

 a length equal to nearly twice its greatest height; the length of its base is somewhat more 

 than the body height at origin of first dorsal. 



The second dorsal begins at a distance from the end of the first, equal to the height of 

 body at ventral origin; the length of its base e(|uals twice the interorbital distance; its 

 height equals nearly twice the length of the orbit. 



The anal is entirely under the second dorsal, but its base is a little less than five-sev- 

 enths as long as that of the latter; the greatest height of the ,.nal equals the least height 

 of caudal i)eduncle. 



