ALEPOCEPHALIDAE 267 



SYSTEMATIC ACCOUNT 



Order ISOSPONDYLI 

 Family ALEPOCEPHALIDAE 



The fifteen genera of this family may be conveniently grouped as follows : 



I. Origin of pelvic fins at or about the middle of the length (without caudal) ; eyes normal ; pectoral 

 fins comparatively short. 



A. Snout short or of moderate length. 



1 . Body with scales. 



a. Pelvic fins present. 



* Maxillaries toothless. Alepocephalus (incl. Conocara), Asquawiceps, Ericara, 



Leptochilichthys, Xenognathus 

 ** Maxillaries with teeth. Bajacalifornia, Bathytroctes (incl. Talismania), 



Narcetes 



b. Pelvic fins absent. Platytroctes 



2. Scales absent, sometimes replaced by small nodules. 



a. Maxillary not extending beyond eye ; no fold in front of dorsal fin. 



* Dorsal and anal fins sub-equal, well separated from caudal, which is well developed ; 

 eyes of moderate size. Xenodermiclithys, Rouleina 



** Dorsal fin much shorter than anal, which is more than half the length of fish; 

 caudal peduncle and caudal fin very small ; eyes very large. Leptoderma 



b. Maxillary extending well beyond eye ; a high median fold in front of the dorsal fin. 



Anomalopterus 



B. Snout long, tube-like, with a small mouth at its extremity ; scales minute, scarcely imbricated. 



A ulastomatomorpha 



II. Origin of pelvic fins well behind the middle of the length ; eyes telescopic ; pectoral fins very long. 



Dolichopteryx 



Aleposotmis, Gill, is a synonym of Xenodermiclithys ; MitcliiUina, Jordan and Evermann, 

 and Benthosphyraena, Cockerell, appear to be identical with Alepocephalus. 



Asquamiceps velaris, Zugmayer. 



Zugmayer, 191 1, Bull. Inst. Ocean. Monaco, 193, p. 2; 191 1, Res. Camp. Sci. Monaco, xxxv, 

 p. 10, pi. i, fig. 4. 



St. loi. 14-15. X. 26. 33° 50' to 34° 13' S, 16° 04' to 15° 49' E. 4o m. net, horizontal, 25S0 m. : 

 I specimen, 90 mm.'^ 



Depth of body 5 in the length, length of head 2\. Diameter of eye a little less than 

 length of snout, which is 4-3 in that of head; interorbital width 8A. Maxillary nearly 

 reaching middle of eye; no teeth in upper jaw; lower jaw with microscopical teeth. 

 Gill-membranes united as far back as a point well behind the eye; apparently 5 branchi- 

 ostegal rays; membranous expansion of operculum partly covering the pectoral fin. 

 Scales cycloid, irregularly arranged and partially embedded in the skin; about 65 scales 



^ All the specimens included in this report are measured to the base of the caudal fin. 



