xo. 2075. FISHES FROM SOUTHERN CALIFORNIA— GILBERT. 323 



over middle of orbits, 7; diameter of eye, 5; distance from tip of 

 snout to end of maxillary, 26; to mandibular angle, 27; length of 

 barbel, 61 ; greatest depth at nape, 17; least depth, 3; distance from 

 tip of snout to base of pectorals, 24; to base of ventrals, 58; to 

 origin of dorsal, 78; to origin of anal, 79; length of filamentous pec- 

 toral rays, 18; longest ventral ray, 19; length of base of dorsal, 14. 

 of anal, 17. 



Body deepest at the nape; occiput and interorbital space strongly 

 arched transversely, the eye about equidistant from profile and from 

 mouth; anterior profile strongly decurved from the occiput to the 

 very narrow rounded snout. Nostrils without tubes, in a horizontal 

 line in front of eye. 



Mandible with a strong anterior pair of fangs which in the closed 

 mouth lie in shallow grooves in the anterior surface of the snout and 

 upper jaw. A second somewhat shorter pair also lie outside the 

 premaxillaries, when the mouth is closed, in deeper grooves or sockets 

 beneath the posterior nostrils. Behind this five pairs of shorter 

 canines of about equal length, evenly spaced along the jaw. Teeth 

 in premaxillaries agreeing in number and arrangement with those in 

 the mandible, but all shorter than the shortest of the mandibular 

 series; the posterior premaxillary fangs are retrorse. Maxillary 

 firmly joined to premaxillary, its entire length beset with minute 

 retrorse teeth. Palatine teeth small, in a single series. Eye small, 

 its diameter less than length of snout, its anterior margin in advance 

 of the middle third of the jaw. Barbel very long and slender, reach- 

 ing well beyond base of ventrals, provided with a smooth club- 

 shaped tip. 



Dorsal and anal opposite and nearly equal. Caudal moderately 

 forked. Ventrals inserted low, midway between base of caudal and 

 middle of cheek, the elongate tips nearly reaching the vent. 



Color black. Head, body, and fins thickly beset with minute 

 luminous bodies, many of which are arranged in vertical interseg- 

 mental lines. Two lengthwise series of slightly enlarged spots on 

 lower part of sides, the upper series usually widely spaced, but with 

 occasional groups of four or five closely crowded spots occupying 

 definite positions. The integument has suffered to such an extent 

 that a detailed description of the two series is impossible. A narrow 

 curved luminous organ on the lower margin of the anterior half of 

 the eye and a larger oval spot behind it on the cheek. 



Only the type known. 



IDIACANTHUS ANTROSTOMUS Gilbert. 



One specimen from station 4415, off Santa Barbara Island, depth 

 131 to 638 fathoms. 



