VO l889. n '] PROCEEDINGS OF THE NATIONAL MUSEUM. 163 



Mouth small ; maxillary slightly longer thau iu peruanus, reaching pupil, 

 3 in head. Eye shorter than snout, 4£ in head. Teeth small, villiform, 

 outer enlarged, those of upper jaw largest. 



Preoperele with a crenulate membranous border ; least width of pre- 

 orbital 6 in bead. Gill-rakers short and rather thick ; 5+10 present, 

 lower much smaller. 



Scales on snout, below eyes, and on anterior part of breast, cycloid ; 

 caudal scaly; dorsal and anal nearly scaleless, with a scaly sheath at 

 base. 



First dorsal spine very short, inserted over base of pectorals; third 

 and fourth equal, 2£ in head. Anterior dorsal rays 3 in head, posterior 

 2£. Second anal spine 3 in head, longest ray, 2. Distance between 

 bases of ventrals and anal, 3 in body. Pectorals not extending beyond 

 ventrals, 1§ to Iff in head. Ventrals not reaching vent, 1^ to If in head, 

 outer ray filamentous. Longest caudal ray 1| in head, fin shaped as 

 in peruanus, the median rays longest, the upper lobe slightly truncate 

 and slightly coucave, the lower cut off still more obliquely. 



Color bluish-silvery, more yellow beneath ; scales from base of pecto- 

 rals to caudal with larger dots. Back with four or five very faint broad 

 dusky cross-bauds, the one at end of spinous dorsal largest ; a black 

 spot larger than eye near origin of lateral line. Membrane of spinous 

 dorsal thickly dusted ; soft dorsal with a pale streak through its middle. 

 Anal, outer half of ventrals, and nearly all of pectorals dusky ; caudal 

 rusty at base, followed by a pale area and then a dusky one. 



Several specimens of this species were obtained by the Albatross 

 at Panama. It is named for Mr. Richard Rathbun of the U. S. Fish 

 Commission. 



17. Kathetostoma averruncus sp. nov. 



Diagnosis. — Allied to the Australian species Kathetostoma leave, dif- 

 fering in the smaller number of dorsal rays and perhaps in coloration. 



Type: ISo. — — , U. S. National Museum. 



Hab.— Pacific Ocean, off coast of Columbia; 8© 57' K, 79° 31' 30" W. 

 (Station 2800). 



Description- Head, 2| (3£); depth, 3f (44). D. 13; A. 13. Length 

 of type, 4£ inches. 



Body short and robust, its width behind base of pectorals equal to 

 length of top of head. Head very large, its width at preoperele less 

 thau its length by half length of eye. Mouth large, vertical; maxil- 

 lary 2 in head. Snout If iu eye. Eye rather small, 5 in head. Teeth 

 of lower jaw largest, inner row of both jaws enlarged aud movable. 

 Lower jaw without tentacle. Interorbital space slightly concave, U 

 times length of eye. Premaxillary groove as broad as long, 1£ in eye; 

 obtuse behind, extending backward just past middle of pupil. Distance 

 between bases of humeral spines 1J in top of head. Preorbital with 

 three spines iu front directed forward and downward. Preoperele with 

 three spines below angle directed downward and forward, Two antrorse 



