470 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 50. 



Head skeleton cavernous, broad, interorbital space one and two- 

 thirds times eye diameter; snout longer than eye, not overhanging 

 mouth; postorbital part of head half its whole length; maxillary end- 

 ing under posterior fourth of eye; lower jaw but slightly, if any, 

 shorter than upper; barbel represented by a very minute papilla at 

 symphysis of lower jaw,, not visible without lens; teeth minute, in 

 narrow bands, about four series wide anteriorly in both jaws, but 

 narrowing rapidly in lower jaw; a very small circular patch of fine 

 teeth on vomer; gill rakers nearly as long as diameter of eye. 



Greatest depth of body at dorsal insertion, which is above point of 

 opercle and slightly before pectoral bases; caudal peduncle depth a 

 third of eye diameter; body profiles nearly straight from tail to deep- 

 est part at dorsal insertion; anus twice as far from ventral bases as 

 from first anal ray; second ray of first dorsal greatly elongated, 

 reaching nineteenth ray of second dorsal; ventrals inserted under 

 posterior hmb of opercle and midway between anus and posterior end 

 of maxillary; second ventral ray reaching eighth of anal, with two or 

 three rudimentary inner rays; first ray broken, apparently not as long; 

 pectoral rays broken, probably equal to length of postorbital part of 

 head; caudal rays broken; contours of dorsal and anal not evident, 

 probably low midway of their length. 



Scales all lost, but traces showing over whole body save gular 

 region; lateral line not evident. 



Coloration lacldng or faded, peritoneum and fining of mouth black. 



This species forms one extreme of the genus, with its next relative, 

 probably Laemonema latifrons Holt and Byrne, ^ from the southwest 

 coast of Ireland. From tliis it differs in the greater number of fin 

 rays, longer filaments of dorsal and anal, vnder interorbital, longer 

 maxillary, and in other ways. It is probable that all species of 

 Laemonema have several rays in the ventrals instead of two, or the 

 "bifid" ray of authors generally. The presence of these small rays 

 has been corroborated by the writer in the present form, L. melanu- 

 rum and L. harbatulum. The barbel is nearly invisible, even more 

 rudimentary than in L. latifrons. 



The long dehcate filaments of the dorsal and ventral rays, broken 

 when the specimens were received, have since worked loose in hand- 

 ling the bottles and have been lost, hence are not evident in the type. 

 They are shown in the accompanying plate. 



The following are the measurements of the type in hundredths of 

 the total length and in tenths of the head, 145 and 32 mm., respec- 

 tively : 



1 Ann. Mag. Nat. Hist., sor, 8, No. 1, 1908, p. 87. 



