be seen on specimen 124. Os., with some probability identifiable as the 

 interoperculum. The above pattern of the gill covers suggests some 

 resemblance to the living genus Sternoptyx Harm., which also has 

 a long narrow preoperculum and interoperculum (Gregory, 1933, 1957). 



The vertebral column consists of 31 — 33 vertebrae; of the 26 complete 

 specimens available, one half has 32 vertebrae, ten individuals have 

 31 and but three have 33 vertebrae. As a rule, there are 19 — 20 caudals. 

 In the precaudal part, they are nearly as deep as they are long, while 

 in the caudal area their length slightly exceeds the depth. An exception 

 here are the last and the penultimate vertebrae (from the end) which 

 are distinctly shorter. The vertebral column terminates in an upraised 

 urostyle. The hypurals are not very distinctly preserved, but it may be 

 reasonably supposed that the rays on the lower lobe of the caudal fin 

 are supported by at least one, very broad hypural, while in the upper 

 lobe this support is provided by several smaller hypurals. The neura- 

 pophyses and hemapophyses are long and narrow. The presence of long, 

 thin intermuscular bones is confined to the precaudal portion of the 

 vertebral column, both dorsally and ventrally (Fig. 6|); moreover, on 

 some of the specimens they cannot be seen at all. 



The ribs, which are long and thin, reach almost to the ventral 

 margin; there are 8 — 9 pairs of them. The last^pair always belongs to the 

 22nd or 23rd vertebra (from the back). The first two pairs of the ribs, 

 placed immediately behind the head, are always the shortest. 



The pectoral fins are situated low down, immediately behind the 

 head. Owing to the state of preservation, the exact number of rays 

 cannot be determined; the probable figure is 10, 



A large coracoideum, satisfactorily preserved on all specimens, 

 is the best developed element of the shoulder girdle (Fig. 5), while the 

 scapula cannot be discerned. Of the dermal bones the cleithrum has 

 a somewhat characteristic shape, but only its upper, arcuately bent 

 part has been preserved on many specimens. On some specimens, in 

 the proximity of the keratohyale and the preoperculum, there is an 

 expanded bone, terminating in a long spine (Fig. 5); by analogy with 

 the structure of the cleithrum in the living genus Argyropelecus 

 (Gregory 1933, 1957), the present writer supposes that it is the fore 

 part of the cleithrum. 



The ventral fins are short, about 2.0 — 2.5 mm in length, with the 

 exception of those on the largest specimen (No. 157. Os.) which are 

 3.4 mm long. They probably consisted of 7 — 8 rays and were vertically 

 arranged below the 21st — 23rd vertebrae (from the back), close below 

 or in front of the first rays of the dorsal fin (Fig. 6). The pelvic bones 

 are delicate, satisfactorily preserved in the largest individual (157. Os.). 



16 



