is not detectable. Above the cleithrum lies the long, narrow supraclei- 

 thrum which, in turn, joins with the bifurcating posttemporale. 



The vertebral column consists of a varying number of vertebrae 

 ranging in the particular species from 28 to 32. These rather few ver- 

 tebrae seem very characteristic of the genus Eomyctophum Danil., since 

 other fossil genera of the Myctophidae are known to be characterized 

 by considerably more numerous vertebrae. For example, most of the 

 Miocene species from the genera Myctophum and Lampanyctus have 

 over 35 vertebrae (Arambourg, 1925, 1927), (David 1943). The length 

 of the vertebrae, both caudal and precaudal, exceeds their depth. The 

 ribs are long, with the ends nearly reaching to the ventral margin of the 

 body. The first pair of ribs is much shorter than the subsequent ones 

 (Fig. 9). The vertebral column terminates in an upraised urostyle. The 

 exact number and shape of the hypurals cannot be stated owing to the 

 bad state of preservation. 



Delicate, paired intermuscular bones, placed at an acute angle to 

 the bodies of the vertebrae, are observable along the whole dorsal 

 length of the backspine. On the ventral side, these bones are seen only 

 in the caudal part of the body. In addition to these, poorly developed 

 intermuscular bones, subparallel to the bodies of the vertebrae (Fig. 9) 

 may be seen on either side of the vertebral column within the caudal 

 area. 



The pectoral fins are rather short (but their length is subject to 

 specific variability), consisting of 12 — 15 fine rays; only seldom can 

 their exact number be determined. 



The ventral fins consist of 8 thick rays, not always readily discern- 

 ible. Their position varies specifically. The length of these fins could 

 perhaps be regarded as of a systematic character, but owing to the 

 bad state of preservation of the majority of remains here investigated 

 their actual length can hardly be determined. Judging, however, from 

 the best preserved specimens, we may suppose that they did not attain 

 the beginning of the anal fin. 



The dorsal fin beigins always just a little before the mid-body. 

 It consists of 11 — 12 rays, relatively thick and in length as follows: first 

 and last ray almost equal, the second ray is the longest, while the subse- 

 quent ones are gradually reduced (Fig. 9). All the rays, the first one 

 excepted, have bifurcating ends. The interneuralia which support the 

 rays are thin; the 3 first rays are longer and more obliquely placed in 

 relation to the dorsal margin of the body. In all the representatives of 

 the genus Eomyctophum Danil., regardless of species, two free inter- 

 neuralia have been noted before the beginning of the dorsal fin. The 

 last ray of this fin is not supported by a corresponding interneuralium. 



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