The pectoral fins consist of about 13 short rays. 



The ventral fins have one strong spine 4.5 mm long, and 5 rays. 

 Their base occurs vertically below the first spine of the dorsal fin. 



The dorsal fin consists of 9 spines of the following dimensions: 

 1st — weakest and shortest — 2.1 mm; 2nd — 3.5 mm; 3rd — though 

 broken off at the end was perhaps a little higher or at least as high as 

 the next one; 4th — 4.9 mm; 5th — 8th are gradually reduced, while the 

 9th (last) is slightly longer than the 1st, being 2.6 mm. The length of 

 the 2nd dorsal spine represents 30 percent of the body depth at the 

 beginning of the dorsal fin, while the length of the 4th spine represents 

 43 percent of that depth. The other dorsal fin consists of about 17 

 soft rays whose length could not be determined owing to the bad state 

 of preservation. The interneuralia are unknown here; very faint traces 

 indicate the presence in front of the 1st dorsal spine of one, possibly 

 two, free interneuralia. 



The anal fin begins vertically more or less below the 3rd ray of 

 the 2nd dorsal fin. It consists of three strong spines, respectively 

 1.9 mm, 3.3 and 3.3 mm in length. In addition to these spines in the 

 anal fin, there are also 14 soft rays. Interhaemalia unknown with the 

 exception of the first which is rather long. The whole body is covered 

 by small, well preserved cycloidal scales, with distinct minute striae. 



General reTuarks. The form just described comes closest to genus 

 Equula Cuvier in shape of body and skull, and most particularly be- 

 cause of the presence of a high occipital crest, the occurrence of minute 

 teeth conforming in size, and also in the structure of the anal fin and 

 scales. It differs, however, from many recent species, and from the fossil 

 species Equula altapinna Weiler, in the structure of the lower pre- 

 opercular border as well as in that of the dorsal fin. The most marked 

 difference consists in the lack of a small triangular expansion in the 

 lower posterior corner of the preoperculum, which is characteristic of 

 the genus Equula Cuvier (Hess, Weiler 1955). As regards the structure 

 of the dorsal fin, the Sobniow specimen has 9 spines instead of 8, and 

 the longest of them is not the second but the third. Giinther (1860) 

 states, however, that there are 10 spines in the dorsal fin of Equula 

 longimanus, and that the second of these spines attains only one third 

 of the length of the third. Hence it seems that, in spite of size differ- 

 ences of spines in the dorsal fin as compared with the majority of spe- 

 cies of genus Equula Cuvier, the Sobniow form may reasonably be 

 assigned to this genus. 



In the fossil condition, the genus Equula Cuvier is monotypic, 

 being represented by E. altapinna Weiler from the Middle Oligocene 

 septarian (Septarienton) clays in the vicinity of Basle (Hess, Weiler 1955). 



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