40.0 



67.9 



9.0 



12.8 



11.8 



21.3 



8.0 



14.2 



7.4 



12.7 



Dimensions of two, most completely preserved specimens (in mm) 



No. 159. Os. No. 161. Os. 



Body-length without caudal fin 



Greatest depth of body 



Length of the head to posterior margin of 



operculum 

 Depth of the head 

 Length of caudal fin 



Description. The greatest depth of body fits 4.4 — 5.3 times into the 

 body-length without the caudal fin. All the specimens are arcuately 

 curved, the head and forebody turned upwards. The length of the head 

 fits about 3.3 times into the body-length without the caudal fin. The 

 quadrato-mandibular articulation below the anterior margin of the 

 orbit. 



The vertebral column consists of about 43 vertebrae, including 13 

 caudal (counting from the end to the 1st inter haemale). The ribs begin 

 from the 17th vertebra (from the back). Dorsally, there are all along 

 the vertebral column thin but rather long intermuscular bones ^. 



The pectoral fins consisting of 13^14 rays occur immediately 

 behind the head. 



The ventral fins are situated 4 — 5 vertebrae after the 1st ray 

 of the dorsal fin, below the 23rd — 25th vertebra (from the back). They 

 ■ consist of about 8 rays. 



The dorsal fin begins above the 27th — 29th vertebra (counting 

 from the back). Its base has the length of 7 precaudal vertebrae. There 

 are 15 — 17 rays. 



The anal fin is on the whole unsatisfactorily preserved. On speci- 

 men 159. Os 17 rays may be seen; the first of them below the 12th 

 vertebra, the last below the 3rd vertebra (from the back). 



The caudal fin deeply noteched, with 9 cardinal and 6 side rays. 



The scales are partly preserved. Even the keel scales are seen on 

 specimen 117. Os. 



In addition to specimens of Clupea sardinites Heck., detached 

 scales of the genus Clupea sp. are encountered which may have belonged 

 to individuals of C. sardinites Heck. 



The scarcity of C. sardinites Heck, within the Jaslo shales is a very 



2 French aretes musculaires, German Muskel-Graten. 



