1898-1902. No. 32.] FOSSIL FAUNAS FROM SERIES B. 37 



the pleura standing nearly vertical. This form corresponds with that of 

 the head, the lateral part of which also was strongly curved down- 

 wards. The axis is moderately convex, widt a width from 9 mm. in the 

 middle part, 6 7 on the last thoracic segment The pleura show a rather 

 flat and broad surface. 



The pygidium is relatively broad with the two margins, when viewed 

 from above, meeting as nearly straight lines at slightly obtuse angles 

 The axis strongly tapers, has 9 distinctly visible segments, the anterior 

 ones of which curve slightly, the posterior stronger, and more angu- 

 larly forwards. The transverse furrows are deepest near the margins of the 

 axis. On the sides can be seen about 9 pleural lobes, the posterior ones 

 directed strongly backwards and downwards, and are sub-parallel. The first 

 67 lobes are very well marked, with broad flat surfaces and broad 

 furrows between. It is impossible to decide whether there has been a 

 fine punctation on the surface or whether the same has been quite smooth, 

 as the specimen is somewhat weathered. The broad form of this pygidium. 

 the laterally strongly down-curved and posteriorly subparallel pleural 

 lobes remind one strongly of a Calymmene, and without the head I 

 should probably have determined the fossil as belonging to this genus. 



Occurrence: B, lower part, Reindeer Valley. 



Ostracoda. 



Leperditiidae. 



Leper ditia ROUALT. 



Leperditia symmetrica nov. sp. 



PI. VIII, fig. 15. 



I have before me a great number of right valves of a Leperditia, 

 in a good state of preservation. The size varies considerably, the largest 

 specimen found having a length of 8 mm., and a height of 5 mm. The 

 valve is elongate in form, with a relatively long, straight or slightly 

 downward curved hinge-line. The anterior and posterior margin are 

 very finely and regularly curved, running strikingly symmetrically and 

 converging ventrally in a gentle curve. Where they meet the hinge-line, 

 they run into a small well-rounded process. The convexity of the valve 

 is not very great, greatest point of elevation in the middle, where the 

 valve often rises somewhat abruptly. A faint and narrow marginal 

 flattening can be observed in the larger specimens in the upper half of 

 the anterior and posterior margin. The eye-tuberble is distinct, situated 



