PLATE XXXI. 



Pigs. 1 6. VoLA QTJiNQUECOSTATA, Sow., p. 437 J (see also pi. xxxvii) ; specimens of various 



sizes and with a different number of smaller ribs between the larger ones; 1, 2, 

 and 3 are from Moraviatoor; 4 and 6 (internal-view of the flat valve) ; from 

 Odium, Ooiatoor group, and 5 from Arrialoor, Arrialoor group. 



]?i„s. 7 8. VoLA L2EVIS, Drouet, p. 438 ; 7, internal-view of flat valve ; from south-east of 



OJlum ; 8, from Counum, Ootaioor group. 



Pin-s. 10 11. Pecten [Celamys] asperulinus, Stol., p. 432; in fig. 10 the scabrous strife on the 



large ribs are nearly entirely worn off; the left ear and the umbo was completed 

 after another more perfect specimen ; both are from Kaudoor, Arrialoor group. 



Figs. 12 & 17. Amusium sulcatellum, SloL, p. 436; in fig. 12 the right ear is restored in out- 

 line; fig. 17 represents a very young shell; Arrialoor, Arrialoor group. 



Fi^s. 13 & 14. Pecten Verdachei.lensis, Forles, p. 432; left and right valves, (comp. figs. 7 



and 8 on pi. xlii) ; Ootatoor, Ooiatoor group. 



Figs. 15 — 1(3. Pecten [Camptonectes] cdrvatus, Geinitz, p. 433; right and left valves; in 

 the former the radiating strife are finer than in the latter, (comp. figs. 4 — 6 on 

 pi. xli) ; Arrialoor, Arrialoor group. 



pjfj-s. 18 — 19. Pecten Akcotensis, 5/y^., p. 432 ; Striper matur, Arrialoor group. 



Figs. 20 — 21. Pecten kaduloides, Stol., p. 431 ; the valves of the specimen are slightly shifted j 

 south-west of Mulloor, Arrialoor group. 



