340 PECTUNCULTJS. 



Pectunculus cainozoicus, Teni son- Woods (sp.). 



1877. Cucullma cainozoica, Teuison-Woods, Pap. Eoy. Soc. Tas. 1876, p. 111. 

 1886. Pectunculus cainozoicus, Tate, Trans. Roy. Soc. South Aust. vol. viii. 



p. 136, pi. X. figs. 9,a-b. 

 1888. Pectunculus cainozoicus, Johnston, Geol. Tasmania, pi. xxxi. figs. IZa-b. 

 1893. Pectunculus cainozoicus, Tate and Dennant, id. vol. xvii. pt. 1, p. 224. 

 1896. Pectunculus cainozoicus, Pritchard, Proc. Roy. Soc. Vict. vol. viii. n.s. 



p. 130. 



Shell roundly trigonal, oblique ; surface faintly and closely 

 marked with radiating ribs and concentric striae and ridges ; 

 umbones acute, incurved; area conspicuous, broad, traversed by 

 divergent ligament grooves ; teeth large, oblique ; adductors of 

 the valves large, shell on the inside of each depressed, the edges 

 of the depressions bordering the scars and meeting the simple 

 pallial line. 



It is closely allied to P. cor, Lamarck, and young specimens 

 of that are separated with difficulty from the present species. 

 P. cainozoicus, however, has a relatively larger hinge, the umbones 

 are more elevated and acute, and the depression on either side 

 of the adductor scars is characteristic. 



Dimensions. — Height 51 mm. ; length 52 mm. 



Form, and Log. — Eocene and Miocene : Tasmania and Victoria. 



83981. Two examples of the neanic stage of growth; from 

 Table Cape. Purchased. 



L. 4825. Three specimens of the adult ; from Muddy Creek. 



Presented hy John Dennant, Esq^. 



L. 6590. Left valve ; from Muddy Creek. Purchased. 



L. 6616. Pdght valve, abnormally thickened ; from Muddy 



Creek. Purchased. 



L. 9896. Pour examples ; from Table Cape. Purchased. 



Pectunculus subtrigonalis, Tate. 



1886. Pectunculus suhtrigonalis, Tate, Trans. Eoy. Soc. South Aust. vol. viii. 

 p. 137, pi. xi. figs. %a-h. 



Shell solid, subtrigonal, subequilateral, oblique, slightly pro- 

 duced, convex ; surface having about thirty conspicuous, broad, 

 rounded, radiating costse, separated by rather smaller, concave 



