182 RECORDS OF THE AUSTRALIAN MUSEUM. 



and from the examination of several actual specimens, I believe 

 the separation will hold good. It is also necessary to make the 

 same remark on Dana's figure; he certainly describes S. costata 

 plainly enough, but his illustration represents the form or con- 

 dition known as .S'. compressa without a doubt. 



The characters of S. compressa are practically those of S. costata, 

 with the following exceptions : — The shell is rather more com- 

 pressed, ligamentary pits of the hinge larger, anterior adductor 

 scars subdivided by a groove, posterior adductor scars much 

 transversely elongated, and an entire absence of the radiating 

 posterior costpe. The general characters are so much alike in the 

 two, that I shall look forward with much curiosity to future 

 descriptions of these shells. 



Loc. and Hor. — Jamberoo, and Black Head, lUawarra District 

 — Upper Marine Series. 



Stutchburia simplex, Dana, sp. 

 Modiolopsis shnplex, Dana, Am. Journ. Sci., iv., 1847, p. 159. 

 Cypricardia simplex, Dana, Wilkes' U. S. Explor. Exped., x., 

 1849, p. 703, pi. 9, f. 2. 



Obs. — Four shells in our collection correspond in outline and 

 size with the above species of Dana's, but with the internal 

 characters agreeing in every respect with those of Stutchburia, as 

 for instance those of the hinge, adductor impressions, and palial 

 lines. The only points of departure are the size, a more truly 

 oblong shape, and the exterior simple, sub-plicate, and not at all 

 radiate. In the absence of Dana's type, it is, of course, impossible 

 to speak with certainty, but I am strongly of opinion that his 

 species appertains to the present genus. 



Loc. and Hor. — WoUongong, Illawarra District; Jervis Bay, 

 Shoalhaven District. — Upper Marine Series. 



Stutchburia farleyensis, sp. nov. 

 (Pi. xxxii., figs. 3-6.) 



Sp. Char. — Shell transversely elongated, oblong to almost 

 quadrangular, moderately compressed, average Irngth one and three 

 quarter inches, breadth one inch ; dorsal and ventral margins 

 sub-parallel, the former straight, and not quite as long as the vales, 

 the latter slightly insinuated near the middle, and expanding 

 posteriorly; anterior ends very small, margins slightly oblique from 

 the urabones downwards, but in some examples almost straight 

 walled ; posterior ends much compressed, margins well and gently 

 rounded ; valves most convex about widway between the umbones 

 and posterior termination of the hinge lines; posterior ridges very 

 obtuse, dying out on the compressed posterior ends, above and 



