14 RECORDS OF THE AUSTRALIAN MUSEUM. 



Ctenostreon pectiniformis, Schlotheim, sp. 



(Plate iii.) 



Ostracites pectiniformis, Schlotheim, Petrefactenkunde, i., 1820, 

 p. 231. 



Lima prohoscidea, J. Sby., Min. Con, Gt. Brit., iii., 1821, p. 115, 

 pi. cclxiv. 



,, proboscidea, Goldfuss, Petrefacta Germanife, ii., 18.3G, p. 88, 

 pi. ciii, fig. 2. 



,, pectiniformis, Bronn., Index Pal., Noraen., 1848, p. 647. 



,, pectiniformis, Bronn., Lethsea Geognostica, 3rd edit,, ii,, 

 TheiU, 1851, p.214, pi. xix., figs. 9 and 10, lOa and b (for 

 full syno7iomy). 



„ pecti^iiformis, Morris ife Lycett, Moll. Gt. Oolite (Pal, Soc), 

 pt. 2, 1853, p, 26, pi. vi., fig, 9. 



,, proboscidea, Clarke, Quart. Journ. Geol. Soc, xxiii., 1867, 

 p. 8. 



Ctenostreon proboscideum, Eichwald, Letha?a Rossica, ii,, 1., 1868, 

 p. 457. 



Lima proboscidea, Moore, Quart. Journ. Geol. Soc, xxvi,, 1870, 

 pp. 231 and 232, 



,, proboscidea, Eth. fil.. Cat. Austr. Foss., 1878, p. 109. 



Obs. — There are two right valves in our Collection, the largest 

 is four and a half inches across both diameters, and the other is 

 but slightly less, four inches by four and a half. The specimen 

 figured (PI. iii.) is the better of the two, and from it the following 

 facts are chiefly gained : — 



The valve is suborbicular, decidedly inequilateral, only moderately 

 convex, and with a short cardinal margin, but not shorter in pro- 

 portion than that figured by Morris and Lycett from the Great 

 Oolite of Minchinhampton. The anterior auricle is practically 

 undeveloped, and the anterior margin oblique to the cardinal 

 margin. The posterior auricle is triangular and comparatively 

 small, separated from the body of the valve by a well marked 

 groove ; the posterior end as it approaches the margin is some- 

 what flattened. The posterior margin is oblique, but not 

 emarginate. There are nine well developed cost;© and an in- 

 dication of a short tenth, sharp and ridge-like, rising into nodose, 

 fistulous projections, or short tubes, at the intersections of the 

 cosfcjfi by the concentric lamellae, which vary much in their distance 

 apart in the two specimens — wide apart in one, moderately close 

 in the other. The fistulous spines project beyond the ventral 

 margin, which is regularly rounded. The intercostal spaces are wide 

 and concave in the centre of the valve, becoming flatter towards 



