CTENOSTREON PECTINIFORMIS — ETHERIDGE. 13 



CTEiYOSTEEOiV PECTINIFORMIS, SCHLOTHEIM, an 

 AUSTRALIAN FOSSIL. 



By R. Etheridge, Junr., Curator. 



(Plate iii.) 



In 1870, the late Mr. Charles Moore, of Bath, England, recorded' 

 as a West Australian Oolitic species, Lima proboscidea, Sby., but 

 he neither described nor figured the shell. Less than three years 

 previously, the late Rev. W. B. Clarke did the same from infor- 

 mation supplied him by Mr. Moore.- As it is important that all 

 species common to the stratified deposits of this Continent and 

 other parts of the world should be accurately figured, quite as 

 much as those purely endemic, for the information of Australian 

 students of Geology, I take the opportunity in the present in- 

 stance of eftecting this through examples of this shell having 

 passed into the possession of the Trustees. 



The species was known to the older writers under two names — 

 Li77ia pectiniformis, described by Von Schlotheim in 1820, and 

 Lima proboscidea, by J. Sowerby in 1821, the latter therefore 

 becomes a synonym of the former,^ It also forms the second 

 described species of Eichwald's genus Ctenostreon} 



Eichwald very carefully and lucidly explains that Ctenostreon 

 unites the characters of the genera Ostrea, Fecten, Lima, and 

 Spondylus. The more or less inflated shell is lamellar, as in Ostrea 

 and Lima, more or less irregular in growth as in both the genera 

 just mentioned, but the costal are more uniform than those of 

 the Oyster. The valves are nearly equal, as in Lima, with large 

 auricles as in Pecten, and the costse are furnished with fistulose 

 spines similar to those of Spondylus. The shell was not self- 

 attached as in Ostrea, but like that of Pecten fixed by a byssus. 



The principal synonomy of the species is as follows : — 



1 Quart. Journ. Geol, Soc, xxvi., 1870, pp. 231 and 232. 



2 Quart. Journ. Geol. Soc, xxiii., 1867, p. 8. 



3 Bronn— Index Pal., Nomen., 1848, p. 647. 



4 Eichwald — Lethsea Rossica, ii., 1868, p. 455. 



