NOTE ON THREE SPECIES OF PELECYPODS. 



By EDGAK a. smith, I.S.O., 



British Museum (Natural History) London. 



1— Crassatellites ponderosus (Gmeiin). 



In the Proc. Limi. Soc. N.S.W. 1904, part i, Mr. C. Hedley, in a valuable 

 paper on some Australian Mollusca, has ([uestioned the propriety of calling 

 a species of Cransafel/ifes, G. kitKjh-ola, Lamarck, substituting the name of 

 ponderosus of Gmeiin. 



This species was founded by the latter author on figures and a descrip- 

 tion publi.shed by Chemnitz in " Der Naturforscher," Stuck xix (1783) pp. 

 185, 186, pi. viii, and in the "Conchylien Cabinet " (1784), vol. vii, pp. 61, 62, 

 pi. Ixix, figs. A — ^D, the latter figures being rough copies of those in " Der 

 Naturforscher." 1 feel quite certain that the shell figured by Chemnitz is not 

 the same as the well-known 0. kintjicola, Lamarck. Li the first place the 

 form is different, being shorter and squarer, and the posterior end is both 

 less narrowed and prolonged. Then again, in kingicola the posterior ad- 

 ductor scar is invariably of a very dark brown colour which is not mentioned 

 by Chemnitz and is not likely to have been overlooked by him if it existed 

 in his specimen, and still further, why should the artist draw a crenulated 

 edge to the valves, a feature non-existent in C. kimjicola, if it were not present 

 in the shell before him, and why did Chemnitz write " margine subcrenulato " 

 in his latin diagnosis, and refer, in his further description, to "den feinen 

 Kerben ihres Randes und Umrisses " ? 



Mr. Hedley states that Gmeiin incorrectly gives " margine crenulato " 

 as a character, and that his error arose from the fact that Chemnitz's artist 

 used a dotted line to represent the inner edge of the valve-margin. He also 

 observes "the pallial line, which could hardly be 'crenulated,' is indicated 

 by a similar dotted line." Mr. Hedley never saw the original figures in the 

 " Naturforscher," and apparently could not have closely followed the descrip- 

 tion giveii by Chemnitz or he could not have made these statements. GmeHn 

 evidently had both seen the figures and read the description, and consequently 

 was quite justified in writing " margine crenulato." For the information of 

 those who may not have the opportunity of seeing the work in question, I 

 may mention that the pallial line is properly drawn in both figures of the in- 

 terior of the valves and not dotted as it appears in the rough copies in the 

 •'Conchylien Cabinet." 



I am of opinion that Lamarck, followed by Deshayes and others, was 

 quite right in considersng Gmelin's species the same as the Grignon fossil, 

 G. tumida, Lamarck. It agrees in form, sculpture, the enormously thick 

 hinge and the crenulated margin. 



