CARDIUM. 
On 
a) 
pl. 18, f. 187, 188), which has been termed Cardiwm Avolicum 
by Born, Chemnitz, Schréter, Wood and Lamarek. There can, 
indeed, be little if any doubt that the pectinatum of Linneus 
was either that shell or one most closely allied to it, despite of 
the reference to Gualtier (whose figure of a pectinated Cytherea 
was in all probability only quoted as illustrative of the peculiar 
style of sculpture). This citation and the ‘anus ovatus, im- 
pressus marginibus prominulis” are the chief objections alleged 
by Chemnitz against this identification. The “alba seu rubra” 
instead of ‘‘ maculata,’ the omission of all mention of the 
smooth anterior (in the Linnean sense) area (which might lead 
us to think of C. lyratum), and the utter disregard of the figures 
published by Bonanni (pt. 2, f. 91) and Lister (pl. 314, f. 150, 
reference to which is made by the younger Linné), form addi- 
tional objections to any positive determination of the species. 
Cardiunr vivgtretur. 
The generic location of this shell, which, although de- 
scribed at some length, has scarcely been satisfactorily identi- 
fied, was a matter of some doubt to Linneus himself, for in his 
own revised copy of the tenth edition of the ‘ Systema’ he had 
placed it in Mactra. I find no mention of it in the pages of 
Chemnitz: Schréter merely reproduces the original description. 
Bruguiére, followed by Dillwyn, hint at the possibility of its 
having been constituted from a specimen of C. edule var. glaucum, 
and Gmelin, whilst copying the language of Linneus, cites the 
C. rugatum (apertum of Chemnitz) as a variety. The “rugis 
transversis membranaceo-recurvatis’’ cannot, however, be 
affirmed with truth of either of these shells. Wood omits it 
as too ambiguous for determination. 
Since our author, who has transferred this species to Mactra 
in his manuscript, has likewise indicated his possession of it, 
recourse has been had to that tedious yet satisfactory mode of 
analysis (in default of any marked examples having been 
discovered) spoken of in the Preface, and as one shell, and one 
alone, in the entire collection will agree with the description, 
no reasonable doubt can be entertained of its typical authority : 
the name, however, cannot take precedence, for, without the 
