TRANSACTIONS OF WAGNER 



127, pi. 7, fig. 5, 1824); Bronn, 1849, p. 455, cites it as a varietj^ of 

 Say's species.] There is no doubt of its identity with one of the varieties 

 of Ecpliora quadricostata of our Atlantic Miocene. 

 Figure 3, A, B. Modiola gigas Wagner. [Bronn, 1848, p. 736; 1849, p. 

 274.1 This differs a good deal from Modiola ducatelii Conrad (Fos. 

 Medial Tert, p. 53, pi. 28, fig. 2, 1840) in outline, though Professor 

 Wagner's specimen has been somewhat distorted by pressure. If the 

 differences are normal there is no doubt of the validity of both species. 

 Specimens somewhat approaching the figure of M. gigas have been 

 obtained from the Miocene of Maryland by the collectors of the Mary- 

 land Academy of Sciences. 



PLATE 3. 

 Fio'ure i, A, B. Chama agassizii Wagner. [Bronn, 1848, p. 282; 1849, P- 

 292.] The type in the Wagner collection appears to be a senile speci- 

 men of Chama corticosa Conrad (Am. Journ. Sci., xxiii., p. 341, July 



1833)- 

 Fio-ure 2. Cardiiim ingens Wagner. [Bronn, 1848, p. 282; 1849, p. 465.] 

 This is a fine species, seldom found in good condition, but abundant in 

 the Maryland Miocene. It appears to be identical with the shell described 

 as C. laqueatimi Conrad (Journ. Acad. Nat. Sciences, Phila., vi., p. 258, 

 1831 ; Fos. Medial Tert, p. 31, pi. 17, fig. i, 1838), though I have never 

 seen a specimen with so many as the forty-three ribs ascribed to laqite- 

 atum in Conrad's diagnosis. The number appears to be usually thirty- 

 six or thirty-seven. Under Cardiuin virginianinn in Conrad's Medial 

 Tertiary Fossils (part 2, 1840, p. 33) occurs the following note: "The 

 specimen figured belongs to the fine cabinet of William Wagner, Esq., who 

 procured it with other fine fossils in Virginia. He gave it the name of 

 C. ingens and read the description at a meeting of the Academy of Natural 

 Sciences in the winter of 1838-39. As I do not recognize a species until 

 the description appears in print, it is necessary to adopt the name under 

 which it was published in April, 1839." This appears to be one of those 

 cases in which Conrad exercised his unrivalled capacity for mixing things 

 up. It is probable that his note should have been placed under the de- 

 scription of C. laqueatum. It is useful in showing that Professor Wagner 

 read his account of these fossils as early as the winter of 1838-39, and 

 that the date of the plates may be as early as 1839. A cessation of 



