251 lyiGNiTic Stage 59 



Protocardia virginianaf Har., Proc. Acad. Nat. Sci. Phila. 1896, 

 p. 475, pi. 20, figs. 7, 8. 



Conrad first refers to the typical form of leriis as follows: 



" A species of G?r^/2^;« very nearly allied to this \_P. nicol- 

 letti ] , I formerly believed to be the same ; but it accompanies a 

 different group, and presents variations entitling it to be a spe- 

 cific distinction. 



" It is from Pamunkey river, Va. 



"Compared with C. nicolletti ; umbo less inflated, posterior mar- 

 gin oblique, shell proportionally longer, and the radiating lines 

 22 ; in the other 25. The posterior cardinal tooth larger, &c. It 

 may be named C. leney 



In 1864 Conrad evidently forgot that he had already named 

 this species and accordingly described and named it this time as 

 Protocardia virginiana. He gives the same locality, Pamunkey 

 river, and remarks that "the species is smaller and proportionally 

 longer than P. nicolletti with a smaller umbo. "Also "height i>^ 

 in.; length i 2-5 in." 



The variety from the Lignitic of Alabama is much smaller than 

 the Virginian type. Yet it seems somewhat more nearly related 

 to the latter than to nicolletti,h\it all may prove one and the same. 

 From nicolletti it differs not only in its smaller size, but, as stated 

 a year ago, by its smaller umbones, and also by the facfl that the 

 area with radiating lines not only , occupies the post-umbonal 

 slope, but has 8 or 10 lines on the lateral area of the shell. 



Localities. — Alabama: Woods bluff; Gregg's Landing; Bell's 

 Landing; Ozark; four miles above Hamilton Bluff, 

 Alabama River. 



Cardium hatchetigbeense, PI. 12, figs. 2, a. 



Syn. Cardium hatchetigbeense K^^.^^vW. i,(^&o\. Surv. Ala., 1886, p. 

 39. pi. 4, figs. 12, a, b. 



Aldrich's original descriptio7i. — "Shell large, subquadrate, ven- 

 tricose with about thirty-two ribs; ribs flattened oval, with the 

 scars of spines visible along their center; a few coarse, flattened, 

 triangular spines remaining on the posterior and anterior, largest 

 on the posterior, which is sub-truncate, the largest rib forming 

 the angle; marginal serrature largest at the angle. The flattened 

 spaces between the ribs are equal in width to the ribs and 

 nearly smooth, showing faintly the lines of growth. Cardinal 



