GASTEEOPOBA. OP TUB LOWER GREEN MARLS. 121 



DOLIID'^. 

 Genus DOLIUM Lamarck. 



DOLIUM (DOLIOPSIS ?) MULTILIEATUM, n. Sp. 



Plate XV, Figs. 4-6. 



Shell, as known from an internal cast, small, Kubglobose or broadly 

 pyriform ; outer volution forming nearly the entire bulk of the shell ; spire 

 low, rounded, the whole composed of about three whorls; sutures in the 

 cast quite strongly marked; beak of the last volution short and on the 

 back, scarcely distinct from the marginal lij), showing the existence of only 

 a very short canal; aperture large, fully five-sixths as long as the entire 

 length of the shell; columella showing only a moderate cavit}' by its re- 

 moval, but giving evidence of a projecting part near the lower end on the 

 inside; otherwise the cast shows iio twist of the columella; surface of the 

 cast marked by numerous spiral lines and furrows (about sixteen ridges can 

 be counted along the margin of the lip), and also by irregular transverse 

 wrinkles, parallel to the margin of the aperture; near the aperture, on the 

 last volution, a sharp constriction indicating a strong varix, as if for the 

 thickening of the outer lip, over which the spiral lines pass, and there is 

 a line of small pits, one on each rib, indicating node-like granules. 



The cast presents every appearance of a species of Doliwrn, as far as a 

 cast would preserve the features of a shell of that genus. The canal, of 

 course, would not show the twisting or tortuous character on a cast, unless 

 the matrix of that part was preserved, which is not the case in the present 

 instance. It may be that it should be referred to Conrad's genus Doliopsis, 

 but his figure would lead me to consider it much more nearly a true Bolium 

 if there is any difference of generic importance between them. As I do 

 not find that Conrad even charactei'izes the genus, I can not tell what its 

 features may be except from his figure on Plate x. Fig. 15, vol. 1, Am. 

 Jour., Conch. ; not having seen his types, I was at first inclined to consider 

 this shell as congeneric with Meek's genus Pseudobuccinum, but on remov- 

 ing the inner whorls of the cast I find there is a solid axis, indicating the 

 existence of a true columella, although rather slender, which feature Mr. 



