II IviGNiTic Stage ii 



PLEUROTOMA. 



Pleurotoma mediavia, var., I'l. i, Ak- ^^■ 



Syn. /'. iiu\fiavia Har., Bull. Am. Pal., vol. i, p. 193, pi. 17, fig. 16. 



Harris' original description. Lor. cit. 



Reference was made in the original description to a form of 

 the Lignitic stage at Woods bluff which seemed very nearly 

 allied to the Midway type. The differences between the two are 

 chiefly: the larger size of the Lignitic form, its less number of 

 revolving striae and its rather more pronounced costse and a 

 slightly raised spiral band below the suture. The two can how- 

 ever be referred with safety to the .same species. The costae are 

 figured too strongly developed for the majorit}- of specimens 

 in our coUedlions. 



Localities. — Ala.: Woods bluff, abundant; 3 mi. S. W. of 

 Thomasville. 



Figured specimen. — Paleontological Musuem, Cornell Univ. 



PI. mediavia, var. equiseta, n. var., PI. i, fig. 19. 



Differs from mediavia by its greater size, its very much finer 

 costations, especially on the 4th embryonic whorl, its coarser 

 spiral lines which are more or less alternate in size and are 

 .strangely granular like the exterior of "rushes" ; the carination 

 on the upper whorls especially in the upper spirals is lower down 

 than in mediavia. Yet the two forms ha\'e a very similar 

 general appearance. 



This form is most strikingly similar to P. 7vateleti Desh., of 

 the Sables inferieurs at Cuise-la-Motte. So far as can be judged 

 from Deshayes' description and figure the only points of variance 

 are the proportion of the body whorl to the remainder of the 

 shell, and its .size. Our shell is not 51 mm. long nor is the body 

 whorl proportionally so large. 



Localities. — Ala.: Woods bluff ; Hatchetigbee. 



Type. — Woods bluff; Paleont. Mus. , Cornell University. 



Pleurotoma moniliata, I'l- i, fig- 20. 



Syn. P. viouiliata Heilp., Proc. Ac. Nal. Sci. Pliila., iSSo, p. 373. pi. 20, 



fig. 9- 

 P. moniliala A\{\., Ci^o\. Sur. .A.la., vol. i, 1SS6, p. 52, 



