I20 



Bulletin 4 ' 2313 i^ 



umbilicus proportionally large, entirely destitute of a callus, the 

 volutions being distinctl}^ visible to the apical one; aperture semi- 

 lunate, the inner lip spreading somewhat on the preceding 

 volution, opposite the umbilicus it is thin and emarginat^; outer 

 lip sharp; surface polished. 



"This beautiful little shell differs from anj^ described species, 

 in the deep channelling of the suture and the characters of the 

 umbilicus. 



''Locality. — Nine miles below Prairie Bluff, Ala." 



Localities. — Alabama: yi mi. W. of Graveyard hill; Matthews' 



Landing. 

 Type. — Hall collection. 



AM AURA. 

 Ainaura {Aniaicropsisf) tombigbeensis n. sp., PI. 12, fig. 22. 



Specific characterizatio7i. — Size and general form as indicated 

 by the figure; non-umbilicate; shell very thin and fragile, marked 

 by very fine, even lines of growth and by a vast number of fine, 

 even, revolving, incised lines, tending slightly to alternate in 

 depth about the umbilical region; suture distinct, whorls slightly 

 shouldered below the suture, two or three stronger revolving 

 lines on this humeral zone; lines of growth when passing down- 

 ward from the suture, are directed slightly backwards as com- 

 pared with the axis of the shell. 



Localities. — Alabama: 4 mi. below Black Bluff, Tombigbee 

 river; i mi. N. of Midway. 



Type. — Paleontological Museum, Cornell Univ. 



SCALA. 



Scala sp, PI. 12, fig. 23. 



A specimen of this genus was found by the writer in a collec- 

 tion from near Olsen's switch, a few miles southwest of lyittle 

 Rock, Ark., and was figured in vol. ii, Geol. Surv. Ark., 1892, 

 pi. 3, fig. 2, and is figured herewith. Last summer other, larger, 

 but more imperfect specimens were found 3^ mi. W. of Prairie 

 Bluff, in bed <?, at the very base of the Midway. They seem to 

 belong to the same species as the Arkansas specimen but are 

 about % inch in diameter at base. 



SOLARIELLA. 



Solariella alabainensis, PI. 12, fig. 24. 



