286 PROCEEDINGS OP UNITED STATES NATIONAL MUSEUM [1885. 



Subgenus Sayella. Dall. 



Shell small, thin, subfusiform; spire elevated, last whorl contracted; 

 nucleus immersed; columella continuous with the anterior margin of 

 the aperture, and twisted to form one strong spiral ridge entering the 

 volutions ; no ])anetal teeth or callus ; outer lip thin, sharp, without in- 

 ternal lir;x^, thickening, or denticulations. Soft parts unknown. Type 

 Leueonia HeniphilUi Dall. 



This section is distinguished by its characters from any other of either 

 group of the fomily. It seems nearest Blauneria by the characters of 

 the shell, but indicates a medium between that grouf) and Detracia. It 

 is named in honor of Thomas Say, the father of American malacology. 

 The confused state of the manuals of American land shells on the sub- 

 ject of the AtiricuUdw is my excuse for placing it in a grouj) where by 

 subsequent investigation I find it cannot remain. 



Sayella Hemphillii Dall. Plate 18, fig, 11. 



Leueonia Hemphillii Dall, Proc. U. S. Nat. Mas., 1883, p. 323, plate x, fig. 6, Dec. 



1883. 



Habitat. — Cedar Keys, Fla., on mudtiats, Hemphill. 

 Sayella Crosseana, n. s. Plate 18, fig. 10. 



Shell minute, slender, ivory white, with longitudinal subtranalucent 

 peucillings and a suffusion of dark brown on the columella, fading away 

 toward the periphery of the base ; whorls five and a half beside the 

 immersed nucleus, which is glassy ; surface polished, faint strife of 

 growth evident; whorls flattened, the last about half the length of the 

 shell, the aperture slightly contracted, or rather the coil of that part 

 more compact than the antecedent whorl ; suture very distinct, with 

 the whorl behind it a little swelled and the whorl before it smoothly 

 appressed; apical turns a little inflated; apex blunt, with the im- 

 mersed nucleus half buried in it; aperture simple, smooth, not very 

 sharp edged, the margin rounded into the twisted, thickened edge of 

 the columella ; base radiately striate imperforate. Lon. 2.5™™ ; lat. 

 1.0™«; aperture slightly oblique, 0.75™'". 



Habitat. — Florida, Col. E. Jewett, one specimen. This remarkable 

 little shell is about one-fourth the size of Cionella acicula Binney, which 

 name had been attached to it. Its relations are evident, the nucleus 

 and the twisted columella, the diminished last whorl, general form and 

 even the coluraellar coloration all repeat in miniature the characteristic 

 features of Sayella HemiiliilUi. It may be thought absurd to put such 

 a shell into a subgenus of Melampiis^ and it is possible that the subgenus 

 proposed may eventually take higher rank, but in the absence of any 

 knowledge of the soft parts, and of important characters in the shell, 

 it seems better to take a conservative course. From Ferussaeia, Acicula 

 and Geostllbia and their allies this little shell is distinguished by its 

 sinistral nucleus which places it in a widely different group. From 

 Blauneria its dextral shell and conchological features appear to sufifl- 

 cieutly distinguish it. It is named in honor of the distinguished French 



