24 GASTROCOPTA, NORTH AMERICA, WEST INDIES. 



2(1. Form peninsularis, n. f. PL 2, fig. 8. 



The shells of peninsular Florida are slightly more fragile 

 than the typical form, and differ by having the inward con- 

 tinuation of the parietal lamella, beyond the second angular 

 bend, much lower and often detached from, the rest of the 

 lamella. Figured type is from Crystal River, Citrus Co., 

 Florida. 



2&. G. CONTRACTA CLiMEANA Vanatta. PI. 3, figs. 1, 4. 



"Shell similar to typical contracta (Say), but the parietal 

 tooth lacks the inner continuation, being L-shaped (fig. 4). 

 Alt. 2.29, diam. 1.43 mm." (Vanatta). 



Southern United States: Gulf coastal plain from Alabama 

 to Texas, and lowlands of the Mississippi north to Arkansas. 

 Alabama: Blakeley and Simpson Island, Baldwin Co. (C. B. 

 Moore) ; Calera and Weturnpka (H. H. Smith). Mississippi: 

 Anderson Landing, on the Sunflower River near confluence 

 with the Yazoo, Sharkey Co. (type loc.), and O'Neil Land- 

 ing, Yazoo Co. (C. B. Moore). Louisiana: New Orleans (S. 

 N. Rkoads), Franklin and Morehouse Parishes (C. B. Moore). 

 Arkansas: Ashley and Arkansas Counties (C. B. Moore). 

 Texas: Navidad River bottom, Jackson Co. (J. D. Mitchell). 



Bifidaria contracta cUmeana Van., Proc. A. N. S. Phila., 

 1911, p. 525, f. 1-3. 



In its area this subspecies replaces G. contracta. The Flor- 

 idian form (peninsularis) in which the inner continuation of 

 the parietal lamella is weak or interrupted, forms a partial 

 transition between contracta and cUmeana. 



Series of G. holzingeri. 



The inner end of the parietal lamella curves strongly 

 towards the periphery, and its anterior end is produced for- 

 ward of the junction with the angular lamella, the two lamel- 

 la diverging forward, the whole, when viewed from the base, 

 shaped like a mirror image of the letter "y". Columellar 

 lamella thin, high, and curving down at the inner end. Pala- 

 tals on a callous ridge, as usual. 



The separation of parietal and angular lamellas anteriorly 



