Pleistocene Snails from San Patricio County, Texas 47 



souri; Tennessee, and northern Alabama (Pilsbry, 1946, p. 289). Retinellu in- 

 dentutu is known from the entire state of Texas (Strccker, 1935, p. 24). 



Ecology. Retinellu indentata is a cosmopolitan species. Baker ( 1939, p. 71 ) 

 discussed the ecology of R. indentata as found in Illinois: "It may be found living 

 in almost every county in the state. It is found in the river valleys, in wooded 

 areas and in former prairie lands, associated with Retinellu electrinu, Zonitoidcs 

 arboreus and other small snails. Its most favorable habitat, like that of so many 

 small snails of the state, is in woodlands of oak, elm, maple, and hickory. It may 

 be found under loose bark, woodland debris and fallen limbs of trees." 



Table 17. Measurements of Retinella 



indentata in mm. 







Section 



and bed Max. 

 Specimen nos. Length diam. 



Min. Apert. 

 diam. height 



Apert. 

 width 



No. of 

 whorls 



72, PL 2, fig. 8 2,5 2.7 4.5 



3.9 2.0 



2.5 



4 







Remurks. Retinellu indentutu is known from the Yarmouthian to the Recent 

 (Forsyth, 1958, p. 8). The species was recorded in Texas for the first time as a 

 fossil ( Wisconsinan ) by Conkin and Conkin (1962, p. 348). Conkin and Conkin 

 (1961, p. 12) reported R. indentuta from the upper 30 feet (Wisconsinan) of the 

 loess at Vicksburg, Mississippi. 



Retinellu indentutu puucilirutu (Morelet) 

 PI. 2, figs. 9a, 9b. 



Description. Retinellu indentutu paucilirutu differs from R. indentuta in hav- 

 ing a larger umbilicus. 



Meusurements. Measurements for Retinellu indentutu puucilirutu are given in 

 Table 18. 



Distribution. This species is recorded as distributed from Guatemala north- 

 ward to southern Indiana (Pilsbry, 1946, p. 291). 



Ecology. This species is characteristically one of southern to south-temperate 

 zones. 



Remurks. Specific determination was made by Dr. J. P. E. Morrison. Re- 

 tinella indentutu puucilirutu has been recorded from the loess at Helena, Ar- 

 kansas (Shimek, 1917), Natchez (Shimek, 1902), Vicksburg (Shimek, 1902 and 

 Richards, 1938), and at Tunica, Louisiana (Richards, 1938). 



Table 18. Measurements of Retinella indentata paucilirata in mm. 



Specimen 



Section 



and bed Max. Min. 

 nos. Length diam. diam. 



Apert. 

 height 



Apert. 

 width 



No. of 



whorls 



71, PI. 2, figs. 9a, b .. 



.. 2,5 2.5 3.7 2.9 



1.4 



1.9 



sy 4 





Stenotremu leui aliciae (Pilsbry) 

 PI. 1, figs. la-c. 









Description. Specimens are larger than those described from Michigan and 

 Ohio by Pilsbry (1940, p. 680). 



Measurements. Measurements for Stenotremu leui aliciae are given in 

 Table 19, 



