116 THE NAUTILUS. 



Strobilops affinis (Pils. or near), mostly juv. and adolescent, few 

 mature. 



Bulimulus dealbalus mooreanus (W. G. Binn.?), a few juv. 



Polygyra, a few juv. 



Pupoides marginaia (Say), about 30 or more, juv.; generally small 

 (larger specimens probably retained on the sieve). 



Bifidaria corticaria (Say), two. 



B. tappaniana (Ad.), numerous ; part are quite small and low 

 (f. curtd). 



B. pentodon (Say), numerous and somewhat variable ; generally 

 small. 



B. pentodon floridana (Dall), a few and intermediate forms. 



B. holzingeri (St.), one. 



B. procera (Gld.), about 60. 



B. duplicata (St.), new, abundant; somewhat variable as to size ; 

 brown to light horn to colorless (albino). 



This Bifidaria has been known for many years, but was not pub- 

 lished. It is much like B. procera cristata Pils., averaging slightly 

 smaller, but differs mainly by its parieto-angular lamella, being 

 always long and complex, while that of cristata is shorter and ap- 

 parently simple, and it ranges nearer procera than cristata does. 

 The latter is known from New Mexico and Arizona, duplicata from 

 New Mexico to Texas (southwest, south and north) to Kansas. 

 Among the present material not one specimen was seen which even 

 approached cristata. More details in regard to the relations of these 

 and other Blfidarice of the group will be given elsewhere. 



B. hordeacella (Pils.), abundant ; mostly of the typical form, but 

 somewhat variable ; some specimens quite small with fewer whorls ; 

 a few are albinos. One specimen is reversed (sinistrorse). 



B. contracta (Say), abundant, with little variation. 



B. armifera (Say), a few juv. only. 



Vertigo miliutn (Gld.), 2. 



V. rugosula (St.), one ; known from Florida to southern Texas. 



Carychium cxiguum (Say), about 20. 



G. exile (Lea). 



Lymn&a (Galba) parva (Lea?), a few. 



Lymnaa (Sp.), one, juv., very small. 



Planorbis parvus (Say), a few dozen. 



P.carus P51s& Ferr. (?), 2 juv.; somewhat like parvus, but smaller 



