102 



LAND AND FRESH-WATER SHELLS OF N. A. [PART II. 



Fig. 173. 



Bllliiius distortusj Haldeman. — Shell transverse, short, trans- 

 lucent and umbilicated ; composed of three very convex whirls, and hav- 

 ing a very deep suture ; spire pointed, shorter than the aper- 

 ture, which is oval, and almost cyclostomous, without any fold 

 upon the labium or columella. Color very light yellowish- 

 gray. Foreign analogue : P. (juihlin'jii, Sw. 



Near St. Louis : Mr. Emerson. Kentucky and Ohio. 



I am indebted to G. B. Emerson, Esq., President of the 



Boston Society of Na,tural History, for specimens of this curious 



shell, which were collected (by himself, I believe) near St. 



Louis. It is remarkable for the contorted spire and entire absence of a 



columellar fold. (^Haldeman.) 



Physa distorta, Haldeman, Mon. 35, jpl. v, f. 1-3 (1842) ; Suppl. to pt. 

 1, 1840, p. 2. 



Fig. 173 is a fac-simile of the outline of one of Haldemau's 

 figures. His description is copied above. • 



Spurious Species of Bulinus. 



Aplexa suturalis, Beck. Mexico. No description. Index, 117. 

 Bulinus fontimd is and var. canadensis, Beck; without description. 



117. 

 BuHnus pomilius, Conr., Beck, /. c. = Physa. 

 Bulinus crussula, Beck, p. 117 ; no description, and 

 Var. typica ( == P. heterostropha) ; 



b. striata ( = P. striata, Mke. ) ; 



c. minor ( = P. arctistropha, Cri.^t. & Jan). 



Bulinus subaratus. Beck, Ind. p. 118 = Phi/sa heterostropha? 

 Bulinus gyrimis. Beck, I, c, 118 ^ Physa gyrina, 

 Bulinus muugerae. See Bulinus aurantius. 



Index, 



Fossil Species of Bulinus. 



Dr. Meek furnishes me with the following list : — 



Aplexa longiusnda, Meek & Hayden, MSS. (^Physa lonrjiuscula, Pr. Phila. 



Acad. 18.56, 119.) 

 Aplexa subelongata, Meek & Hayden, MSS. {Physa suhelonqata, Pr. Phila. 



Acad. 1856, 120.) 



