PHYSA. 



95 



Fig. 162. 



move than half the entire area of the shell ; fold well marked ; whirls 

 tiiree. Foreign Analogue. Amphipeplea involuta. 



This small species inhabits the submerged rocks in the 

 rapids at the mouth of Nolachucky River, in Tennessee, 

 under such circumstances as to convince me that it does not 

 breathe the free air. I procured but two individuals, the 

 shells of which are sufficiently n-anslucent to exhibit light 

 circular dots upon the black ground of the mantle — a com- 

 mon character in this genus. (^Ilaldeman.) 



Phijxa globosa, Haldejian, Mon. pt. 4, p. 4 of cover (1842) ; 



p. 38, pi. v, f. 10-12 (1843) ; Journ. Acad. Nat. Sc. Phila. VIII, 

 200 (1842) ; Pr. A. N. Sc. I, 78 (1841).— DeKay, N. Y. Moll. p. 81 

 (1843). 



Phjsella glohvsa, Chenit, Man. de Conch. II, 281, f. 3551. 



The description and figure given above are copied from Halde- 

 man, the latter enlarged. 



Physa 



globosa. 



Subgenus PHYSODON, Hald. 



Shell solid, smooth, elliptical ; outer lip thick ; columella 

 toothed. 



Fig. 163. 



Pliysa micrQ&tOMlti^ ITald. — Shell elliptic, composed of four flat- 

 tened whirls, separ^wd by a distinct but very shallow suture ; substance 

 of the shell thick ; spire shorter than the aperture, and ending in a point; 

 aperture narrow elliptic, with a continuous peritreme, and 

 the labium much thickened anteriorly ; columella with two 

 nacreous elevations orobtuse teeth. Color light brownish- 

 ochraceous ; columella and external periodical (varicose) 

 bands, white, whilst the corresponding internal bands are 

 chestnut. 



Kentucky and Ohio. 



Tliis is a remarkable shell, and readily distinguished from 

 all the Atnerican species of Physa, hitherto described, by the 

 teeth upon the columella. {Ilaldemun.) 



Phijsa microstoma, Haldeman, Mon. p. 39, pi. iv, f. 12-14 (1853) ; Suppl. 

 to pt. 1, p. 2 (1840). 



Physiodon microstoma, Chenu, Man. de Conch. II, 481, f. 3552. 



Fig. 163 is a fac-simile of one of Haldeman's. His description 

 is o-iven above. 



Physa 

 microstoma. 



Cat. No.jNo.ofSp. 

 <M9:, 1 1 



Locality. 

 Kentucky. 



1 From whom received. 



Type. 



