FAMILY TURBINID^E PALUDINA. 85 



upper part of the body-whorl forms a sort of shoulder with the suture. Like other specimens 

 of disscisa, the apex is often truncated, and some of the specimens were filled with young 

 shells. 



In my notes, I had marked specimens from Wolcott creek, Wayne county, as P. heros, 

 with the following characters : " Shell subconic, solid ; whorls 5-6, with moderate vertical 

 wrinkles and revolving striae, becoming few and obsolete on the body-whorl ; suture very 

 deeply impressed ; apex depressed, polished ; aperture subelliptic, narrowed above. Color, 

 whitish, but covered with an olive-green epidermis ; aperture within whitish, with a slight 

 reddish or bluish hue. Length, 1'5; diameter across the aperture, - 8." The enormous 

 size of these specimens, and the absence of banded stria? except on the body-whorl, induced 

 me at first to consider them as distinct; but on reexamination, I refer them to this species. 



Paludina isogona. 



PLATE VII. FIG. 133. 



(STATE COLLECTION.; 



P. isogona. Say, Des. terr. and fluv. shells, p. 19, 

 P. pallida ? Lea. 



Description, Shell short, subglobose ; surface polished with minute lines of growth. 

 Whorls four or five, rounded, rapidly decreasing to the apex ; body-whorl ventricose : suture 

 distinct. Aperture oval, angulated above, reflected on the pillar-lip, partially concealing the 

 umbilicus : outer lip slightly everted at the base. Aperture nearly twice the length of the 

 spire. Apicial whorl minute, scarcely elevated. 



Color. Olive-green. 



Length, 0"25; of aperture, - 15. 



I have received specimens of Paludina from the western part of this State, labelled 

 " isogona, Say ;" which, I am informed, is identical with P. ■pallida of Lea. I have not 

 been able to find descriptions of the latter ; but to avoid burthening the systems with a new 

 name, I prefer to adopt that assigned to it by Say. 



(EXTRA-LIMITAL.) 



P. transversa. (Say, Des. terr. and fluv. p. 20.) Shell transverse, depressed-orbicular: spire convex. 

 Whorls three and a half, with numerous minute slightly elevated revolving lines; suture not widely 

 indented; body- whorl very convex, short ; umbilicus small. Opercle pale fulvous. Greatest width, 

 0*4. Louisiana. 



P. interttxta. (Id. 1. c. p. 20; Am. Conch, pi. 30, figs. 3-6.) Shell subglobose, wrinkled, and 

 with minute, very numerous obsolete revolving deciduous lines: spire depressed, conic, obtuse, 

 truncated, eroded at tip. Whorls nearly four ; suture rather deeply indented ; umbilicus closed by 



