24 



13. P. m or i forme, Lea. 



Trypanostoma moriforme, Lea, Proc. Acad. Nat. Sci., p. 172, 1862. Jour. 

 Acad. Nat. Sci,, v. pt. 3, p. 290, t. 36, f. 118. Obs., ix. p. 112. 



14- P. Pybasii, Lea. 



Trypanostoma Pybasii, Lea, Proc. Acad. Nat. Sci., p. 172, 1862. Jour. Acad. 

 Nat. Sci., v. pt. 3, p. 289, t. 36, f. 115. Obs., ix. p. 111. 



15. P. Showalterii, Lea. 



Trypanostoma Showalterii, Lea, Proc. Acad. Nat. Sci., p. 172, 1862. Jour. 

 Acad. Nat. Sci., v. pt. 3, p. 293, t. 36, f. 122. Obs., ix. p. 115. 



C. Angulate, striate below the periphery. 



16. P. Thorntonii,* Lea. 



Trypanostoma Thorntonii, Lea, Proc. Acad. Nat. Sci., p. 170, 1862. Jour. 

 Acad. Nat. Sci., v. pt. 3, p. 284, t. 36, f. 106. Obs., ix. p. 106. 



17. P. infrafasciatum, Anthony. 



Melania infrafasciata, Anthony, Proc. Acad. Nat. Sci., p. 57, Feb., 1860. 

 Binney. Check List, No. 148. Brot. List, p. 30. Reeve, Monog. 

 Melania, sp. 301. 



18. P. Postellii,t Lea. 



Trypanostoma Postellii, Lea, Proc. Acad. Nat. Sci., p. 171, 1862. Jour. Acad. 

 Nat. Sci., v. pt. 3, p. 286, t. 36, f. 110. Obs., ix. p. 108. 



19. P. incurvum,t Lea. 



Trypanostoma incurvum, Lea, Proc. Acad. Nat. Sci., p. 171, 1862. Jour. Acad. 

 Nat. Sci., v. pt. 3, p. 286, t. 36, f. 309. Obs., ix. p. 108. 



20. P. Alabamense, Lea. 



Trypanostoma Alabamense, Lea, Proc. Acad. Nat. Sci., p. 171, 1862. Jour. 

 Acad. Nat. Sci., v. pt. 3, p. 288, t. 36, f. 113. Obs., ix. p. 110. 



21. P. Florencense,|| Lea. 



Trypanostoma Florencense, Lea, Proc. Acad. Nat. Sci., p. 171, 1862. Jour. 

 Acad. Nat. Sci., v. pt. 3, p. 287, t. 36, f. 112. Obs. ix. p. 109. 



22. P. canalitium, Lea, 



Trypanostoma canalitium, Lea, Proc. Acad. Nat. Sci., p. 175, 1862. Jour. 

 Acad. Nat. Sci,, v. pt. 3, p. 292, t. 36, f. 121. Obs., ix. p. 114. 



23. P. Clarkii,ir Lea. 



Trypanostoma Clarkii, Lea, Proc. Acad. Nat. Sci., p. 171, 1862. Jour. Acad. 

 Nat Sci., v. pt. 3, p. 285, t. 36, f. 108. Obs., ix. p. 107. 



24. P. Anthonyi, Lea. 



Trypanostoma Anthonyi, Lea, Proc. Acad. Nat. Sci., p. 172, 1862. Jour. 

 Acad. Nat. Sci., v. pt. 3, p. 293, t. 36, f. 123. Obs., ix. p. 115. 



25. P. prasinatum, Conrad. 



Melania prasinata,** Conrad, Am. Jour. Sci., 1st ser. xxv. p. 342, t. 1, f. 

 14, January, 1834. Jay, Cat., 4th Edit., p. 274. Binney, Check List, 



* This species is shorter in the canal, has broader bands, and wants the tubercles ofmoniliferum, 

 which it otherwise much resembles, 



f Distinguished from infrafasciatum by its whorls being more flattened, and by its narrow 

 form. 



t Differs from Postellii by its singularly incurved edge of the outer lip. 



| Very distinct from the preceding two species in the more developed spire and canal. 



|j Inhabits the waters of Indiana, also. No. 20, (Alabamense) may prove to be the young of 

 this species. 



f Doubtfully distinguished from canalitium by its broader proportions, better developed carina 

 and recurved canal. 



** The figure given by Mr. Conrad is not a good representation of this species. 



