488 The MoUuscan Family Planorhidae 



PLATE 126 



Sliells of Planorbidae 



1-5. Drepanotrcma castcuuonitcns (Pils. and Van.). Near Maldonado, Uiuguaj'. Tj-pe 

 locality. U.S.N.M., 151668. 



6. Drepanotrcma hofftnanni F. C. Baker. Isabela, Puerto Rico. Holotype. B3952. 



7-9. Drepanotrema hoffmanni F. C. Baker. Isabela, Puerto Rico. Paratypes. B3953. 



10-12. Drepanotrema hojfmanni F. C. Baker. Near San Juan, Puerto Rico. Age 

 variation. U.S.N.M., 420573. 



13. Drepanotrema kermatoide (Orb.). Puerto Haberton, Argentina. U.S.N. M., 362857. 



14-16. Drepanotrema kermatoide (Orb.). Lima, Peru. Type locality. Figure 14 shows 

 an immature specimen. LT.S.N.M., 20705. 



17-19. Drepanotrema ciiltratum anitense (Cooper). Laguna, Santa Rita, Lower Cali- 

 fornia. U.S.N.M., 129292. 



All figures are enlarged about four diameters 



