Occasional Papers of the Museum of Zoology 



Smaller Forms : 

 Amnicola liniosa 

 Amnicola lustrica 

 Ferrissia parallela 

 Planorhis parvus 

 Planorbis umbilicatcllus 

 Lymncea obrussa pcninsulcr 

 Lynincea humilisf 

 Planorbis exacuous 

 Amnicola limosa porata 

 Valvata tricarinata 

 Valvata sine era 

 Planorbis deflcctus 

 Pisidium compressiim 

 Pisidium variabile 

 Amnieola walkeri 

 Pisidium pauperculum 

 P. pauperculum crystalense 

 Museulium rosaceum 

 Pisid. variabile breznum 

 Pisidium afHne 

 Pisidium teuuissimum 

 Pisidium sargenti 

 L. humilis modicella 

 Pis. punctatum, simplex 



Shells Found only in 

 Marl : 

 Lymncca obrussa decampi 

 Pisidium mediatium 

 Valv. tricarinata confusa 

 Pisidium vesicular c 

 Pisidium peraltum, var. 

 pisidium splendidulum 

 Museulium, secure 

 P. compressum laevigatum 



