98 MAUL\'K AXD FISH i:h'Ii:S i 



5 GEORGE v., A. 1915 



VII. F:.mily unionidae. 

 I. (lonus Lampsilis. 



27. Lampsilis venlricosus, Barnes. 



28. Laiiipsilis lutcolis, Lamarck. 



28:i. Lampsilis lutcolis rosaccus De Kay. 

 J. Genus Anodonta. 



29. Anodonta grandis, Say. 



29a. Anodonta grandis footiana, Lea. 

 K. Genus Anodontoides. 



30. Anodontoides ferussacianus, Lea. 

 L. Geuns Unio. 



31. Unio complanatus, Solander. 



VIII. Family sphaeriidae. 

 M. Genus Sphaerium. 



32. Shpaerium simile, Say. 



33. Sphaeriiwi siriatinum, Prime. 



34. Sphaerium rhomhoideuyn, Say. 



35. Sphaerium (Musculium) securis, Prime. 



36. Sphaerium (Musculium) partumeium, Say. 

 N. Genus Pisidium. 



37. Pisidium abditum, Hald. 



• Family lymnaeidae. 



Represented by 13 species of Lymnea and Planorbis, together forming the third 

 of the total number of Molluscan species. 



Genus Lymnaea. 



Of six species identified, two, L. emarginata canadensis and L. Palustris are the 

 prevailing types. Both occur abundantlj^ L. haldemani was taken in only two 

 situations, although it was present in numbers L. decollata was taken in several 

 places, but nowhere abundantl3^ Of L. stagnalis sanctaemariae only six specimens 

 in all were obtained. L. columella was frequently found, but not in numbers. 



L. stagnalis sanctaemariae, Walker. The six specimens were identified as this 

 species and variety by Mr. E. G. Vanatta. The shortened spire corresponds to 

 the exposed situation in bare rocky channels. A light colored, transparent shell, 

 5 to 5^ rounded whorls with distinct suture. The aperture is broadly ovate, the 

 edge of the lip thin, flared anteriorly; slit-like umbilicus widely open or nearly 

 closed by the callus. (PI. XI, Fig. 18). 



L. (Galba) decollata, Mighels, occurs on rocky shores and in shallow rocky 

 bays of outer islands. Stout, nicely formed little shell, rhomboidal in outline 

 when viewed facing the aperture. Large body whorl, expanded aperture and short, 

 sharp spire. Whorls 3. Color brownish horn, tinged with green, apical whorls 

 darker, white varical thickenings on body whorl. In comparison with L. emargi- 



