6 THE NAUTILUS. 



" desidiosa Say. Winnipeg. Also by Christy. 

 " humilis Say. Winnipeg. Also by Christy and Dawson. 

 Physa heterostropha Say. On all the lists. Quite uncommon here. 

 ampullacea Gould.? (Dawson.) 

 " anciliaria Say. Lake of the Woods (Dawson). Also rarely 

 at Winnipeg. 



ApJexa hypnorum L. On all lists. Usually a fine shell here. 

 Planorbis corpulentus Say. Lake of the Woods (Dawson). 

 " trivolvis Say. On all the lists. 



" macrostomus Whiteaves. Lake of the Woods (Dawson). 

 " hie arinatus Say. (Bell and Dawson.) 

 " campanulatus Say. Winnipeg, also by Bell and Dawson. 



" exacutus Say. Winnipeg, also by Christy, Dawson and 



Holland. 



Planorbis albxs Mull. (Holland and Taylor.) 

 " parvus Say. On all the lists. 



" umbilicatellus Ckll. (umbilicatus J. W. Taylor.) Bran- 

 don (Christy, etc.). 



Planorbis cristatus L. A pair from this place, identified by Dr. 

 Sterki. 



Planorbula armigera Say. On all the lists. 

 Ancylus parallelus Hald. (Christy & Dawson.) 

 " rivvlaris Say. (Dawson.) 



NEW SOUTHERN UNIOS. 



BY BERLIN II. WRIGHT. 



N. Harperi, sp. nov. 



Shell smooth, with slightly elevated growth lines, black towards 

 the umbos and tinged with red towards the base. Shining above, 

 rayless, oblique or very inequilateral. Umbos elevated and nicely 

 rounded; substance of the shell moderately thick, thinner posteriorly; 

 bluntly pointed behind with an inclination to biangulation. Dorsum 

 slightly arched, ligament red, basal margin slightly curved ; umbonal 

 ridge rounded above and decidedly flattened out at the posterior ex- 

 tremity ; teeth double in the left and single in the right valve, cardi- 

 nals pointed, compressed and oblique, with a supplemental tooth or 

 pointed callosity in the right valve midway between the cardinal and 



