SOME NOTES OX RECENT MOLLUSCA OF OHIO. 



BY DR. V. STERKI. NEW PHILADELPHIA, O. 



The Land and Fre.sh Water Mollusca of North America 

 have been attentively studied by man}' ver}- able concholo- 

 gists. And yet our knowledge of them is still incomplete, 

 in different regards: 



1. There is no doubt but that quite a number of species 

 and varieties are still unknown, especially among the smaller 

 forms : 



2. As to the geographical distribution of a good part 

 of them very much is yet to be done; 



3. Many of those already described are still not or in- 

 sufficiently known as to their anatomy. 



Applied to the territory of Ohio, these points deserve 

 our special attention, and a few i\otes relating to them will 

 show in what direction our investigations should mainly be 

 directed, especialh- as to points 1 and 2, 8 being of a more 

 general character. 



Ad 1. It is significant that within the last three years, 

 three new .species of Pisidhim have been found in the Tusca- 

 rawas river, at New Philadelphia. Two of them. Pis. cruci- 

 atian and Pis. piinctatunr' are of very minute sizes, indeed 

 the smallest of all species hitherto known. The former was 

 first collected in 1S91, and has, so far, not been seen from 

 other places: the latter has been found also in Portage county, 

 on the watershed, in two streams, one tributary to the Ma- 

 honing, the other to the Cuyahoga river. The third species. 

 Pis. fallax (not yet published) first seen also in October and 

 November 1891, resembles Pis. compression Prime, with 

 which it lives in the same places, and has also been .seen from 

 New York and New Jersey. The Pisidia and Sphaeria, 

 .should meet the special attention of all collectors. Encour- 

 aged and requested to do so by many prominent concholo- 

 gists, such as MM. E. W. Roper, Hy. A. Pilsbry, Wm. H. 



•■■ They will be published with figures iu the January issue of the 

 Nautilus." 



