82 THE NAUTILUS. 



species. The catch of Unios at Cedar Bluff was eighteen species, 

 among them some riddles in Pleurobema, which at last account were 

 still making trouble for the Doctor. Out of the drift at the head of 

 the rapids we picked Spluzria, which Dr. Sterki has kindly identified 

 as Spheerium fabale Pme., S. solidulurn Pme., Pisidium virginicum 

 Gmel., P. compression Pme., and three individuals "apparently near 

 P. noveboracense Pine." The next morning I climbed the bluff and 

 found Polyyyra albolabris major, rugeli, thyroides, zaleta and steno- 

 trema ; Gastrodonta acerra and gularis ; Omphalina fuliginosa, Zoni- 

 toides arborea and the umbilicated form of Vitrea indent ata. The 

 weather had been dry for weeks, and the land mollusca had to be 

 dug for. I uncovered Lymneta obrussa and Succinea avara glued to 

 leaves in a dried-up brook. 



Our next jump was to St. Paul, Wise Co., Va., still on the Clinch. 

 Decided differences were to be remarked in the fauna. In the rapids 

 opposite Fink station, Russell Co., a mile or so above St. Paul, were 

 Fusconaia edgariana (Lea), Crenodonta undulata (Barnes), Ptycho- 

 branchus phaseohis (Hild.), and Nephronaias perdix (Lea), none of 

 which had appeared at Cedar Bluff. The Jo at this station was be- 

 ginning to assume nodules. One specimen equals lo lurida of 

 Reeve. Anculosa subglobosa Say, which at Cedar Bluff was wholly 

 without bands, so far as we noted, was almost universally banded in 

 the rapids at Fink. To me they seemed also to run larger. In the 

 material brought away from this place appeared Pleurocera tene- 

 brocinctum Anth. and P. opaca Anth. 



The following morning Dr. Ortmann went to Cleveland, Russell 

 Co., up the river, whence he returned aglow with enthusiasm over 

 the discovery of twenty-five species of Naiades, while I had a try for 

 land shells among the Russell county hills. The most interesting 

 observations were that the Polygyra appressa, rugeli and thyroides 

 of the region seemed to prefer the stray logs of the high pastures to 

 the woods, that the ratio of banded Polygyra profunda to unbanded 

 was 1 to 10, and that there thrived here a Succinea ovalis Say, of 

 quite surprising size, one specimen reaching 25 mm., the extreme 

 recorded by Binney. Though the dead of this species was plentiful, 

 only one living individual was found. In brooks fed by hillside 

 springs, I came upon a few specimens of Pomatiopsis cincinnatiensis 

 Lea, Paludestrina nicMiniana Lea, and Lymnsea obrussa Say. 



(To be concluded ). 



