BIBLIOGRAPHY OF 1877. 107 



From investigations made it was found that in their youngest 

 state 2 per cent, of M. integer and M. rufus and about i^ of 

 M. decisiis were sinistral. _ Compared with specimens collected, 

 only about i-tenth per cent, would appear to survive to reach 

 maturity. 



The author accounts for sinistration and various malforma- 

 tions by the crowded position of the embryo. 



Tiberi (Dott. N.) — Cefelopodi, Pteropodi, Eteropodi, 

 viventi nel Mediterraneo e fossili nel terreno terzi- 

 ario Italiano, con aggiunte e correzione. — Cepha- 

 lopoda, Pteropoda and Heteropoda existing in the Mediter- 

 ranean or fossil in the Italian territories. 



Witter (Prof F. M.) — Land and freshwater mollusks of* 

 Muscatine County, Iowa. — History of Muscatine County, 

 8vo., 1879, p. 332 and 333. 



The list has no localities (simply indication of scarcity or 

 abundance) and includes 20 species or varieties of Helix, i of 

 Cionella, 4 of Pupa, 3 SiicciJiea, 1 Limax, i Tcbennophorus, i 

 Caryclmim, 4 Limncea, 3 Physa, 6 Planorbis, i Segmentina, i 

 Ancylus, i Valvata, i Lioplax, i Melantho, i Vivipara, 2 

 Amnicola, i Bythi?iella, 1 Sotnatogyrus, i Pkurocera, 3 SphcEriuvi, 

 I Pisidium, 1 7 Anodonta, 5 Margariiana, and 43 of Unio. 



Witter (Prof. F. M.)— Notes on Wyoming Hills.— A paper 



read before the Muscatine Academy of Science, June 2, 

 1879, 8vo., 4 pages. 



This paper includes notes on various species of subfossil 

 shells, and a few recent ones. Those cited include Limncza 

 desidiosa Say, Succinea obliqua Say, S. avara Say, Helix lineata 



