392 THE CHICAGO ACADEMY OF SCIENCES. 
Planorbis deflectus. Bowmanville. 
Planorbts bicarinatus. Edgebrook, Avondale, Lincoln Park, 
Cte: 
Somatogyrus subglobosus. Lincoln Park. 
Valvata sincera. Maywood, Riverside and Salt Creek. 
p- 33. Economy or THE Motiusca. Leucochila fallax Say 
has been found injurious to the strawberry, eating the stems 
and crowns, rasping off the outer coating (epidermis) and suck- 
ing the juices, thus causing the fruit to decay. Several thou- 
sand specimens were picked from a patch of strawberries, and 
forty specimens were found upon one plant.* 
p. 34. Under Statistics. No. 4. Comparison with Penn- 
' sylvania. Mr. Clapp writes the author that the number of spe- 
cies quoted from Allegheny County, Pa.,ismuchtoosmall. Mr. 
Clapp has very kindly forwarded a complete list of the Mol- 
lusks of Allegheny County, and the figures on page 34 must be 
changed to read as follows: families, 23; genera, 46; species, 
131; varieties, 4. 
p. 54. Anodonta foottana is now considered a variety of 
Anodonta grandis. 
p- 57. Alasmodonta rugosa Barnes should now be called 
Symphynota costata Rafinesque (Ann. Gen. Sci. Brux., Vol. V, 
p. 318, pl. Ixxxul, figs. 15, 16, 1820); vide Simpson. 
p. 58. Alasmodonta pressa should be called Symphynota com- 
pressa lea. 
p. 60. Alasmodonta complanata should be called Symphynota 
complanata. Alasmodonta should be changed to Alasmidonta, as 
spelled by Say in Journ. Phil. Acad., Vol. I, p. 459, 1818. 
p. 62. <Alasmodonta marginata Say should be changed to 
Alasmidonta truncata, B. H. Wright. (See The Nautilus, Vol. 
XI, p. 124, 1898.) The true marginata is confined to the Atlan- 
tic drainage. 
p. 63. Alasmodonta deltoidea should be called Alasmidonta 
calceola, the reference being Trans, Amer. Phil. Soc., Vol. II], 
p. 265, pl. iii, fig. 1, 1830. 
p. 71. Unto hildrethianus Lea should be changed to Hemz- 
lastena ambigua Say. The genus Hemilastena (Agassiz, 1852) 
Simpson, differs from Unio in the sculpture of the umbones 
and in the teeth. The gills are united to the mantle posterior 
to their ends. The name ambigua was used by Say in Journ. 
*Vide E. T. Cox, in the Amer. Nat., Vol. II, No. 12, p. 666, Feb., 1869. 
