ERRATA AND ADDENDA. 



Page 55, line 15, for 1854 read 1855. 



Page 55, line 16, for Horticultural read State Agricultural. 



Page 60, in second table, Illinois, for 240 read 241 . 



Page 65, first line above foot-note, for ventricosa read ligamentina. 



Page 72, line 9, for imbecilis read imbecillis. 



Page 79, line 19, for asperimus read asperrimns. 



Page 80, above Quadrula rubiginosa insert Section Fusconaia Simpson. 



Page 76. The record of Calkins for Margaritana margaritifera is without 

 doubt erroneous and should be eliminated. This species is not found in Illinois. 



Page 95. Pomatiopsis sheldonii Pilsbry should read Amnicola sheldonii and 

 should be transferred to the genus Amnicola on page 93. 



Page 100. Physa gyrina oleacea Tryon is the immature stage of Physa gyrina. 



Page 103. Lymncea tazewelliana is a synonym of Lymncea parva. 



Page 105. Lymncea palustris michiganensis is the immature form of Lymncsa 

 reflcxa. 



Page 106. Lymncea reflexa iowensis and Lymncra reflexa crystalensis are 

 synonyms of Lymncea reflexa. 



Page 112, line 6 from bottom, for gouldi read goiddii. 



Page 114, line 5 from bottom, for juxtigens read juxtidcus. 



Page 115, line 2 1 , for Witter read Walker; line 23, Polygyra sayii Binney should 

 be changed to Polygyra sayana Pilsbry. 



Page 116, line 1. Polygyra cxoleta Binney (1885) should be changed to 

 Polygyra zaleta Binney (1837). 



Page 117, line 11 from bottom, for leai read leaii; line 3 from bottom, Poly- 

 gyra monodon fraterna is a good species and should read Polygyra fraterua. 



Page 119, foot-note. A specimen of alliarius in the collection of Mr. Aldrich, 

 received from Calkins, proves to be draparnaldi. 



Page 121, line 3 from bottom, for Champaign read Piatt. 



Page 122, line 12 from bottom, for Pyramidula striatella Anthony read Pyra- 

 midula cronkkitei anthonyi Pilsbry; line 4, for Held read Hald. 



Page 123, for Helicodiscus lineaius Say read Helicodiscus paralLlus Say. 



Page 162, line 7, for glandidosa read linearis. 



Page 171, line 17, for riparia read vulpina. 



Page 176, line 8 from bottom, for canadense read majus. 



Page 180, line 9, for virginica read virginiana. 



Page 221, line 6 from bottom, for rectangulus read rectangularis. 



Page 226, line 3, for fasciatits read fasciata. 



Page 239, line 11, strike out Lake Co. entry. 



Page 246, lines 6 and 7, and page 248, lines 1, 14, 20, and 23, for Oenothera 

 read Onagra. 



Page 248, line 4, for Candida Horn substitute n. sp. 



