ILLINOIS STATE GEOLOGICAL SURVEY 



Significant assemblages of type specimens 

 of species described by Baker are housed at 

 the Chicago Museum of Natural History, 

 the Chicago Academy of Sciences, the Uni- 

 versity of Wisconsin, and the University of 

 Illinois. Baker customarily deposited para- 

 typical specimens of new species in the Acad- 

 emy of Natural Sciences of Philadelphia. 



There are no less than three collections of 

 Mollusca at the University of Illinois — one 

 in the Museum of Natural History, one 

 forming part of the collections of the Nat- 

 ural History Survey, and one, composed 

 largely of molluscan fossils from Illinois, in 

 the paleontological collections of the Illinois 

 State Geological Survey. Type specimens of 

 species described by Baker are found in all 

 of these collections, and undoubtedly there 

 are types in still other collections, probably 

 many in those acquired by the Smithsonian 

 Institution. 



The type specimens of the many species 

 and subspecies described by Baker are widely 

 dispersed. It therefore seemed desirable to 

 make a permanent record of the type fossil 

 gastropods in the paleontological collections 

 of the Illinois State Geological Survey. The 

 type specimens are listed alphabetically under 

 the name combination used at the time of 

 their description. When the name combina- 

 tion in common use today differs from the 

 original, the present name has been placed 

 beneath the original name. This procedure, 

 however, is not to be construed as a syste- 

 matic revision of the several species con- 

 cerned. The taxonomic validity of the species 

 and subspecies listed here is not under con- 

 sideration in this paper. 



Age designations of the sediments from 

 which the fossils came are given as they were 

 indicated by Baker. Concepts of Pleistocene 

 stratigraphy have evolved greatly since Baker 

 made his collections but verification of their 

 stratigraphic placement was not attempted in 

 this report. 



Catalog numbers of the Illinois State Geo- 

 logical Survey are indicated by the symbol 

 ISGS ; numbers of the Academy of Natural 



Sciences of Philadelphia, where Baker habit- 

 ually deposited paratypes, are indicated by 

 the symbol ANSP. 



DESCRIPTION OF FOSSILS 



Amnicola greenensis Baker, 1928 



Plate 1, figure 9 



Paratypes: Two specimens, cat. no. 

 Z16222, ISGS. 



Original description: Wisconsin Geol. and 

 Nat. Hist. Survey Bull. 70, pt. I, p. 113, pi. 

 VI, figs. 32, 33. 1928. 



"Shell large for the genus, rather solid, 

 turreted ; surface smooth, with rather coarse 

 lines of growth; spire elevated, conic, longer 

 than aperture; whorls 5%, flatly rounded, 

 somewhat shouldered just below suture, 

 which is deeply impressed or even channelled ; 

 whorls rapidly and regularly increasing in 

 diameter; nucleus small, finely granular, 

 rounded, of one whorl, well raised above the 

 second whorl ; aperture ovate or roundly 

 ovate, angled above, the peristome continu- 

 ous, thin, appressed to the body whorl near 

 the upper part of the aperture ; base rounded, 

 with a well-marked, narrow and deep um- 

 bilicus." 



Length, 5.3 ; width, 3.5 ; aperture length, 

 2.3; width, 1.6 mm. Figured paratype. (Bak- 

 er's measurements.) 



Type locality: Green Lake, off Sherwood 

 Forest Hotel, Green Lake County, Wiscon- 

 sin. 



Collector: Wisconsin Geological and Nat- 

 ural History Survey party, 1921. 



Age designation: Pleistocene, Late Wis- 

 consin. 



Remarks: The holotype, no. 4544, is in 

 the University of Wisconsin collection. 



Amnicola lustrica gelida Baker, 1921 

 Amnicola gelida Baker 



Plate 1, figure 14 



Holotype: Cat. no. P926, ISGS. 



Original description: Nautilus, v. 35, p. 

 22, July 1921. 



"Shell differing from lustrica in being nar- 

 rower, with more convex whorls, more deep- 



