xviii The Molluscan Family Planorbidae 



In certain specialized areas of these three fields, the University col- 

 lections have assumed a significance greater than might be expected 

 in a small museum. The collections of Mollusca are especially rich 

 in representatives of the fresh-water and land Mollusca, the direct 

 result of Mr. Baker's active research program. Extensive field col- 

 lecting was particularly stimulated by his association with the 

 Natural History Survey of Wisconsin in the preparation of his ex- 

 haustive two-volume work on the Mollusca of Wisconsin (1928). 

 His long association and collaboration with the Illinois State Natural 

 History Survey gave him access to extensive collections, especially 

 in late years when he was engaged in an intensive field study of the 

 land snails of Illinois which culminated in the Fieldbook of Illinois 

 Land Snails published (1939) by the State Natural History Survey. 

 A revival of interest in researches on the archeology of the State by 

 the University resulted in amassing within the Natural History 

 Museum huge quantities of pottery and artifacts for the care of 

 which Mr. Baker became responsible. 



His early interest in the Pleistocene fauna was revived and. 

 stimulated by a cooperative program of studies inaugurated by the 

 State Geological Survey. Enormous series of Pleistocene material in 

 quantitative samples were studied by Mr. Baker, whose services in 

 cooperation with the State Geological Survey were recognized by his 

 appointment to the position of Consultant in Pleistocene Paleon- 

 tology on its staff (1919). The Pleistocene collections under this 

 joint arrangement between Museum and Survey assumed great im- 

 portance and wide reputation as repository of critical materials, and 

 numerous collectors throughout the country sent samples for critical 

 determination. Thus, at the time of Mr. Baker's death, the Pleisto- 

 cene collections, which are now deposited in the State Geological Sur- 

 vey, had become one of the significant study collections in this field. 



Mr. Baker's interest in research was deep and genuine, and the 

 esteem with which his results are held gives evidence of the effective- 

 ness of his activities in scholarly pursuits. His earliest studies on 

 Mollusca were, in keeping with that period, restricted largely to the 

 study of the shells but he early became an advocate of the study of 

 the soft parts of the living animal which produces the shell and the 

 volume which this sketch accompanies is the culmination of his pro- 

 gram of anatomical studies. New apparatus and improved optical 

 equipment made him often express the regret that he could not go 

 back and do again all the earlier studies which he carried on with 

 less adequate laboratory equipment. 



Early in his career as a student of Mollusca, Mr. Baker by his 

 own collecting and by personal exchange, began amassing a private 

 collection of fresh-water Mollusca. This collection centered around 

 his chief interest, the fresh-water pulmonate snails. The operation of 

 the old adage. To him who hath shall be given,' here finds exempli- 

 fication, for students of Mollusca regularly sent doubtful specimens 



