IV 



ON A NEW SHOVELNOSE STURGEON FROM 

 SIPPI RIVER. BY S. A. FORBES and R. E. page 



RICHARDSON. Plates.) May 15, 1905 37-44 



" 



38 



ins albtts, sp. nov 38 



mparison of Parascaphirhynchus a/bus and Scaphirhynchus 



^ () 



Ki hirhynchus and related Genera 41 



hy 42 



ARTICLE V. NOTES < ).\ SPECIES OF NORTH AMERICAN OLI- 



hH.ETA. V. THE SYSTEMATIC RELATIONSHIPS OF 



LUMBRICULUS (THINODRILUS) INCONSTANS (SMITH). BY 



FRANK SMITH. December 26, 1905 45-51 



. >n with Trichodrilus and Lumbricidus varicgatus 45 



All itunen Gland 45 



- ; lermiducal Pores and Gonads 46 



46 



Vascular System 47 



athecae 47 



Atrium and Penis 48 



important Characters 48 



Lumbriciilus 49 



iegatus 49 



inconstans 50 



Summary 50 



Literature cited 51 



ARTICLE VI. A CATALOGUE OF THE MOLLUSCA OF ILLINOIS. 



BY FRANK COLLINS BAKER. (1 Map.) September, 1906 .. . 53-136 



Introductory 53 



iry 53 



Acknowledgments 53 



Topography 54 



Literature 55 



New Species and Varieties described from Illinois 56 



Molluscan Fauna of Illinois discussed 57 



Fluviatile Mollusks 57 



Terrestrial Mollusks 59 



Numerical Comparison of Illinois Mollusks with those of other States. 59 



Geographical Distribution 61 



Systematic Catalogue of Species 63 



Bibliography 124 



Index j 3_j. 



