44 IOWA ACADEMY OF SCIENCES. 



AQUATIC OR SUB-AQUATIC FORMS. 



Limncea rejkxa Say. Reported (2) 



lAmnoea pahistris Mull. Reported (2) 



Other Limncea (8) -. 567 18.3 750 



Physa gyrina Say (9) 1 1 2 



Physa heterostropha Say (9) 



Bulinus hypnorum (L) Binn. Reported (10) 



Planorbis parvus Say 5 5 



Planorbis trivolvis Say. Reported (11) 



Segmentina armiqera (Say) H. & A. Ad. Reported (12) 



Valvato tricarinata Say. Reported (2) 



Campeloma subsoUdum Anth Reported (13) 



Pisidium sp. (14) 2 2 



Unio undulatus Barnes 6 6 



Unio rubiginosus Lea 5 5 



Unio pustulosxhs Lea (15) 1 1 



Total aquatic forms 570 201 771 



TABLE II. 



List of fossil molluscs from the ^^ Post-pleiocene deposits'' ". 



Zonites fuliginosus (Griff.) Binn 



Zonites intertextus Binn. 



Zonites inornatus (Say) Biun. 



Zonites gularis (Say) Binn. 



Patula soUtaria (Say) Binn. '■. 



Slenotrema stenotrema (Fer.) Try. 



Triodopsis palliata (Say) Binn. 



Triodopsis obstricta (Say) Binn. 



Triodopsis infleda (Say) Binn. 



Mesodon elevata (Say) Binn. 



Mesodon exoleta (Binn.) Try. 



Helicina orbiculata Say ^'. 



TABLE III. 



List of Unios from modified Loess submitted by Mr. Bain. 

 These are all from near the mouth of the Broken Kettle, Plymouth 

 county, Iowa. 



Unio anoxontrides Lea. 

 Unio donaciformis Lea. 

 Unio elegans Lea. 

 Unio 2)ust'ulosus Lea. 

 Unio rubiginosus Lea. 

 Unio undulatiis Barnes. 



1. J. E. Todd, Proc. A.m. A. A. S., Vol. XX VIE. p. 6, from southwestern Iowa. 



2. G. C. Swallow, Geol. Sur. of Mo., Vols. I and II, p. 315, from Missouri. 



3. The eggs vary slightly in size. The smaller agree exactly with eggs of modern 

 P. striatella. The larger may belong to another species. 



4. R. E. Call, Oa the Loess and Assorted Deposits of Des Moines, pp. 14 and 17; from 

 Des Moines Iowa. P. M. Witter, Rep. U. S. Geol. Sur. Vol. XI. p. 47. ■ 



5. These lots include Pupa pentodon, Vertigo ovata, etc., the greater part consisting 



