Macrostomum sensitivum Silliman, 1884 | 1915-1917 | | | pond. |
Mesostoma angulare Higley, 1918 | 1915-1917 | | | from the Illinois River at Havana. |
Prorhynchus applanatus Kennel, 1888 | 1915-1917 | | | Collected during the month of February, 'from under ice, individuals of this species appeared crawling in masses of Cladophora. |
Typhloplana viridata (Abildgaard, 1789) | 1915-1917 | | algae | taken from algae close to the bottom in April and occasionally in the summer and fall. Many individuals. |
Gyratrix hermaphroditus Ehrenberg, 1831 | 1915-1917 | | algae | July. Frequent 'in nearly all of the collections made from the many sloughs and overflow waters along the Illinois river.' |
Macrostomum album Higley, 1918 | 1918 or earlier | | | ponds near Havana. |