There are few published statements relative to the length of the annual period of activity; all records refer to _spinifer_. In Lake Maxinkuckee, northern Indiana, Newman (1906:128) wrote that individuals were first seen in early April on the lake shore in a weak condition with neck and legs extended, and were easily captured. Lesueur (1827:262) wrote that _spinifer_ in Indiana appears toward the end of April. Observations of Evermann and Clark (1920:592) in Lake Maxinkuckee, and Butler (1894:224) in east central Indiana concurred in finding that of all kinds of turtles there, softshells appeared last in spring and disappeared first in fall. Evermann and Clark found small softshells, benumbed or dead, along the shore as early as March 18 and also late in fall. The earliest observation for large softshells was April 29, and the latest was September 7; Butler found that these turtles rarely appear before April 15 and sometimes not until May 1. Cahn (1937:191) stated that softshells in Illinois hibernate toward the end of October and emerge in May or the latter part of April; the same author mentioned that in southern Illinois the species might remain sluggishly active all winter. In Ohio, Conant (1951:160) wrote that individuals were collected every month from March to October, and one was even taken in December, 1929, in northwestern Ohio. Wright (1919:8) mentioned observing softshells on April 20 and September 20 (presumably these were the earliest and latest observations of them) in Monroe and Wayne counties, New York. Blatchley (1891:34) listed dates of early and late activity as March 19 and December 11 for Vigo County, Indiana. Webster (1936:22) recorded the earliest and latest dates of collection of _spinifer_ in central Oklahoma as June 10 and November 8. Moore and Rigney (1942:80) found an individual of _muticus_ under six inches of ice in water about one foot deep on January 31, 1940 (Cimarron River, Payne County, Oklahoma). The published information suggests that the length of the normal annual period of activity of _spinifer_ in latitudes of about 40° and 43° is approximately five months, from April into September, depending upon the weather. There are numerous published statements to the effect that the period of hibernation is passed under a shallow covering of mud in deep water. Evermann and Clark (_op. cit._: 593) found a softshell (presumably in a quiescent state) on September 6 that was "buried up to its eyes in mud at the edge of Lost Lake." Softshells possibly hibernate in shallow water or in soft mud flats. Conant (_loc. cit._) found that captives would not hibernate in a pond in a zoo having a bottom of leaves. Food Habits