So far as reported, this species is confined to a narrow strip of territory running north for about eighty miles from the southern boundary of the state and drained by the Arkansas river. =3. Cambarus gracilis= Bundy. Specimens of this species are hard to obtain, and this doubtless accounts for its few localities. It is found in the territory drained by the Arkansas (1) as well as that drained by the Kansas river (2). In August, 1901, I found an adult female of _C. gracilis_ in a stagnant pond near Lawrence—the only time I have ever taken an adult specimen in open water during the summer. =4. Cambarus diogenes= Girard. Reported so far only from a limited territory along the Kansas and Missouri rivers, in the northeastern part of the state. As with _C. gracilis_, the difficulty of obtaining material probably accounts for the rarity of the reports on this species. =5. Cambarus immunis= Hagen. Mr. Crevecœur collected _C. immunis_ in a stagnant pond on the prairie near Onaga, Pottawatomie county, April 1, 1901. The pond had been in existence about six years, and had never been known to go dry. The nearest creek was about a quarter of a mile away. They were probably never connected when the water was high in the creek. No fish had ever been taken in the pond, but specimens of _Amblystoma tigrinum_ (green) were found. (_A. tigrinum_ and _C. immunis_ are sometimes found in the same ponds in Douglas county.) Among a dozen specimens given to me, some of the females were carrying eggs but none were noticed with young. Mr. Crevecœur drained the pond in obtaining the material, and was careful to secure a representative collection. If _C. gracilis_ were common in the region, it would not be improbable that females would be found in the pond at this time. Reports so far would indicate a distribution of this species from the Missouri river west along the Kansas and its tributaries nearly two-thirds the distance across the state. =5a. Cambarus immunis Hagen, var. spinorostris= Faxon. The limits of distribution are embraced within those given for _C. immunis_. =6. Cambarus nais= Faxon. So far as reported, this species is confined to the southeastern portion of the state, drained by the tributaries of the Arkansas river. =7. Cambarus virilis= Hogue. 23. Wakarusa river, Douglas county. 24. Bull Foot creek, Lincoln county. Taken under stones, in about six inches of running water. Miss Ella Weeks, coll. 25. Spillman creek, Lincoln county. Under stones, in shallow running water. Miss Ella Weeks, coll. 26. Wildcat creek, about two miles west of Manhattan, Riley county. 27. Crayfish are not at all common in the lower part of the Kansas river, at least near Lawrence, where I have had opportunity to observe it. The fishermen, as a rule, say there are none in the river. I have, however, seen the casts of _C. virilis_, and think it hardly probable that they could have washed in from any of the small tributaries.