162 KANSAS UNIVERSITY SCIENCE BULLETIN. 



SUMMARY AND CONCLUSIONS CONCERNING 



HABITS. 



Character of Localities. The character of the waters in 

 which the crayfishes occur has been sufficiently discussed under 

 the conclusions concerning distribution. 



Summary of Habits by Groups. As already suggested 

 under "Distribution," the time is not come for any generaliza- 

 tions as to the habits of the groups. The most-modified forms 

 — the blind species and the burrowing species — are not confined 

 to a single group. 



Habits During Winter. Of the habits of the crayfislies 

 during the winter little is definitely recorded. It seems most 

 probable that the stream-inhabiting species pass the winter in 

 burrows in the bank or under stones, etc., in the bed of the 

 streams. The latter is sometimes the case with C. virilis. The 

 burrowing species seem quite generally to spend the winter in 

 burrows, coming out early in the spring, and returning again 

 when the water begins to become low, as the summer progresses. 



The Blind Species. A summary is unnecessary ; the in- 

 formation at hand may be found under C. acherontis, C. setosus, 

 C. hamulatus, C. pellucidus, and C. 'pellucidus testii. 



The Burroaving Species. Some of the North American 

 forms have attracted particular attention on account of a pecul- 

 iarity in their mode of life as compared with the better-known 

 Euro|)ean species. While the interest which has been taken in 

 the burrowing forms is a perfectly natural one, it seems that in 

 some ways an entirely too difficult problem has been made of 

 .it, for the origin of the habit seems quite easy of explanation. 

 Cambarus is not the only genus of the family having representa- 

 tives which depend more or less upon this mode of life, at least 

 at certain seasons of the year, or when being in certain locali- 

 ties,-'* and the ultimate adoption of this method of life as the 

 regular one by some species is not at all difficult to conceive, 

 especially in a territory vast areas of which are habitable for 

 the typical members of the genus for a part of the year onl}^. 



28. The burrowing habits of Chemps bicarinatus have been described, and the same habit is 

 characteristic of some members of the South American genus Farnslcicus. ( See Faxon, '98, and 

 Lonnberg, '98.) In some localities Astacus is said to burrow extensively in the banks of the 

 streams. (See Huxley, '97.) 



