CRAYFISHES. 379 



Illinois, Michigan, Wisconsin, Minnesota, Iowa, Missouri, Kansas and Nebraska, 

 into Colorado and Wyoming.' To the eastward of Lorain County, Ohio, it 

 has hitherto been recorded from onh' two localities, both in the state of New 

 York: in 1891 Mr. Gerrit Smith Miller, Jr., brought me three specimens which he 

 found in July of that year in a small stream flowing into Oneida Lake; these were 

 recorded by me in 1898 (Proc. U. S. Nat. Mus., 20, p. u54) ; in 190G Dr. Ortmann 

 (Mem. Carnegie Mus., 2, p. 467) called attention to specimens in the New Y^ork 

 State Museum which had been taken by Mr. F. C. Paulmier in Rensselaer Lake, 

 Rensselaer Co., N. Y. I can now add to the New York stations for this 

 species the following: — pond near the mouth of Cattaraugus Creek, and Silver 

 Creek, Chautauqua Co. (U. S. N. M. Nos. 22,417, 22,408) ; Fish Creek, Buffalo, 

 Erie Co. (U. S. N. M. No. 22,418) ; and Stony Island, at the eastern end of 

 Lake Ontario, Jefferson Co. (U. S. N. M. No. 22,409). 



My first knowledge of this species as an inhabitant of Massachusetts was 

 obtained when I was walking across the mud-flats at the upper end of Pontoosuc 

 Lake on the 11th of November, 1899. The numerous mud-towers or "chim- 

 neys" here rising above the level of the flat at once betrayed the abode of 

 some kind of burrowing crayfish. Although the soil was then frozen so as to 

 make exploration difficult, I satisfied myself that the builders of the little mud- 

 towers had withdrawn to their brumal retreats in the deeper waters of the Lake, 

 leaving behind them onlj^ one dead companion, a first-form male C. immunis 

 spinirostris (M. C. Z. No. (3,687). Here the matter rested until, during a visit 

 to Berkshire in 1911, I ascertained that tliis crayfish was abundant on the 

 12th of August among the water-weeds at the head of Pontoosuc Lake. Two 

 days later I searched for it at the northern end of Onota Lake in Pittsfield and 

 again found it in altogether similar surroundings, albeit in much smaller num- 

 bers than in the neighbouring Pontoosuc or Lanesborough Pond. 



On the 15th of June, 1912, I again collected this crayfish at the outlet of 

 Goodi'ich's Pond and in the Housatonic River just above Pomeroy's Mills, 

 in Pittsfield. 



These specimens from Berkshire Co., Mass., agree in most respects with 

 the types of C. immunis spinirostris, which were collected in Obion County, 

 Tennessee. The rostrum in the Massachusetts examples tapers a little more 

 between the base and the ante-apical teeth and, the antennal scales are a little 

 shorter in proportion to the length of the rostrum. Compared with the typical 



1 Tliere are two .spepinipns of C. imtnunis, a^ f. II. and 9 , in tlic U. .S. Xational Museum, Xo. 3,257, 

 labelled as eoming from Orizaba, Mexico, througli Professor Sumichrast. 



