416 MEMOIRS OF THE CARNEGIE MUSEUM 



Since tliose parts of the stream which are inliabited by C. hiuioiii rohHsfits are 

 always well supplied with water, tliis form does not need to make extensive bur- 

 rows, and I have never observed regular ehinnieys.''- 



The ecological conditions under which ('. Ixnioiii occurs were to some extent 

 previously known. Goodman (1833 (1842), p. 293) gives a good account of them'*' 

 as observed in small sti-eams near Philadelphia. According to Abbott ( 1873) it is 

 found near Trenton, N. J., burrowing in the muddy baidvs of ditches and sn)all 

 streams, rarel}^ of the river (Delaware). This, however, is nc^t the usual condition, 

 as we have seen al)0ve. Faxon (188^)(^, j). 63) says that it prefers cooler waters of 

 mountain regions or uplands, living under the stones in clear streams and in 

 springs, which is the usual condition under which it is found in this state. How- 

 ever, that there are variations in its habitat, occasioned by exceptional conditions, 

 is seen from the case mentioned above from the state of Ohio, from Abbott's account, 

 and from the observations of Dr. J. Sloan as reported by Faxon (/. c), according to 

 which, in southern Indiana, it is found in ponds and still water, not in running 

 streams. This is, however, not always the case in Indiana, since, according to Hay 

 (1896, p. 489) it is found in "springs and streams of clear ruiuiing water, where it 

 hides under stones or dies short burrows into the Ijanks." 



3. The Burnnvhig Species. 

 Cantharus caroliitas, Qmiharus nujiunujalcnsls, Cdnihanis dloyenes. 



a. General habitat. 

 The burrowing species are always found at a certain distance from oi)en water, 

 although often in close proximity to streams, ditches, or ponds; l)ut never, under 

 normal conditions, in them. Exceptions are very rare, and only accidental, and 

 found chietl}' in the case of young individuals which have not settled down ])erma- 

 nently, or of individuals which have been disturbed.^'' These species, however, 

 always depend on the presence of water, but it is the groundwater which is inhabited 



'^Slnifeldt (1896, p. 27) figures a chimney of C. hmtiini rvhnsliis from Dear Wasliiugton, D. C. Why Shufeldt attrib- 

 utes this chimney to this form, I do not understand. He says that he studied burrows near Wasliington, " many of 

 these were of C. diogfurs, others were of C. barloni rubiislus, wliich I found abundant in Montgomery County, Md." 

 The specimen which built tlie chimney figured was not taken by Shufeldt, and he says that in the vicinity anotlier bur- 

 row was opened which contained a C. (liogitim. According to the description of the hole belonging to the chimney, it is 

 too deep and complex to belong to C. bditmii, and I do not see any reason for not regarding it as belonging to C. diiigenes. 



'^The crawfish hole, eight to ten inches deep, with a wider chamber at the end, under stones in a small stream, 

 with the opening in the water, undoubtedly belongs to this species. 



"A case where young specimens of C. iliugenes were found in numbers in open water by Dr. D. A. Atkinson will lie 

 discussed below. (See V. ) This case is also to he regarded as exceptional. 



