496 MEMOIRS OF THE CARNEGIE MUSEUM 
likely that many of our freshwater fishes depend largely upon crawfishes for nutri- 
ment. It would be interesting to investigate how far this mutual correlation 
between fishes and crawfishes holds good in our state. The presence of a river- 
species in our western streams, and its absence in any drainage systems in the cen- 
tral parts is very remarkable. Indeed C. bartona is found in rivers, but only occa- 
sionally, and in small numbers. My own observations are not sufficient to give an 
approximate idea as to these relations, since I did not pay much attention to the 
fish-fauna, and the latter has decidedly deteriorated, at least in quantity, and the 
fish have become rather scarce in most of our streams. Possibly the decrease in the 
number of fishes has caused an increase in the number of crawfishes. 
4. Crawfishes as obnoxious creatures. 
For the river-species hardly a point can be mentioned which would tend to show 
that they are obnoxious to human interests, except the fact that they occasion- 
ally capture young fishes. It is different with the burrowing species, which often 
become troublesome. In regions where chimney-builders are abundant I have 
repeatedly heard complaints about the chimneys, and chiefly so in the case of C. 
carolinus in Somerset County, Pennsylvania, Garrett County, Maryland, and Preston 
County, West Virginia. Here the mud-piles may hamper farming operations by 
interfering with the harvesting machines, clogging and ruining them. At Selbys- 
port, Maryland, I was told that conditions were so bad that the farmers tried to 
exterminate the crawfishes by throwing unslacked lime broadcast over the fields, 
which operation was partly successful, the crawfishes coming out of their holes by 
hundreds in a dying condition. I was told that this treatment, repeated several 
times, had considerably reduced the numbers of the red crawfish in this neighbor- 
hood. At no other place did I hear of attempts made to kill these crawfishes, 
although farmers were unanimous in denouncing them as a nuisance. 
At a few places another complaint was made, namely, that the chimney-builders 
were cutting off and eating up sprouting crops. This was affirmed with reference 
to ( carolinus at Reedsyille, Preston County, West Virginia, where a farmer told 
me that this species had cut off the largest part of a crop of buckwheat, so that 
practically nothing was harvested. At Parson, Tucker County, West Virginia, 
complaints were made that the same species had damaged sprouting corn; and at 
New Martinsville, Wetzel County, West Virginia, I heard that C. diogenes was 
charged with eating up all kinds of sprouting crops, corn and beans being especially 
named. 
I do not doubt that these complaints are justified, and that the burrowing species 
