FOOD OF SUBTERRANEAN CRUSTACEA. 
BY L. S. ROSS. 
Supply of food and demand for it is one of the important factors to 
be considered in the struggle for existence, a factor that insistently d'e- 
mands proper attenfion on the part of every organism in its solution of 
the problem whether it shall exist or shall not. Many students have ob- 
served, many have killed and dissected hundreds and thousands of ani- 
mals in determining what is the character of the food supplies of var- 
ious species living in the water above ground, and on the surface of the 
earth, but not many it seems have entered seriously into the determina- 
tion of the food of those living in the waters under the earth. We have 
a sufficiently satisfactory knowledge of at least a part of the food of the 
Chinch bug the Codling moth, and the Boll worm, but we know little 
about the food of the subterranean animals. 
It is unnecessary to say that conditions in the darkness of the caverns 
and of the smaller underground cavities and channels are not favorable 
to the production of an abundant flora and that relatively only a small 
amount of fragmental vegetation may And its way into such channels from 
the surface of the ground. The original supply of animal food the plant, 
is then decidedly limited in quantity. The total food supply must come 
from the animals and plants living in the underground waters and from 
material both animal and plant that is washed in by the streams from 
the surface. In his classic publication, “The Cave Fauna of North 
America”, Packard states that he observed four or five species of fungi 
in Mammoth Cave and also that another observer, Mr. Hovey mentions a 
few fungi fr^'m the same cave. In his discussion with reference to the 
food supply Packard says: “As to the food of the aquatic Crangonyx and 
the Caecidotaea, one would suppose it would be almost wholly animal, but 
unless they devour their own j’oung it is a matter of conjecture how 
they can maintain an existence. Still more difficult is it to conjecture 
what forms the food of the young of these Crustacea since Infusoria, 
Rotifers, and Copepods are so very scarce. It goes without saying that 
there are no truly vegetable eating animals living pemanently in caves; 
no plant life exists (except in rare cases a very few fungi, and most of 
these probably carried in bj^ man) in the caves on account of the total 
lack of light.” Cope, referring to the Wyandotte cave fauna says: “As 
to the small Crustaceans little food is necessary to support their small 
economy, but even that little might be thought to be wanting, as we 
observe the clearness and limpidity of the water in which they dwell. 
Nevertheless the fact that some cave waters communicate with outside 
streams is a sufficient indication of the presence of vegetable life and 
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