MEMOIRS OF THE NATIONAL ACADEMY OP SCIENCES. 25 



of small bits of cooked meat and raw liver, crumbs of bread, etc., but, tbougb they have generally carried the morsels 

 to their jaws, after long deliberation they have, apparently, taken but a few mouthfuls, and, discarding the substances, 

 have not touched them again. The specimens of Cambarus bartoni, the eyed crawfish collected in the cave at the 

 same time, ou the contrary, are quite ready to eat aud at once seize any food offered to them. The difference in the 

 a< tions of the two species at such times is quite striking. The moment the water in its jar is disturbed the eyed spe- 

 cies reais itself up on its tail, throws out its large claws, seizes the piece of meat or bread, aud, hastily conveyiugit to 

 its month, generally holds on to the morsel until it is all eaten, though sometimes this species will take but a bite or 

 two and then drop the food, and 1 do not think it will touch the same piece again.* 



The nature of the food of the carnivorous blind beetles ( Auophthalnius) is unknown. They are 

 found running over damp sand-banks, sometimes hiding in little pits excavated under stones. 

 Having retained the general habits of their out of-door allies, it is presumed that they attack and 

 devour other living Arthropods, such as their own larvae, aud those of Adelops, besides spiders, 

 harvestmeu, and mites. At all events the food supply is scanty. As stated elsewhere, the tend- 

 ency to variation in the Anophthalmi is to diminution in size, and this depauperation is generally, 

 among insects, due to lack of sufficient food. 



The only other truly carnivorous cave animals are the harvestmeu (Phalangodes) and the 

 spiders. What the food of these animals can be, unless the young of their own kind or order, 

 must remain a matter of conjecture until further observation. But, whatever their food, it must 

 be very scanty. 



The scavengers constitute a large proportion of the cave population. Adelops Jdrtus, the scav- 

 enger beetle of Mammoth Cave, is allied to Choleva and Catops, the species of which live in fungi, 

 carrion, or in ants' nests — i. e., in dark places. At present Adelops is most abundant under loose 

 stones at Richardson's Spring, where parties have for many years taken their lunch, the remains of 

 which (bread, eggs, chicken, etc.) form a perennial pasturage for these beetles. Here also congre- 

 gate Podurans and mites, as well as an occasional Scoterpes. 



The Myriopods of caverns are not members of the carnivorous groups, but belong to those 

 families which in the upper world devour fragments of dead leaves and other vegetable d6bris, or 

 sometimes growing plants. In the caves they probably sustain life by feeding on decayed wood, 

 what little fungous growth there is to be found, and similar objects, as well as bats' dung. What- 

 ever be their food, the Pseudotremia, which is perhaps the most abundant of cave animals, is espe- 

 cially common in Wyandotte Cave. When kneeling in the beaten path one can see numbers of these 

 creatures gathered around the hardened drops of tallow which drip from the candles of tourists. 

 The food of the Hadencecus is probably like that of Ceuthophilus, which lives under stones, aud the 

 nature of whose food it? not w-dl known, unless it be decayed vegetable matter. As to the food of 

 the aquatic Crangonyx and Caecidoteea, oue would suppose it would be almost wholly animal, but 

 unless they devour their own young 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 permanently in caves; no plant life exists (except in rare cases a 

 very few fungi, aud most of those probably carried in by man) in the caves on account of the total 

 lack of light. It would seem as if the lack of food, as well as the absence of light, was one of 

 the factors concerned in the diminution in size and in the slenderness of blind cave animals as 

 compared with their lucicolous allies. 



II— THE VEGETABLE LIFE OF THE CAVES. 



The extreme dryness, as well as absence of light, is especially unfavorable to the growth of 

 plants in caves. On this point the following remarks by Mr. Hubbard are in place: 



The common fungus found in Mammoth Cave has been identified by Professor Farlo w as 1 lie old Byssua aurantiaca, 

 now known underthenameof Ozoniumauricomum'Linls:. Professor Farlo w, who kindly identified the cave plants, says 

 that it is ''found in caves on wood in Great Britain, Germany, etc., and has been found in Michigan and elsewhere 

 by Schweinitz. As far as I know it is simply the mycelium of some unknown fungus." 



I observed, in all, four or five species of fungi in Mammoth Cave ; besides the Ozonium, a 

 reddish button-shaped fungus, a green mold, a long white mold, and a fungus (Plate XVII, fig. 3) 



* Proc. Best. Soc. Nat. Hist., xviii, 16, 1875. 



