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MEMOIRS OF THE NATIONAL ACADEMY OF SCIENCES. 9 
7° Reaumur or 47°.8 Falir. That of Mammoth Cave is a little higher; whether the mean temperature 
of Caruiola is a little lower than that of Kentucky, we have not the means of stating. 
“ Before proceeding further, it may be well to speak of the temperature of Mammoth Cave. It 
has been roughly estimated that 12,000,000 cubic yards of limestone have been displaced by this 
immense excavation; and the importance occurred to me of ascertaining exactly the temperature of 
such a body of subterraneous air. On inquiry I learned that this had never been accurately done. 
Hence I made a series of observations in 1878, that satisfied me of the need of still more careful 
work. Accordingly, in 1881, armed with two standard thermometers, one a Casella from the Kew 
Observatory, England, and the other a Green from the Winchester Observatory at New Haven, 
Connecticut, I took a number of observations with the utmost care. Among my conclusions were 
the following: That the highest degree reached at any time in any part of Mammoth Cave is 56° 
Fahr., and the lowest 52^° Fahr.; the mean for summer being 54°, and for winter 53°. The latter 
is probably the temperature of the earth’s crust in the region where this cave is located. 
“The above conclusions are confirmed by the readings of an ordinary thermometer placed by 
Mr. Klett in the Rotunda, and left there till it was, so to speak, acclimated. This gentleman 
reports, as the result of almost daily inspection by himself or the guides, that during the period 
of six months the mercury did not rise above 54* * nor fall below 53° Fahr., the fair inference being 
that there was not at any time a variation of more than one degree! ”* 
FAUNA OF MAMMOTH CAVE. 
Infusoria: 
Vibrio and still more minute bacterium-like organisms in tightly-corked water from Mammoth Cave, 
opened at Salem, Massachusetts, 1874. „ 
Chilomonas emarginata Ehr. River Styx (Tellkampf). 
Chilodon cueullus Ehr. ? 
Syneda ulva Ehr. 
Monas 2 sp. Serena’s Bower (Tellkampf). 
Colpodat . Wandering Willie’s Spring. 
Nassula ? or Prorodon ? . Wandering Willie’s Spring. 
Bodo. Serena’s Bower (Tellkampf). 
Vermes : 
Dendrocoelum perccecum Pack. In Shaler’s Brook, Richardson’s Spring, and other pools. 
A nematoid worm, parasitic in the larva of Adelops hirtus. (Hubbard.) 
chambers very far removed from the entrance, where thick darkness reigns throughout the day, winter and summer 
alike, averages 47°.8 E., and is influenced neither by the time of year nor the time of day. To this is due the fact that 
iu the deepest caves the small number of Arthropods inhabiting them do not hibernate, and that many species belong¬ 
ing to the middle cave regions are found in the innermost parts of the caves (Anophthalmns, Adelops, Thysanura, 
etc'.). The Arthropods native to the outer regions of the caves (such as species of Sphodrus, Homalota, Quedius, 
Thysanura, Scolopendr®, etc.), like their out-of-door relatives, hibernate at the beginning of cold weather under 
sticks and stones, in moss, etc. 
* As this is a matter that has been under dispute, former observations by scientific observers having agreed on 59° 
Fahr. as the correct temperature, I give below a table of my main observations, which were most carefully made 
with practically perfect instruments on the 13th and 15th days of August, 1881: 
Deg. Fair. 
At the hotel on the hill the mercury indicated.... 92 
At the mouth of the cave (at noon). 65-J 
At the mouth of the cave (7 p. m.). 60 
At the Iron Gate, 100 yards within, where the cur¬ 
rent is strongest. 52J 
In the Rotunda (1,000 yards within). 53 
In Audubon’s Avenue. 54 
In Little Bat Avenue. 54 
In the Gothic Avenue (oldest and driest portion).. 56 
In Richardson’s Spring (in the water).. 54 
In the Arched Way... 54^ 
Deg. Fahr 
At the Bottomless Pit: 
Top. 54 
Midway. 56 
At the bottom. 53 
In the Mammoth Dome: 
Top, 250 feet above bottom... 54 
Midway.-.. 53 J 
Bottom. 53 
At the Echo River: 
In the water. 55 
In the air. 56 
Where it empties into Green River . 58 
