60 PHILOSOPHY OF 2J00L0GY. 



weight in proportion to the number of times in which they 

 revive during the term of their lethargy. 



Dr Monro kept a hedgehog from the month of Novem- 

 ber (1764) to the month of IVIarch (1765), which lost in 

 the interval a considerable portion of its weight. On the 

 25th of December, it weighed 13 ounces and 3 drams, 

 on the 6th of February, 11 ounces and 7 drams, and on 

 the 8th of March, 11 ounces and 3 drams. He observed a 

 small quantity of feculent matter and urine among the hay, 

 although it neither ate nor drank during that period. In 

 this experiment there was a daily loss of 13 grains. Ac- 

 cording to Mr Cornish, both bats and dormice lose from 

 five to seven grains in weight during a fortnight's hyber- 

 nation. 



Dr Reeves endeavoured to account for the lean state of 

 the marmot when found in the spring, as occasioned by 

 another cause than the slow but uniform exertions of the 

 vital principle. " I have (he says) been repeatedly assur- 

 ed, by men who hunt for these animals in winter, that they 

 are always fovmd fat in their holes on the mountains of 

 Switzerland, and it is only when they come out of their 

 hiding places before provisions are ready for them, or if a 

 sharp frost should occur after some warm weather, that 

 they become emaciated and weak *." This testimony may 

 be received as explaining the emaciated appearance of some 

 marmots, but does not in the smallest degree invalidate the 

 general conclusion, that all torpid animals sustain a loss of 

 weight during the continuance of their lethargy. 



From the experiments which we have already quoted, it 

 must appear obvious, that respiration is in general carried 



" " Essay on the Torpidity of Animals," by Henry Reete, M. D, 1809, 

 p* 28, 



