180 COMMON BRITISH ANIMALS 



to within a few degrees of the surrounding air, and 

 its breathing becomes shallow and irregular. If 

 accurate measurements are taken it is noticed that 

 much more oxygen is absorbed than is accounted for 

 by the CO3 given out, so that the animal actually 

 gains in weight. The heart beats more slowly and 

 less forcibly, and the activity of the nervous system 

 is much reduced. On awakening from this condition 

 in the spring these phenomena are reversed. The 

 animal's temperature rises sometimes as much as 

 three degrees in fifteen minutes. The muscles 

 shudder convulsively, the heart beats more strongly, 

 and the skin, before pale, assumes a rosy blusli. 

 Respiration becomes more rapid, and there is a great 

 discharge of CO3 from the lungs.'' 



Dr. Alcock adds that " bats store their food 

 internally, and occasionally wake up and eat," 

 by which, we suppose, he means absorb or 

 assimilate the stored food. The other members of 

 the genus Vesperugo, best known to us, are the 

 serotine, the noctule or great bat, and the hairy- 

 armed bat. 



The serotine {Vesperugo serotinus), although a 

 widely distributed bat ranging from the New World 

 to the Old, is rare and local in this country. It has 

 been taken near London and at Folkestone and the 

 Isle of Wight. The head and body together measure 

 2| inches and the tail 2 inches. The fur is smoky 

 brown above and j^ellowish -white beneath. It has 

 a slow fluttering flight and only comes out late in 

 the evening. 



The noctule or great bat {Vesperugo noctula) 



