OF PERIODIC PHENOMENA. 



341 



MAMMALS. 



With respect to these should be noted 



The times of first appearance and withdrawal of those species 

 which, like the bat tribe, conceal themselves during 

 winter. 

 of commencing and waking from winter sleep, in the 



dormouse, badger, &c. 

 of assuming spring and winter dress, in the case of 



the Mustelidoe. 



of coupling and parturition. 

 of shedding the antlers, in the stag and deer. 



In respect 

 of migration. 



In respect of 

 song. 



In respect of 

 breeding. 



BIRDS. 



Times of first appearance and disappearance* of 



regular summer and winter migrants. 

 of double passage, in those species which 



occur twice in the year. 



of appearance of rare or accidental visit- 

 ants. 



of commencing song. 

 of full song ceasing. 

 of re-assuming song, in those species 

 which are heard again in the autumn. 

 of pairing and building. 

 of laying, and commencing incubation. 

 of hatching. 



of fledged young quitting the nest. 

 The times of moulting, whether single or double. 



of collecting in flocks, and dispersing of the same in 

 spring. 



* The exact period of departure is with difficulty ascertained 

 in the case of many species ; but it sbould be especially attended 

 to in that of the swallow tribe, in which it may be readily 

 observed. 



