THE COPULATORY ATTITUDES 69 



more than one of a pair is likely to be killed 

 in an attack. The male's death is nothing to 

 the species, for he probably has already ferti- 

 lised the female, if not during the last copula- 

 tion, at a former one ; her death would be 

 a great loss to the species, the loss of very 

 valuable fertilised ova. 



The length of time taken by the copula- 

 tory act varies with the species, and among 

 mammals is longest in the predatory ones ; 

 compare, in this respect, the Felidae Canidae 

 and Mustelidae with the Suidae, Cervidae 

 Equidae or Muridae and Leporidae. 



Among birds, I am aware of only one ex- 

 ception to the rule that the male mounts the 

 hen Swans (Cygnus olor), which copulate 

 breast to breast, and so will apparently be 

 equally liable to be killed if then attacked. 

 It is noteworthy, that of all birds, Swans are 

 probably the least liable to attack, because of 

 their pugnacity and great strength. 



In the majority of insects, the copulatory 

 period is often prolonged for many hours or 

 even days ; during this long period the pairs 

 are in a helpless condition, able only to make 

 feeble attempts to escape from danger. In 

 many species, the male rests on top of the 

 female, as it were guarding her and often 



