SQUIRRELS 69 



attitude of complete surrender (see "Youatt on the 

 Dog," Amer. Edit., p. 34.) Even dogs would not be 

 inclined to worry a fox apparently dead. And what of 

 the feigning of the opossum ? Eomanes finds a special 

 difficulty in this subject, because, as he says : " On the 

 one hand, it is obvious that the idea of death and its 

 conscious simulation would involve abstraction of a 

 higher order than we could readily ascribe to any 

 animal, and, on the other hand, it is not easy otherwise 

 to explain the facts." 



I cannot help thinking that this difficulty is a sample 

 of those we make for ourselves by attempting to define 

 and classify where Nature has left things complex and 

 unsusceptible, of the sort of simple analysis after which 

 Eomanes and others are, in this instance, striving. 



If there is a vertebrate animal in which the feigning 

 of death is an instinct, as pure as such an instinct can 

 be, that animal is the opossum (Didelphys virginiana, 

 Shaw). If invariability of behaviour under similar 

 circumstances be essential to an instinct, then the 

 opossum's feigning is instinctive. From the account of 

 a writer in the American Naturalist (vol. vi.) we 

 learn that a Turkey Buzzard (Cathartes aura) may run 

 upon an opossum and, after flapping his wings a few 

 times over him, the opossum will go into a " spasm," 

 and the buzzard proceed to pick out its eyes, and 

 " generally take a pretty good bite from its neck and 

 shoulders." From all that I have been able to learn of 

 the behaviour of this animal in the presence of such 

 circumstances as lead to its so-called feigning, I have 

 been led to conclude that it is really largely, if not wholly, 

 a condition allied to, if not identical with, Preyer's 

 cataplexy ; but no one seems to have given the subject 

 that accurate examination necessary for a solution, 

 in this, perhaps, the very best animal in which to test 

 it. The creature is abundant, and could be captured at 



