166 THIRTIETH REPORT ON THE STATE MUSEUM. [54] 



Pyrameis Carye was also carnivorous, but to a very moderate 

 extent, preferring at all times fresh plant-food to flesh, while 

 others, as the Noctuidse, would not touch the plants after 

 having once tasted flesh. 



This peculiarity of the Patagonian caterpillar is easily 

 explained. During the summer, excessive heat and drought 

 prevail, and these, coupled with dry winds, tend to wither and 

 destroy all vegetation. As the caterpillar is then deprived of 

 its proper nourishment it is compelled by the law of self- 

 preservation to seek elsewhere for food, and so it comes that 

 they eat one another. This habit becomes hereditary, and the 

 descendants frequently practice it, even when there is no lack 

 of vegetable food.&quot; 



