NESTING ARCHITECTURE 



ing my city manse with the church, I have noted similar 

 enclosures built around the stock at points where a 

 branch diverged therefrom. They were apparently 

 wrought out of ''carton' -that is, a combination of 

 wood-dust, loose earth, minute particles of straw, hay, 

 and horse-feed (the droppings of passing animals), such 

 as drift from the street into corners and crevices of walls 

 and upon the foliage of city plants (Fig. 23). This 

 material had been mixed into a sort of mortar and fixed 







by a natural cement secreted by the ants, until it formed 

 a woody composite that easily crumbled between the 

 fingers, but held together well enough to answer its 

 purpose as a temporary tent. Structures of a similar 

 character have been observed around the bases of the 

 needle-like leaves of pine-trees in New Jersey and else- 

 where. 



To what purpose are these rude shelters made? 

 Chiefly to obtain exclusive and undisturbed possession 

 of aphides and other insects that excrete the honey- 

 dew of which they are so fond. [\V. 9, pp. 1-18, Plate 

 ii. copied.] This enclosure not only serves to restrain 

 the insect herds from wandering to inconvenient sites, 

 but shuts out alien ants that, when strolling about, as 

 is their wont, in search of food, might happen upon 

 the pre-empted aphidian flock, and encroach thereon. 

 In short, it is the Cremastogaster's way of " staking her 

 claim." 



It is interesting to notice that this tendency to build 

 carton tents exists in this species not in full vigor as a 

 thoroughly developed and fixed habit, but as a sub- 

 sidiary tendency, a survival, it may be, of an ancestral 

 habit once strong and persistent, but which, in course 



of time, has been gradually weakened and well-nigh 



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