APHIS HERDS AND ANT ASSOCIATES 



The most curious and interesting of these parasitic 

 formicaries was that of a large blue-black Formica. I 

 first found its galleries at four feet below the surface, and 

 thereafter traced them to within four inches thereof. The 

 Formicas occupied the central and eastern part of the ex- 

 cavation. The architecture was less regular than that 

 of Occidentalis, which may have been the result of 

 necessity rather than natural habit, but showed arrange- 

 ment in stories. The rooms communicated with one 

 another, and were crowded with workers, callows, and 

 grubs. The galleries and chambers were placed side 

 by side a ad in the midst of those of the Occident ant. 

 One of these, located in the heart of the nest and full of 

 larvre, was just above and flanked on each side by gran- 

 aries of Occidentalis packed with seeds. Another open- 

 ing higher up was surrounded by Occidents' rooms. 

 I have rarely seen so curious a study as that presented 

 by these interblended interiors. [McC. 5, p. 154.] 



My miner assistant might well raise the query, "Which 

 of these fellows jumped the other's claim? 7 -the Col- 

 orado vernacular for, " Who was the intruder, and who 

 the original possessor ?' : The arrangement and relative 

 positions of rooms and galleries led me to infer that 

 there had been a contemporaneous growth. The two 

 queens established their original cells in vicinity. In 

 time, mutually expanding their bounds, they approached 

 each other, and thenceforward held the ground together. 

 By what peculiar gift or condition were the two species 

 able to so guide their engineering that they never con- 

 flicted? Or, did they conflict? 



I could find no traces of intercrossing of openings 

 or impinging of chamber walls. Closely as these ap- 

 proached, they seemed to be structurally distinct. What 



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