October, 1900.] 



PSYCHE. 



113 



June 2 2ncl. They are paler and rela- 

 tively somewhat narrower than the adults. 



My observations on the habits of Myr- 

 mecophila began early in March of the 

 present year. The little crickets were 

 taken from the Formica nests and placed 

 in artificial nests of Pogonomyrmex, an 

 ant of slower movements and in many 

 other respects more satisfactory for pur- 

 poses of observation than the Formica. 

 At first I used nests consisting of large- 

 mouthed glass jars containing some earth 

 in which the ants readily dug their gal- 

 leries and chambers, sometimes next to 

 the glass; but quite as often where 

 their occupants could not be seen. The 

 crickets placed on the earth at once 

 crept down into the galleries and could 

 be seen only from time to time moving 

 about unmolested among the ants and 

 along tire walls of the burrows. This 

 did not satisfy me, so I abandoned these 

 earthen nests for cement nests of the 

 Janet pattern. I had no occasion to re- 

 gret this change as it enabled me to 

 observe the insects for hours at a time 

 without disturbing them, especially in 

 the lamplight, of which both the ants 

 and the crickets seem very fond. The 

 following from my notebook is one of a 

 number of similar observations. 



April 3rd. Placed in the Pogonomyr- 

 mex nest twenty Myrmecophilas, eight 

 or ten of which had been squeezed 

 or had lost one or both saltatory legs 

 during capture. All the disabled individ- 

 uals were at once seized and dispatched 

 in so vindictive a manner, that I could 

 not doubt that the ants were irritated by 



the pungent nconijibaibis nest-odor still 

 clinging to the crickets. In an instant 

 all the ants in the compartment of the 

 nest had gathered in little groups, each 

 devouring a Myrmecophila. The un- 

 injured crickets made not the slightest 

 attempt to escape but felt themselves 

 perfectly at home as soon as they set 

 foot on the floor of the nest. Their 

 adaptation to a new nest and to an ant 

 of larger size and belonging to an entire- 

 ly different subfamily from their former 

 host, was immediate and complete. With 

 constantly vibrating antennae they be- 

 gan dodging in and out among the 

 little groups of assembled ants. From 

 time to time one of them would be seen 

 cautiously approaching an ant, that was 

 busy with its dinner of Myrmecophila, 

 and fall to nibbling at its legs or the tip 

 of its abdomen. There could be no 

 doubt that the cricket derived some ben- 

 efit from the oily secretion covering the 

 surface of the ant's body. At first the 

 ant disregarded this nibbling, which 

 probably resembles the attentions of 

 the toilet habitually received from sis- 

 ter ants, but the cricket's scraping man- 

 dibles and maxillae soon grew annoying 

 and the ant would either move away or 

 turn its head, open its mandibles and 

 make a lunge at the Myrmecophila 

 like a large dog annoyed by a puppy. 

 I!ut before the huge mandibles had 

 closed, the cricket was far away, already 

 nibbling at the abdomen of some other 

 ant. Tke cricket can get at only the 

 legs and abdomen of its host, since the 

 spreading legs prevent it from reaching 



