June, i 9 o3.] WHEELER : STUDIES ON MYRMECOPHILES. 71 



Cremastochilus. He received from J. J. Rivers, of California, a speci- 

 men of C. schaumi with the posterior thoracic angles mutilated, and 

 from J. Hamilton, of Allegheny, Pa., one of C. canaliculars in a 

 similar condition. Concerning these specimens he writes as follows : 

 "It is my belief that the irregularities in the Rivers and Hamilton 

 specimens are the work of the ants, with which the specimens were 

 found and I have long held the opinion and have so published it, that 

 the pubescent depressed spaces near the front and under the hind 

 angles of most of the species, are glandular, and give a secretion 

 very palatable to the ants, and these almost reasoning insects, finding 

 the processes in their way have deliberately removed them, either 

 partially, as in the Rivers specimen, or entirely as in the other." 

 Horn also quotes from Schwarz the following interesting observation 

 on a species of Cremastochilus which was apparently living with For- 

 mica exsectoides : "In May, 1883, while on an excursion in the 

 vicinity of Washington, I came across a large ant hill constructed by 

 a species of Formica which is allied to, but not identical with, F. rufa. 

 My attention was at once attracted by three objects on top of the ant 

 hill, which at first glance appeared to be compact masses of ants. 

 Upon looking closer to each of the masses proved to consist of a liv- 

 ing Cremastochilus attended by numerous ants which held on with 

 their mandibles to the legs, the head, the sides of the thorax of the 

 beetles, in short wherever there was a chance for them to hold on. 

 That they did not intend to do any harm to the beetles was evident, 

 and it seemed to me that they intended to prevent the escape of the 

 Cremastochili from their colony. Herein they were evidently success- 

 ful, as upon waiting for a considerable length of time there was no 

 change in the situation. I then proceeded to investigate the interior 

 of the ant hill, which consisted of numerous layers of intricate gal- 

 leries and chambers, all built of rather loose earth without any sticks 

 or other debris. Within the chambers several more Cremastochili 

 were found but not attended to by ants." 



Hamilton (1888-1889), in his excellent list of myrmecophilous 

 insects, cites a number of species of Cremastochilus but without the 

 names of their hosts. Of C. canaliculars he says, that it is the most 

 abundant species at Allegheny, Pa. "It is found from April till 

 June with large black ants, perhaps of two species, inhabiting usually 

 under stones or other covering, but not infrequently throwing up 

 small mounds in old pastures and open ground. The nests under 



