examining the first specimen it will be seen that it once possessed these 

 processes, as there is in the basal excavation on each side a roughened 

 or alveolate space showing the place of attachment. The uniformity of 

 surface of these spurs in connection with what is seen in the other spe< i 

 men proves conclusively that their loss is not owing to an accident. 

 These, with other questions present themselves. Are these pieces deddu- 

 ous like the horns of the Cervidae, or are they gnawed out by the ants? 

 And in the latter cast', what for? Does the same thing occur in other 

 species? Yours truly [ohn Hamilton." 



The specimen submitted to me by Mr. Rivers showed plainly an 

 inequality in the notching of the hind angles of the thorax as well as an 

 irregularity of the edges of the notch. It is my belief that the irregular- 

 ities 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 pubescens 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 reason- 

 ing insects, finding the processes in their way have deliberately removed 

 them, either partially as in the Rivers specimen, or entirely as in the other. 

 That the processes are naturally deciduous, as are the horns of the Cervidse 

 or the mandibular appendages of the Otiorhynchs is hardly supposablc 



"Mr. Schwarz has also made some observations bearnig on this point, 

 as follows: 



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. n/Ar. My attention was at once at- 

 tracted by three objects on top of the ant hill, which at first glance ap- 

 peared to be compact masses of ants. Upon looking closer to each 

 of the masses proved to consist of a living CremastocJiilus 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 in- 

 tended to prevent the escape of the Cremastochili from their colony. 

 Herein they were evidently successful, as upon waiting for a considerable 

 length of time there was no change in the situation. I then proceded to 

 investigate the interior of the ant hill, which consisted of numerous layers 

 of intricate galleries and chambers, all built of rather loose earth without 

 any sticks or other debris. Within the chambers several more Cremasto- 

 chilus were found but not attended to by ants. At this as well as at 

 previous occasions I failed to find any trace of the larva or pupa of Cre- 

 mastochilus either within or beneath the ant hill. E. A. Schwarz 



