290 
Psyche 
[September-December 
C. armatus has fed on the larvae and pupae of the carpenter ant, 
Camponotus sp. in the laboratory (J. T. Doyen, pers. comm.). The 
larvae and pupae of other species of non-host Formica sp. have 
also been consumed. This lack of specificity may account for those 
species of ants that serve as alternate hosts, and for the wide dis- 
tribution of armatus. 
Trichomes 
Holldobler (1971) has shown that myrmecophiles have the ability 
to communicate in the same chemical language as their hosts. Tri- 
chomes are tufts of hairs that serve to increase the ability of well- 
integrated ant guests to communicate chemically. They are located 
on the ventral surface of highly modified anterior and posterior pro- 
notal projections of Cremastocheilus adults. The pronotal projec- 
tions have been cited as being modified to fit the mandibles of ants, 
and to contain glands which emit a stimulating and attracting odor 
(Wheeler, 1908). It has been proposed that these beetles are brought 
into the nest and held captive by the ants because of this odor (Cazier 
and Mortenson, 1965). 
The role of trichomes in the relationship of C . armatus to its host, 
F. obscuripes, is unknown. The ants do not appear to be specifically 
attracted to trichome areas nor are the beetles held captive by the 
ants. C. armatus is usually found unattended by ants within the 
nest, and is attacked by ants when on the nest surface. 
Acknowledgements 
The writers extend their appreciation to J. T. Doyen and J. A. 
Chemsak, U. C. Berkeley for their valuable field and laboratory 
data. J. T. Doyen also provided data concerm’ng predation on 
Camponotus sp. larvae and pupae, including the suggestion that body 
fluid was being pumped from the prey. H. F. Howden, Carleton 
Univ., Canada identified the Cremastocheilus , and D. R. Smith, 
U. S. N. M. identified the ants. We also thank Terri Alpert and' 
Don Frechin for their help in collecting field data. 
Literature Cited 
Blum, M. S., R. M. Crewe, and J. M. Pasteels 
1971. Defensive secretion of Lomechusa strumosa, a myrmecophilous 
beetle. Ann. Entom. Soc. Amer. 64(4): 975-976. 
Cazier, M. A. and M. Statham 
1962. The behavior and habits of the myrmecophilous scarab Crema- 
stocheilus stathamae Cazier, with notes on other species. J. New- 
York Entom. Soc. 70: 125-149. 
