222 ENTOMOLOGICAL NEWS [XXXL 220 
Notes on the Genus Hetaerius and Descriptions 
of three New Species (Coleop.) 
By J. O. Martin, Berkeley, California 
During the past five years I have spent such time as I have 
been able to spare during the proper season in collecting the 
curious ant guests belonging to the genus Hetaerius. It isa 
rather laborious form of collecting as the ant nests in which 
these beetles are found generally occur under stones, many 
of which require considerable effort to overturn.. Thus far 
in my experience, I have found them only during the winter 
months after the ground has been thoroughly wet by the 
rains. At such times the ants bring their eggs, larvae and 
pupae, as well as the Aphids they may possess, to the under 
side of the rocks to absorb the heat gathered by these stones 
on such days as the sun may be shining. Here too other 
guests may sometimes be seen and occasionally the desired 
Hetaerius. Once I found six specimens of Hetaerius zelus in 
a single day, often two and more often but one represented 
the spoils of a strenuous day’s work. Far outnumbering 
these red letter days were those in which the only reward 
was an aching back and painfully worn finger tips. 
As to the habits of these beetles I have been able to learn 
little, for during the excitement, due to the sudden flood of 
sunlight the main reaction seems to be toward escape to the 
underground galleries. Sometimes the Hetaerius may be 
found clinging to the under side of the stone, though more 
frequently he is jarred off by the over-turning process. He 
then feigns death as so many of the Histeridae do, but in a 
short time comes to life and straddles rapidly away on his 
clumsy appearing legs toward the gallery entrance. Twice 
I have seen an ant pick up the beetle and start under ground 
with him, but as a rule the Hefaerius makes off under his 
own power. 
During a recent trip to Mill Valley, Marin County, Cal- 
ifornia, I had the good fortune to take two specimens of 
Hetaerius which on examination turned out to be unde- 
