184 Psyche ’ [December 
convex, arranged in a broad triangle. Antenne short and stout, the funiculus 
extending barely to occipital border; pedicel slightly longer than thick; funicular 
joints subequal, cylindrical, one and one-third times as long as broad; apical joint 
conical, one and one-half times the length of penultimate. Thorax trilobed, lobes 
convex. Scutellum rounded behind, with a strong transverse impression before 
the posterior border. Metanotum abruptly sloping, with strong lateral sulci. 
Petiole from side more than twice as long as thick. 
Head shining, finely densely punctuate, the temples finely shagreened; 
flagellum coarsely punctate and opaque. Thorax and petiole coarsely, densely, 
rugosely punctate; parapsides finely, transversely aciculate; gaster smooth and 
shining. Scape brown at base, flagellum black, tips of femora, the tibize and tarsi 
ferruginous; rest of body metallic green. Wings slightly infuscated, veins and 
the distinct stigma brown. 
Male: Similar to the female. The thorax is bronze in color, and the petiole 
proportionally thicker. 
One male and two females, together with numerous pupze were 
found at San Miguel in nests of Pheidole vasleti var. acohlma. 
The pup were lying among the brood of the ants, and were 
always quickly removed by the worker ants when the nest was 
uncovered. 
This species is much larger than O. occidentalis Ashmead, from 
Southern California, but is otherwise very similar. O. stramineipes 
Cameron, from Panama differs in the form of the metanotum 
which has: ‘‘a central area bordered by keels which sharply con- 
verge at the top.” This is entirely different to the structure of 
the metanotum in folteca. 
THE BACTERIAL DISEASES OF CATERPILLARS! 
By R. W. GuaseEr. 
There seems to be a considerable amount of collateral evidence 
that caterpillars are subject to bacterial diseases, but I am not 
familiar with a single case where this has been conclusively proved. 
Such a state of affairs can be explained in part by the fact that 
much of the work on caterpillar diseases was done before the intro- 
duction of Koch’s technical methods in 1880 or shortly after, be- 
fore these methods had been fully perfected. Within compara- 
1 Contribution from the Bureau of Entcmology in coéperation with the Bussey Institution 
of Harvard University. (Bussey Institution, No. 83.) 
