DESCRIPTIONS OF NEW PHILIPPINE WASPS OF THE 
SUBFAMILY PSENINAD 
By S. A. ROHWER 
Forest Insects, Bureau of Entomology, Washington, D. C. 
The present paper is based on material in the collection of 
the United States National Museum, and on that forwarded to 
the author by C. F. Baker from Los Bajfios, Philippine Islands. 
The types of all the new species and most of the specimens are 
in the National Museum. 
Genus DIODONTUS Curtis 
The scope of the genus Diodontus is here enlarged to include 
Species which belong to the group Psenulus Kohl and new 
species which differ in both thoracic and venational characters 
from typical members of the genus. Many of the species from 
the Philippine Islands differ from typical members of the genus 
in having the first recurrent interstitial with or antefurcal 
to the first intercubitus. One of the new species, Diodontus 
scutatus, differs from all other members of the genus known 
te the author, in having the parapsidal furrows strong and 
complete. At first sight these two groups seem to be worthy 
of generic rank, but there is some variation in the position 
occupied by the first recurrent, and in some species the parapsidal 
furrows are present anteriorly. For this reason, and because 
it seems likely that more collecting, in this and other tropical 
regions, will reveal still other specific aggregates showing 
diversity in structure, it has been deemed advisable to enlarge, 
rather than restrict, the generic, concept. By this, however, the 
author does not wish to be understood that he would imply that 
the Philippine species are closely allied to the Nearctic species. 
It is his belief that future investigations will demonstrate the 
desirability of naming, at least as subgenera, such specific 
groups.' 
"For a discussion of the genotype of Diodontus see Proc. U. S. Nat. Mus. 
49 (1915) 243. 
809 
