94 
Psyche 
[June-Sept. 
ON THE SYNONYMY OF ORUSSUS SAY 1 1 
WESTWOOD 1 
By Harry D. Pratt 
Specimens of the genus Orussus Latr. are comparatively 
rare in most insect collections. Therefore it was with some 
surprise that the author discovered on June 25, 1935, near 
his summer home in Jacksonville, Vermont, a dead sugar 
maple ( Acer saccharum) with at least twenty specimens of 
Orussus on it. Orussus has the habit of jumping, almost like 
a Haltica, before flying and then returns often almost to 
exactly the same spot from which it flew. Collection is most 
easily made by covering them with a wide-mouth cyanide 
jar, since they frequently fly out under the side of a net if it 
is snapped against the side of the tree. Subsequent collect- 
ing in 1936 and 1937 has shown that O. sayii Westwood 
emerges as early as May 31 in 1936, while 0. terminalis 
Newman persists at least until mid-July. 
If Mr. H. E. Burke’s article (Proc. Ent. Soc. Wash., 1917, 
vol. 19: pages 87-88) is correct, and “Oryssus is Parasitic” 
on Buprestidae, then the host is likely to be a species of 
Dicerca, probably divaricata Say, since what appears to be 
this species occurs commonly in the same tree. 
Careful examination and dissection of 0. sayii showed that 
this species occurred only in the male sex, while 0 . termi- 
nalis occurred only in the female. This fact in itself would 
make one suspicious as to the synonymy of the two, and be- 
comes all the more interesting from a biological viewpoint, 
since it is a well-known fact that in parasitic Hymenoptera 
the males usually emerge before the females, the reason 
apparently being that they can mate with the larger females 
as the latter emerge, while they are still somewhat teneral 
and unable to resist the advances of the male. As mentioned 
earlier, 0 . sayii emerges before 0 . terminalis , usually a week 
iContribution from the Entomological Laboratory of Massachusetts 
State College, Amherst, Mass. 
