CURCULIOS THAT ATTACK WALXTJT AND HICKORY. 7 
nuts (PL I, C), and in excavating the egg chamber in such nuts the 
female beetle takes her position on this withered part of the blossom, 
and, with her head pointing toward the nut, proceeds to excavate the 
crescent-shaped egg chamber. On account of her method of work 
the concave side of the crescent faces the tip. (PI. II, A.) It is 
not unusual to find a young butternut with a row of these crescent 
marks completely encircling the blossom end. 
As the nuts develop and the husk becomes tougher the beetle 
changes somewhat her method of procedure, and instead of cutting 
out the crescents for her eggs, places them in simple cavities gouged 
into the side of the nut through small openings in the skin. Such 
cavities are usually arranged in groups, the skin about the wounds 
being marked by dark stains from slight exudations of juice and from 
excrement voided by the beetle during the excavating process. These 
groups of punctures often contain half a dozen eggs each, one having 
been found by the writer which contained 11. 
NATURAL ENEMIES. 
During this investigation two species of dipterous parasites have 
been reared in West Virginia from larva? of the butternut curculio. 
These have been determined by Dr. J. M. Aldrich, of the United 
States National Museum, as Chaetochlorops inquilina Coq. and Cho- 
lornyia longipes Fab. Both species are rather abundant, the first- 
named, especially, rendering good service in holding the curculio in 
check. Other investigators have reared the following species from 
this host: Metadexia basalts G.-T., Cholomyia inaequipes Bigot, 
MyiopTvasia aenea Wied., and Sigalphus curculionis Fitch. 
THE BLACK-WALNUT CURCULIO. 6 
In June, 1919, the ground beneath bearing black walnut trees 
(Juglans nigra) at French Creek, W. Va., was found to be strewn 
thickly with young nuts the size of small marbles. Examination 
showed that each nut contained a single dirty-white larva half an 
inch or less in length. A quantity of the nuts were collected and 
placed in rearing jars with the expectation that in due time beetles 
of C onotrachelus juglandis would be reared therefrom. When the 
beetles appeared, however, they were slightly different from C . jug- 
landis, and specimens submitted to Mr. E. A. Schwarz, of the 
United States Department of Agriculture, were determined as C 'ono- 
trachelus retentus Say, a species the habits of which had hitherto 
been practically unknown. Further observations proved that this 
species attacks commonly the young fruits of black walnut in many 
localities in the eastern part of this country. 
6 Conotrachehis retentus Say ; suborder Rhynchopbora, family Curculionidae, tribe 
Cryptorhynchini. 
