142 
THE PLUM CUECULIO. 
rapidly, tapping the plum. After an instant of greater excitement 
she suddenly stopped, with body raised, holding the antennae straight 
and rigid before her. The slender ovipositor was quickly inserted, 
the tip of abdomen being bent cephalad for the purpose. Oviposition 
occurred within 30 seconds. In removing the ovipositor the antennae 
were lowered partly beneath the fore-body, evidently as a help, and 
the abdomen quickly arched. 
(Sigalphus) Triaspis curculionis Fitch. 
The Sigalphus parasite of the curculio (fig. 26) was first discovered 
by Dr. Fitch, and a description with' figure of the female published 
in the Country Gentleman for October, 1859 (p. 221), and also in the 
Albany Cultivator in October of the same year. A more extended 
account is given in his address "On the curculio and black knot on 
plum trees," delivered before the New York Agricultural Society in 
1860. The specimens upon which the description was based came 
from D. W. Beadle, St. 
I 
Catherines, Ontario, and 
had been reared by him 
from black knot on plum 
trees which were infested 
with curculio larva 3 , the 
adult curculios appearing 
in numbers in the rearing 
jars. The fact that the 
black knot is also infested 
by the larvae of other in- 
sects, especially that of 
the so-called plum moth 
(Enarmonia prunivora Walsh), casts doubt on the exact host relations 
of the Sigalphus. In fact, Walsh in his report as acting entomologist 
of Illinois ridiculed the idea that the Sigalphus was a parasite of the 
curculio, and this doubt was not removed until 1870, when Dr. Riley 
reared the insect in large numbers from curculio larvae placed in jars 
in carefully sifted earth. 
Little has been added to our knowledge of this insect since the 
observations by Riley. Prof. Gillette, in Iowa Station Bulletin 9, 
page 378, gives some interesting notes on the insect; he found it 
quite common in the vicinity of Ames during the summer of 1889. 
The variety rufus Riley, later mentioned, was four times as abundant 
as the true curculionis. The substance of the same article was also 
published in the Canadian Entomologist, volume 22, page 114 (1890). 
The Sigalphus has been reared by Fayville and Parrot, in Kansas, 
from larvae of the potato stalk weevil, Trichobaris trinotata Say 
(Kansas Station Bulletin 82, p. 12), and the parasite is recorded 
from the same host by Dr. Chittenden (Bui. 33, n. s., Bur. Ent., 
Fig. 26.— (Sigalphus) Triaspis curculionis. an important parasite 
of the plum curculio: a, Male; 6, female; c, antenna. (After 
Riley.) 
