1890.] Entomology. 971 
were used without success, but potash, in the form of muriate and 
kainit, has proved a valuable insecticide. In the proportion of one 
ounce to one pint of water muriate of potash destroys plant-lice, 
mealy bugs, bark-lice, and thousand-legged worms (Iulus,—called by 
the author of the paper ‘‘ wire-worms,’’ a misleading term). Kainit 
gave similar results. Hairy caterpillars, beetles, and bugs are not 
affected by these substances. obacco was also shown to be of 
decided value, both as an insecticide and a fertilizer. 
TEACHING EnromMoLocy.—Professor A. J. Cook, in his presiden- 
tial address before the Entomological Club, discussed the methods of 
teaching entomology in use at the Michigan Agricultural College. 
All students are required to make drawings, and to dissect, rear, and 
collect insects. Reference collections are always within reach. The 
course of study should include botany, free-hand drawing, French, 
and German. The address was listened to with marked interest, and 
some admirable examples of drawing by Professor Cook’s students 
were exhibited. 
A Warer-Lity Morx.—Professor D. S. Kellicott described the 
life-history of Zustrotia caduca. The larva feeds upon the fruit and 
leaves of Nuphar advena. The eggs are placed on the upper side of 
floating Nuphar leaves in irregular patches of a few in number. They 
are hemisphericaly ı mm. in diameter, and with a waxy hue; the sur- 
face is beset by about thirty meridianal, nodular ridges. The young 
escapes by cutting nearly off a round lid which it lifts on a hinge. 
The larvæ mature in July, and spin delicate white silken cocoons 
upon the leaves. The imagos begin to issue after a pupal period of 
eight days. 
OVIPOSITION OF THE SacrrrARIA CurcuLio.—Dr. C. M. Weed 
reported observations showing that the Sagittaria Curculio (Listronotus 
latiusculus Boh.) deposits its eggs, largely during July, in small 
bunches, usually of between five and ten, upon the leaf and flower 
stalks of Sagittaria. After being laid they are covered with minute 
particles of the epidermis of the stalk, chewed off by the parent beetle, 
and probably fastened together by some sticky secretion. Enough 
of these particles of epidermis are placed over the eggs to make a 
conical covering 1.5 mm. in diameter at the base, and 0.7 mm. high. 
When thelarvz hatch from the small yellowish-white eggs they bore 
directly into the stem, leaving the empty egg-shells and their protec- 
tive covering stillin place. 
Ovirosırion or DkcrEs spinosus.—In describing the egg-laying 
habits of the Cerambycid beetle, Dectes spinosus, Dr. id the 
