151 
During this time they have gradually lost their ambulatory powers, 
and remain stationary upon their victims. In the mean time changes 
equally wonderful have been going on within the abdomen. 
Eggs are continually forming, and within these the young mites 
are as continually developing, passing through their entire metamor- 
phosis, which includes the acquisition of the fourth pair of legs, (an 
exceptional character among mites) within the abdomen of the 
mother, from which they make their way as fast as they reach 
maturity. 
The females are quite prolific. I have counted frequently from 
forty to fifty young and eggs within the abdomen, and believe that 
they produce even more. The mothers survive the birth of a large 
number, if not a majority of the young. The male I have never 
found, and I am inclined to beleve with Mr. Newport, that the 
species is parthenogenous. The minute size of these young mites 
admits of their free access to the larve of the moth, through the 
very small opening where this made its entry, and a single mite 
with its progeny would be sufficient to destroy it. 
That this is very often the manner of attack is proved by the 
fact that grains in which the larve is badly infested frequently have 
no other break in the hull by which even a young mite could gain 
admission. Like the larve on which they subsist, their development 
is retarded or incteased by the temperature, they being quite active 
at a temperature of 60° Fah; but in colder weather able to remain 
within the abdomen of the parent for months in a dormant state, 
awaiting a rising temperature. 
Pteromalus gelechia, n.s. While examining the grain containing 
these larve, I frequently found pupe of a small hymenopterous 
parasite, and bred them in considerable numbers. 
I at first thought these parasites might be Pteromalus calandre, 
Howard, but Mr. Howard has pronounced it a distinct species, and 
undescribed. 
Mr. Richard Owen, of New Harmony, Ind., in ‘The Cultivator” 
for November, 1846, is said to figure a parasite which Dr. Harris 
thought might belong to the genus Pteromalus, but as I can find no 
record of any description having been published in this country, I 
shall describe it as follows: 
Male.—Length of body, 2mm; expanse of wings, 3.8mm; width 
of fore wing, 0.6mm. Head. large, broader than thorax. Antenne 
sh¢htly clavate, moderately pilose, shorter than thorax; second joint 
larger than first; fifth joimt more slender than sixth, but broader 
than fourth, and as long as both ring-joints together. Thorax 
longer than broad; parapsidal furrows distinct; the middle femora 
have a long slender spine on inner side near apex. Abdomen 
cordate, sessile, robust, and obtusely triangular. Head, face, and 
dorsum -of thorax coarsely cribrato-punctate, with scattered, fine 
hairs. Abdomen smooth, shining. Color: head and thorax steel- 
blue; abdomen black at tip; antenne fuscous throughout; femora 
of anterior and middle pair of legs scarcely darker than tibie; the 
