winged adults of both sexes whose adult life is short. 
The more solid and usually more conspicuous autumnal galls on oak, maturing 
and dropping just before or with the leaves, contain at that time when they are 
usually gathered a scarcely visible larval cavity in a thick translucent nutritive 
layer which is used up slowly during the winter. Such galls must be kept under 
more or less natural conditions out-of-doors in some sort of breeding cage. 
Select a shady spot in the woods or under shrubs in the garden where there is a 
deep layer of leaf mold safe from molestation and from fire. Mice and squirrels 
are apt to destroy collections unless some sort of wire cage is used. A con¬ 
venient one can be made from a square or oblong piece of fine-mesh copper screen¬ 
ing. Fold over a half inch at each end. Roll into a cylinder and solder the 
long seam. A cork in each end completes a cage. It should be made in several 
sizes. The label inside should give locality, date and host on durable paper in 
waterproof ink, then dipped in melted paraffin or better,, enclosed in a well- 
corked 7 by 25 ram. vial. The year of collection should not be omitted in the 
date. Two winters often pass before any adults emerge and then some may emerge 
each spring for several years. Larvae transform in the fall before they emerge 
and remain in the gall as adults during the winter to come out when conditions 
are suitable in the spring. Adults from galls of this type are all agamic 
females and comparatively long-lived often surviving for a month in captivity. 
Many species emerge normally in late fall, for example all the species of the 
genua Disholcaspis (whose galls on twigs are in general bullet-like, detachable 
but not deciduous). The adults are all agamic females. Such galls indoors often 
become so dry and hard the adults are not able to chew their way out and it is 
better to out them out. In this case let them crawl about in a muslin-covered 
bottle for a few days until the body wall takes on its normal coloration instead 
of killing them at once. Some woody stem swellings on oak soon become so hard 
the flies have to be cut out. If very old twigs containing dead adults are 
soaked in water over night the adults can be out out with less danger of damage 
and the wings can be straightened out on a slide and left to dry before mounting. 
88 
