29 
shorter and blunter. The whole aspect of these galls when fresh is 
that of a miniature seed capsule of the common Jamestown weed 
(Datura stramonium). They are of about the same green color of 
the leaves and studded with reddish brown papille. The orifice or 
mouth, at the base of the gall, is circular and 1 to 2™™" in diameter, 
with its external prolongation more or less decidedly funnel-shaped, 
terminating in a rounded or bulging rim, to allow the departing 
migrants space to adjust their wings for flight. The inner wall of the 
gall is smooth and coated with a delicate layer of a white secretion, 
to prevent the watery fluids, or honeydew, expelled by the insects from: 
adhering to the surface, as a preservative against premature decay or 
the drying up of the tissues of the galls. After attaining their full 
Fia. 14.—Hamamelistes spinosus: a, mature gall; b, section of gall—natural size (original). 
growth, they remain fresh and succulent for a long time, so as to 
enable the latest additions to their inhabitants to acquire maturity. 
The majority of these galls become dry and brown by the end of sum- 
mer, though occasionally fresh and green ones, containing the insects 
in various stages of development, may even be found as late as the 
end of November. 
Stem-mother; first stage.—The young stem-mother, after hatching, 
is extremely small and measures only about 0.2™™" in length. She is 
broadly oval and of a dark purplish-brown color; the eyes, antenne, 
and legs are blackish. The head is broadly rounded in front and 
bears two small bristles. There are three short and stout secretory 
tubercles each side of the prothorax, arranged in a triangle—two each 
