12 
long and slender, with its basal section bulbous. Before attaining 
maturity the young stem-mothers cast three skins, which are usually 
crowded into the opening of the gall, each stage lasting about a week, 
the last skin being cast between the 15th and 20th of May. 
Stem-mother, second stage (Fig. 3).—The young stem-mother, after 
having cast her first skin, measures between 0.4 and 0.6"™™" in length, 
and has become much stouter and of a broadly oval shape. She is 
dark purplish or almost black, with antennez and legs paler; she is 
slightly pruinose and provided each side of the abdomen with a brush 
of white and glistening secretion, which grows gradually longer as 
she advances in age, though lacking entirely the characteristic glassy 
rods on the back and sides of the young larve. The antenne are 
still of about the same length as in the first stage, though the third 
joint is either of a uniform thickness or slightly stoutest at base and 
without any annulations. The rostrum has become much shorter and 
stouter and reaches barely to the median 
coxe. The digitules of the tarsi and the 
bristles of the posterior tibiz and tarsi have 
become much shorter and finer, while the 
digitules have become simple. All secretory 
tubereles or pores have disappeared, except 
three or four at each side of the abdomen, 
which, however, are less prominent than in 
the young larva, and become entirely obsolete 
in the cast skin. 
Stem-mother, third stage.—After casting a 
Oe en Pee second skin she measures from 0.7 to 1" in 
dis: Second stage of stem- length. She is again stouter than before 
ae ee Geers and contains already a number of partly 
developed embryos. She is dark purplish or 
brownish and is covered with a mealy secretion, giving her a pruinous 
appearance. There are now also apparently six or seven rows of 
more or less confluent tufts of a white and glistening, straight, and 
evenly shorn secretion each side of the dorsum, directed toward the 
median line. The antennz and legs are very similar to those of 
the previous stage, except that the third antennal joint has become 
stouter at base and more distinctly tapering. The digitules, espe- 
cially those of the posterior tarsi, are longer and stouter, though 
apparently simple, and the bristles of the posterior tibiee and tarsi 
more prominent. Otherwise they are very similar to the larve of the 
second stage. 
Adult stem-mother, fourth stage (Fig. 4).—About the middle of 
May the young stem-mother casts her third or last skin, and soon 
alter having matured proceeds to produce her progeny and continues 
to do so during the following three or four weeks, or till about the 
middle of June, until her stock of larvee is exhausted, depositing from 
