296 Transactions. —Zoology. 
or callosities as of some exuded substance. The skin, as shown in fig. 10, 
is covered with minute hairs interspersed irregularly with circular spin- 
nerets. The spiracles appear to be round, as in Lecanium; the traches are 
very large; there are no spiracular spines. 
The eggs, as stated above, are brick-red in colour, oval in shape ; and I 
was fortunate enough to hatch out a number of the young insects. These, 
as shown in fig. 11, have generally the shape of the adult, and are of the 
same colour. The antenna, fig. 12, have six joints, of which the last is the 
largest; on this are several strong hairs. The eyes resemble those of 
the adult; as also the legs, generally ; but these latter, fig. 18, are somewhat 
longer, and there is no fringe on the internal edge of the tibie and tarsus. 
The trochanter shows the same long hair, but instead of the bristles at the 
claw there are two long fine knobbed digitules. The rostrum and mentum 
are prominent and well defined ; the latter seems to be bi-articulate ; and 
the setz are very long and strong (I can only make out three). The skin 
is covered with circular spinnerets and minute hairs, and the spinnerets are 
most numerous at the end of the abdomen, where also are two long hairs. 
The anal orifice seems to be encircled by a folded ring. Length of the 
young insect, about =; inch. 
In the second stage of its existence the insect does not generally differ 
from its later form, but the antennz have only nine instead of eleven joints, 
and the fringe of strong hairs on the inner edge of the tibia and tarsus is 
much less developed. 
It wil be seen that the antenne follow the same gradation as in the 
genus Icerya (described by me last year), increasing from six to nine, and 
lastly to eleven joints. 
It remains to decide the affinities of this insect. I have put notes of 
interrogation at the head of this description because I cannot be quite 
certain that Colostoma is new. The whole group of the Monophlebide 
requires, I think, more investigation. Most of the species are tropical, or 
at-least, found in out-of-the-way places, and the facilities for examination 
and description have been by no means great. In one genus of the group, 
viz., Monophlebus, Y believe that the females have never been described, and, 
as I have not the male of Celostoma, I cannot distinguish it from Mono- 
phlebus, with this exception, —that I cannot find that Monophlebus is destitute 
of a rostrum. In fact, Cwlostoma possesses the characters, as far as I am ^ 
aware, of most genera of the group. The young insect resembles Calli- 
pappus; the trochanters of the adult female are like Porphyrophora ; the 
callosities of the body resemble Drosicha. But it differs from all, and 
unless itis the female of Monophlebus, i& must be a new genus; but the 
frequency of the males of Monophlebus elsewhere, and their rarity here, 
