iene no PENNE 
MasxeLu.—On some Coccidz in New Zealand. 191 
the focus of the curve (this does not hold good for all genera), and it is 
surrounded by groups of minute circular marks, arranged like bunches of 
grapes, whilst other marks are scattered singly over the abdominal region. 
These marks, which are in reality the open ends of tubes, are supposed to 
be a kind of spinnerets from which the insect builds round itself the shield 
of which I spoke just now. Some of the chief characters upon which the 
specific differences of Diaspide are founded, are the presence or absence of 
these spinnerets, the number of the groups, their continuity or separation, 
and the number of openings in each group. There are other features, such 
as difference of outline in the body, difference of shape of shield, difference 
of form of the male, difference of length in the thoracic band of the male. 
But these are often more properly generic than specific differences; more- 
over, the excessive rarity of the male insects renders it very difficult to 
arrive at certainty from them; whereas the abdominal markings of the 
females are in general so distinctly clear that they offer an excellent means 
of distinguishing between individuals. 
The mouth is, as I said above, absent entirely in the male insect in its 
perfect state. The mouth of the female consists of a rostrum, or beak, on 
the underside of the head, some little way from its anterior edge. It appears 
in the Diaspide to have no joints, and from its interior start three (or in 
some cases four) very long, thin tubular bristles, which, I suppose, the insect 
inserts into the stomata or minute orifices of the plant on which it lives, for 
the purpose of withdrawing thence its food. My plate V., figs. le and f, 
show this rostrum (which is, with modifications, common to all Coccide), as 
it appears on the insect, and as it shows after mounting for the microscope. 
So much for the general features of.the female. The male differs a 
good deal in shape in various species, but, as far as it is known, has always 
two wings, six legs terminated by a single claw, antenna usually of ten 
joints, and, at the posterior end of the abdomen a long double spike, 
sometimes nearly equal in length to the whole body. The insect undergoes 
three transformations. From the egg it emerges as an oval insect similar 
in all respects to the female; in some species it surrounds itself with a 
shield like that of the female, in others the shield is much longer and 
narrower. After a time it discards its first pellicle and remains in the 
shield, gradually changing into the pupa stage. During this process, 
according to M. Signoret, the successive formation of the eyes, wings, 
antenne, and abdominal spike may be observed. I have specimens of 
pups of Aspidiotus epidendri, in which this formation is apparent. The 
first pellicle is the only one which remains attached to the shield, as the 
insect emerges from the pupa stage, winged and perfect; consequently, in 
some species it is possible to distinguish between the shields of the two 
sexes simply from the presence in one of two pellicles, in the other of only 
one, 
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