204 Transactions.—Zoology. 
The Lecanide affect the most varied forms and habits. Some are flat, 
some are globular; some are naked, some covered with a test which may be 
cottony, or glassy, or waxy; some are viviparous, some form cocoons or 
nests for their eggs. But there are two charaeters which very clearly 
distinguish them all from the Diaspide. These are the presence of a 
mentum or under lip, and an abdomen cleft at its posterior extremity, with 
two triangular lobes above the cleft. 
In the Diaspide the rostral sete are clear of the body from the moment 
they leave the tip of the rostrum. In the Lecanide the sete pass some 
little way down the body, and then, returning towards the rostrum, pass 
through a second tube, or mentum, as shown in plate VL, fig. 11a. This 
mentum is also visible in the next group, the Coccide proper; but it is there 
articulate, whereas in the Lecanids it has but one segment. 
The rostral sete appear to be generally three, but in some instances I 
ean observe that one of them is double. 
The abdominal cleft and its lobes are shown in plate VI., fig. 115. There 
are of course specific differences in the size and shape of these lobes, in the 
hairs on the abdomen, and in the spines surrounding the anal ring. 
In plate VI., fig. 11c, I give a representation of the respiratory system of 
& Lecanium, the arrangement of which does not greatly differ in the species l 
which I have observed. It will be seen that there are four stigmata, from 
each of which start large trachee covering the body with their ramifica- 
tions. Fig. 11d gives a magnified figure of a stigma, mounted in balsam, 
with the stigmatic spines. - 
The antenne in the young insect have usually six or seven joints; in 
the adult female seven or eight. The feet end in a single claw; just above 
the claw spring four hairs, of which the two uppermost are long, ending in 
a small knob, the lower pair generally shorter and broader, swelling out into 
a club at the end. See plate VI., fig. 11e. 
The males of most of the Lecanide are, I believe, unknown. 1 have 
been fortunate enough to procure specimens of males of one indigenous 
species. 
The two distinguishing characters just mentioned, the uni-articulate 
mentum and the bi-lobed abdomen, are best observed in the young insect. 
The former, indeed, is often not to be made out in the adult, but the latter 
is generally conspicuous enough to prevent mistaking one of the Lecanide 
for an insect belonging to another group. 
All the Lecanide are very much infested by a fungus, apparently of the 
order Coniomycetes. No doubt most people have observed that plants 
attacked by seale, such as for instance the holly, or the ivy, have also their 
leaves much blackened. The blackening is due to the fungus just men- 
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