Cercopid^. INSECTS. Aphiu.e. 269 
Family — CERCOPIDJi). 
In this very extensive family the antennae are three- 
jointed ; the head has two ocelli. If strange variety 
of form, in fact if the most outre and bizarre shapes, be 
the object of admiration, this family will supply ample 
material. Plate 8, fig. 15, shows the Meinbracis 
Fig. 169, Fig. 170. 
Bocydlum globulare. CEda inflata. 
foliacea, one of the group, with its curious flattened 
knife-like expansion of form. There are many fine 
and prettily-marked species. The genera Hetermotus 
Centrotus and others are full of the most strange 
forms. Fig. 169 shows a Brazilian insect named 
Bocydium globulare, with a series of pretty round 
balls, attached by a common pedicel to the thorax. 
Mr. Miers told me he found it once abundant. Some 
have curiously inflated appendages over them, quite 
concealing the rest of the insect. These, too, are Bra- 
zilian. Fig. 170 shows a marked and beautiful species 
of CEda, a very singular genus. It is named CEda 
inflata. 
We now come to Cercopidce proper. These and 
the Tettigonice, a very extensive, beautifully coloured 
set of long, rather parallel insects, abound in South 
America and in Asia. The Cercopis and the allied 
genera are largish insects, strongly and broadly marked. 
We have but one small species in this country. Our 
little species of Typhlocyha, Evacanthus, and Jassus 
are extremely beautiful little creatures. 
Of the common 'Frog-ho'g'(i&v{AphroplioraSpumaria), 
in our little town gardens, how often are we annoyed 
to see our plants infested by the larva, which carries on 
its depredations on their juices, concealed by an enve- 
lope of white froth closely resembling saliva ! The 
insect has derived its name of Frog-spittle from this 
frothy exudation, which is secreted by peculiar organs 
in the tail of the larva. This exudation protects from 
the heat of the sun the soft body of the larva, which 
but for this would soon shrivel up ; and also conceals 
it from birds and many insects which would otherwise 
prey upon it. Notwithstanding the concealment, wasps 
often get at these larv® and carry them off. Few know 
that the little broad-headed brownish-grey jumping- 
insect, so common on plants, is the frog-spittle insect 
in its perfect state. By many these insects are regarded, 
along with the Aphides, as species of the very compre- 
hensive though most unscientific genus, vulgarly called 
“ Blight.” 
Family— -PSYLLID^. 
Unlike other Homoptera, these insects and the Aph- 
ides have long antennae. They are very destructive to 
plants, diverting the sap. The box of our gardens is 
often much injured by the Psylla Buxi, while the 
Psylla Pyri, and a Chernies found on the apple, de- 
stroy the young shoots and leaves of the pear and 
apple. Many of these insects in their larva state, are 
covered with a cottony secretion. 
Leuckhart,* in his work on the ‘‘ Alternation of 
Generations,” has proved that a spontaneous evolution 
of eggs takes place in the Coccidse. He ascertained 
that all the individuals of the wingless generation of 
the genus Chernies, or Bark-lice, were of the female 
sex, and that they laid eggs capable of evolution with- 
out the intercourse of males. 
The common Fir-louse (Chermes hietis) passes the 
winter in the wingless state, in the form of a plump in- 
sect not larger than a grain of sand, under the covering 
of a woolly coat, at the base of the scaly young buds 
of the fir. Leuckhart has convinced himself that the 
reproduction of the Fir-lice takes place in both genera- 
tions by a parthenogenetic process, by the spontaneous 
development of the eggs. Leuckhart, who examined 
fully two hundred of the Chernies, never met with a 
male among them ; he has no doubt that the Fir- lice 
generally propagate without males. He leaves it unde- 
cided whether males are entirely wanting, or whether 
they merely make their appearance from time to time 
under certain favourable circumstances, and then fecun- 
date the females ; yet, he adds, “ It almost appears to 
me as if certain anatomical conditions rendered the 
first supposition to a certain extent credible.” 
Family — APHID.® {Plant-lice). 
The Aphides are perhaps the greatest enemies of 
the vegetable world, and, like the locusts, they have 
been known to swarm at times in such myriads as to 
darken the air. We might here quote from the writ- 
ings of Kaltenbach and Professor Huxley, who have 
recently paid considerable attention to their history, 
ancT" who bear out Reaumur’s assertions of the infinite 
and almost incredible powers of multiplication pos- 
sessed by these feeble-looking Plant-lice. That author 
calculates that a single Aphis may in five generations 
be the progenitor of 5,904,900,000 descendants; and 
he believes that in a single year there may be twenty 
generations. Kirby and Spence show that the Aphides 
which attack wheat, oats, and barley, seldom multiply 
so fast as to prove very injurious to these cereal plants. 
The species of Aphis which attack pulse spread so 
rapidly, and cover the plants so completely, that the 
crops of pease and beans are often greatly injured, and 
sometimes even destroyed by them. These writers 
state that this was particularly the case with the crop of 
pease in 1810. In that year the produce did little more 
than equal the seed sown, and many farmers turned 
their pigs into the fields. This failure was universal 
* See Dallas’ Translation of Paper by Leuckhart, in Annals 
of Natural History, p. 321 ; 1859. 
