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THE LANTERN-FLIES . 
appears like a spear-head deeply notched along both edges ; but on a closer examination it is 
seen that this apparently single instrument is composed of three pieces, namely, two saw-edged 
blades, set back to back, and a central support in which they both slide. There seems little 
doubt that these instruments work alternately, like the saws of the tenthredo. 
The slits made by these curious saws are wonderfully deep, considering the instruments 
with which they are cut, and look as if little splinters of wood had been partially detached 
by a pen-knife, but left adherent at one end. Each of the burrows under these elevations 
is about a third of an inch in length, and contains from four to ten eggs. Altogether, each 
female deposits between six and seven hundred eggs. As soon as the young are hatched, 
they emerge from the cell, and make their way to the ground. At this period of their 
existence they are not unlike the common flea, both in size and shape. They grow rapidly, 
and when they are changed to the pupal form exhibit but little alteration in form, except 
that the rudimentary wings are visible externally. They live for some time in the preliminary 
stages, and guard themselves against the frosts of winter by burrowing into the ground to a 
depth of nearly a yard. When the perfect insect makes its escape, it leaves the empty pupal 
shell nearly entire, except a slit along the back through which the creature has passed. 
The male Cicada has the power of producing a shrill and ear-piercing sound, so loud 
in many species that it can be heard at a considerable distance, and becomes a positive 
annoyance, like the same tune played for several hours without intermission. The organ by 
which the sound is produced is internal, but its position may be seen externally by looking at 
the under side of the body, just behind the last pair of legs, where a pair of horny plates may 
be seen. These plates are the protecting covers of the sound-producing apparatus, which 
consists of two drum-like membranes and a set of powerful muscles. The color of the perfect 
insect is mostly of a yellowish cast, and the wings are firm, shining, and membranous, some- 
what resembling those of the dragon-fly in texture, but having larger cells or spaces between 
the nervures. 
One species of Cicada is a native of Europe ( Cicada anglica). Generally, however, the 
Cicadse are tropical insects, or, at all events, inhabit the warm countries, those in the cooler 
parts of the world being comparatively small. Several species of Cicada are eaten like the locusts. 
The wonderful Lantern-flies are known by the three- jointed antennae and the two ocelli 
beneath the eyes. 
It may here be remarked that the eyes of insects are of two-fold character, namely, the 
compound and the simple, the former being constructed of a variable number of facets, so 
arranged, that each, though a separate eye, with its own optic nerve, is made to coincide with 
the others, and to produce a single image in the sensorium. Many insects, especially those 
which fly or run rapidly, have a vast number of facets in the compound eye, the common 
peacock butterfly possessing about thirty-four thousand of these lenses, seventeen thousand 
on each side. The average number, however, is about six or eight thousand. The ocelli, or 
simple eyes, are round, lens-like objects, mostly set in front of the head ; and it is imagined 
that the two sets of eyes perform distinct offices, the compound eyes for the purpose of 
observing distant objects, and the ocelli in order to examine the food or any substance within 
close proximity. 
In many of the Fulgoridee, the head is formed into the oddest imaginable shapes, some- 
times lengthened into a curved horn, like that of the Lantern-fly, sometimes broad, with a deep 
keel above, and sometimes with a raised edge of knife-like sharpness. The head is said to 
emit a phosphorescent light, similar to that of the fireflies. 
The Wax Insects belong to this family. These creatures are plentiful in China, where 
the waxen secretion is manufactured into many useful articles, and is equal, if not superior, to 
that obtained from the bee. That this creature should produce wax is thought to be very 
marvellous, but there is no reason to consider the fact more wonderful than that the bee should 
secrete a similar substance. There is this difference, that the bee produces the wax from six 
little pockets arranged along the abdomen, whereas the Fulgora pours it from various parts of 
the body, just as the oil is emitted by the meloe-beetle already described. 
