428 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, anil 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 speries that it can lie 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 

 lie 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 

 Cicada? 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 Fulgoridse, 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. 



