502 HARVEST FLY tern is complete, and the demand for food to develop the eggs must be satisfied during their longer life ; the females are one third smaller than the males. In order to deposit her eggs, the female clasps the smallest twig of a tree with her legs, and introduces the piercer to the pith obliquely and in the direction of the fibres, detaching little splinters by the lateral saws at one end to serve as a cover to the per- foration ; after boring a hole long enough for about 16 eggs, she introduces them in pairs side by side, but separated slightly by woody fibre, and standing obliquely upward; after making a nest and filling it in a space of 15 minutes, she makes others on suitable twigs until her stock is deposited ; by this time in- cessant labor has so weakened her that she drops exhausted from the tree, and soon dies. The eggs are pearl white, very delicate, and are hatched in from three to six weeks, ac- cording to favoring circumstances. The twigs pierced by the insect wither and fall to the ground, either on account of the wound or be- cause such are selected as would soon fall from natural causes ; in this way many of the larvae reach the earth, but most are developed on the trees ; the emerging larva is about y 1 ^ of an inch long, hairy and grub-like, of a yellow- ish white color, with six legs, the first of which are strong like lobster claws, and spiny beneath ; there are rudiments of wings, or little prominences, on the shoulders, and under the breast is a long sucking ciliated tube with a cen- tral tongue. Active on leaving the egg, they in a few moments drop to the ground, and at once bury themselves beneath the surface by means of their fore feet; they follow the roots of plants, perforating them with their beaks and sucking their juices ; they do not descend very deeply into the soil, and change but little during their long subterranean abode except in size and in development of the rudimen- tary wings. As the time of transformation approaches, they gradually advance toward the surface in cylindrical and circuitous passages, about half an inch in diameter and from a depth of one or two feet ; now become pupse, they gradually acquire strength for their final change ; they leave the earth in a warm night and as- cend trees, on which in a short time the pupa skin bursts on the back, and the perfect cicada comes forth. The ground is sometimes riddled like a honeycomb by their numbers, which in about six weeks are all dead. Did these in- sects appear every year or two in the same locality, fruit and forest trees would suffer much from their attacks, even though they only rob roots of juices ; but fortunately they appear only at long intervals, and their eggs are eaten from the beginning by ants and other insects ; the larvae are also devoured by the same in- sects, by birds (especially woodpeckers), by toads and frogs, and other reptiles ; when turn- ed up by the plough, blackbirds and hogs eat great numbers of them ; many perish in their wooden prison, and others are killed by the fall from the trees; as they generally occur in swarms containing about the same number at each period, of course only a small propor- tion of the eggs laid can ever produce the per- fect insect, probably not more than two of the deposit of each female arriving at matu- rity. Another American species is the dog- day cicada (G. canicularis, Harris), so called from the time of its first appearance on July 25 ; it is about If in. long, with a spread of 3 in. ; it is black above, with a powdery white substance on the under parts, and with green markings on the head, thorax, wing covers, and legs. These and several other species have the drumming apparatus, which is always in- tegumental, having no relation to the respira- tory system ; the sound in some of the large southern individuals continues for nearly a minute. Other harvest flies of the same fam- ily, but principally of the genus membracis (Fabr.), have only two eyelets ; they are not furnished with a musical apparatus, but have the faculty of leaping a distance of 5 or 6 ft. ; European Harvest Flies. 1. Cicada plebeia. 2. Cicada oral. they are more properly called tree-hoppers. For full details and references in regard to the American cicadada, the reader may con- sult Dr. Harris's work on " Insects Injurious to Vegetation." The European species do not pass more than a year in their subterranean abode. The C. plebeia (Linn.) is the largest, and is probably the one sung by poets of anti- quity, especially by Anacreon and Virgil. These insects were so highly esteemed by the Athe- nians that they wore golden images of them in their hair; they, however, were also es- teemed as food, just before the conclusion of the nymph state ; they are said to be sold in South American markets, and, freed from the head, wings, and legs, to be roasted and ground into flour. More than 60 species have been de- scribed, spread over almost all the warm regions of the earth. The C. plebeia is black, with reddish spots on the thorax and wing covers. The C. orni, common in central and southern Europe, is about an inch long, yellowish mixed with black ; by their wounding certain species
