130 



Ereatfurp of Natural ^f 



divisions of the abdomen marked by nu- 

 merous scarlet rings or bands ; and the 

 Cicada viridis, a large species, native of New 

 Holland, of a beautiful green colour, with 

 the transparent wings ornamented by green 

 veins. 



Cicada scptendecim, or Seventeen-year 

 Cicada. It is well remarked by Dr. Thad- 

 deus Harris, that " the duration of life in 

 winged insects is comparatively very short, 

 j seldom exceeding two or three weeks in ex- 

 tent, and in many is limited to the same 

 number of days or hours. To increase and 

 multiply is their principal business in this 

 period of tlieir existence, if not the only one, 

 and the natural term of their life ends when 

 this is accomplished. In their previous 

 states, however, they often pass a much 

 longer time, the length of which depends, in 

 great measure, upon the nature and abun- 

 dance of their food." The harvest-flies con- 

 tinue only a few weeks after their final 

 transformation, and their only nourishment 

 consists of vegetable juices, which they ob- 

 tain by piercing the bark and leaves of 

 plants with their beaks ; and during this 

 period they lay their eggs and then perish. 

 They are, however, amply compensated for 

 the shortness of their life in the winged state 

 by the length of their previous existence, 

 during which they are wingless and grub- 

 like in form, and live under ground, where 

 they obtain thtir food only by much labour 

 in perforating the soil among the roots of 

 plants, the juices of which they imbibe by 

 suction. To meet the difficulties of their 

 situation and the precarious supply of their 

 food, a remarkable longevity is assigned to 

 them ; and one species has obtained the 

 name of Cicada septendecim, on account of 

 its life being protracted to the period of 

 seventeen years. This insect, in the perfect 

 state, is of a black colour, with transparent 

 wings and wing-covers, the thick anterior 

 edge and larger veins of which are orange- 

 red, and near the tips of the latter there is a 

 dusky zigzag line in the form of the letter 

 W ; the eyes when living are also red ; the 

 rings of the body are edged with dull orange; 

 and the legs are of the same colour. The 

 wings expand from two inches and a half to 

 three inches and a quarter. 



In those parts of the United States, as we 

 are informed, which are subject to the visi- 

 tation of this Cicada, it may be seen in fo- 

 rests of oak about the middle of June. Here 

 such immense numbers are sometimes con- 

 gregated, as to bend and even break down the 

 limbs of the trees by their weight, and the 

 woods resound with the din of their discord- 

 ant drums from morn to eve. After pairing, 

 the females proceed to prepare a nest for the 

 reception of their eggs. They select, for this 

 purpose, branches of a moderate size, which 

 they clasp on both sides with their legs, and 

 then bending down the piercer at an angle of 

 about forty-five degrees, they repeatedly 

 thrust it obliquely into the bark and wood 

 in the direction of the fibres, at the same 

 time putting in motion the lateral saws, and 

 in this way detach little splinters of the wood 

 at one end, so as to form a kind of fibrous 

 lid or cover to the perforation. The hole is 



, 



pting to fly, and soon dies. 

 hough the Cicadas abound most upon 



bored obliquely to the pith, and is gradually 

 enlarged by a repetition of the same opera- 

 tion, till a longitudinal fissure is formed of 

 sufficient extent to receive from ten to twenty 

 eggs. The side pieces of the piercer serve as 

 a groove to convey the eggs into the nest, 

 where they are deposited in pairs, side by 

 side, but separated from each other by a 

 portion of woody fibre, and they are im- 

 planted into the limb somewhat obliquely, 

 so that one end points upwards. When two 

 eggs have been thus placed, the insect with- 

 draws the piercer for a moment, and then 

 inserts it again and drops two more eggs in 

 a line with the first, and repeats the opera- 

 tion till she has filled the fissure from one 

 end to the other, upon which she removes to 

 a little distance, and begins to make another 

 nest to contain two more rows of eggs. She 

 is about fifteen minutes in preparing a single 

 nest and filling it with eggs ; but it is not 

 unusual for her to make fifteen or twenty 

 fissures in the same limb ; and one observer 

 counted fifty nests extending along in a line, 

 each containing fifteen or twenty eggs in 

 two rows, and all of them apparently the 

 work of one insect. After one limb is thus 

 sufficiently stocked, the Cicada goes to an- 

 other, and passes from limb to limb and 

 from tree to tree, till her store, which con- 

 sists of four or five hundred eggs, is ex- 

 hausted. At length she becomes so weak by 

 her incessant labours to provide for a suc- 

 cession of her kind, as to falter and fall in 

 attem 

 Alt 



the oak, they resort occasionally to other 

 forest-trees, and even to shrubs, when im - 

 pelled by the necessity for depositing their 

 eggs, and not unfrequently commit them to 

 fruit-trees, when the latter are in their vici- 

 nity. Indeed there seem to be no trees or 

 shrubs tbat are exempted from their attacks, 

 except those of the pine and fir tribes, and of 

 these even the white cedar is sometimes in- 

 vaded by them. The punctured limbs lan- 

 guish and die soon after the eggs which were 

 placed in them are hatched ; they are broken 

 by the winds or by their own weight, and 

 either remain hanging by the bark alone, or 

 fall with their withered foliage to the ground. 

 In this way orchards have suffered severely 

 in consequence of the injurious punctures 

 of these insects. The eggs are one twelfth 

 of an inch long, and one sixteenth of an 

 inch through the middle, but taper at each 

 end to an obtuse point, and are of a pearl- 

 white colour. The shell is so thin and deli- 

 cate that the form of the included insect can 

 be seen before the egg is hatched. 



The young insect when it bursts the shell 

 s one sixteenth of an inch long, and is of a 

 yellowish white colour, except the eyes and 

 the claws of the fore-legs, which are reddish; 

 and it is covered with little hairs. In form 

 t is somewhat grub-like, being longer in 

 proportion than the parent insect, and is 

 furnished with six legs, the first pair of 

 which are very large, shaped almost like 

 lobster-claws, and armed with strong spines 

 beneath. On the shoulders are little pro- 

 minences in the place of wings ; and under 

 the breast is a long beak for suction. These 



