238 KEPORT OF THE COMMISSIONER OP AGRICULTURE. 



nol uin (PL I, Fig. 3), and the formi&g Cicada begins to issue. Ecdysis 

 is always an interesting phenomenon, and, when closely watched in our 

 Cicada, cannot fail to entertain. 



" The colors ot'.the forming Cicada are a creamy-white, with the excep- 

 tion of tlic reddish eyes, the two strongly contrasting black patches on 

 the prothoras, a black dash on each of the coxai and someUmes on the 

 IVout femora, and an orange tinge at base of wings. 



"There are five marked positions or phases in this act of evolving from 

 the pupa-shell, viz, the straight or extended, the hanging, head dowii- 

 ward ; the c/in(7m^, head upward; the, jlat-icinged, aaiA finally the roo/- 

 winged. In about three minutes after the shell splits, the forming imago 

 extends from the rent almost on the same plane with the pupa, with all 

 its members straightiand still held by their tips within theexnvium (PI. 

 I, Fig. 4). The imago then gradually bends backwards and the members 

 are all loosened and separated. With the tip of the abdomen held within 

 the exuvium, the rest of the body hangs extended at right angles from 

 it, and remains in this position from ten to thirty minutes or more, the 

 wing-pads separating, and the front pair stretching at right angles from 

 the body and obliquely crossing the hind pair (PI. I, Figs. 5, 6) ; they 

 then gradually swell, and during all this time the legs are becoming 

 firmer and assuming the ultimate positions. Suddenly the imago bends 

 upward with a good deal of effort, and clinging with its legs to the first 

 object reached, whether leaf, twig, or its own shell, withdraws entirely 

 from the exuvium and hangs for the first time with its head up (PI. I, 

 Fig. 7). Now the wings perceptibly swell (Fig. 8) and expand until they 

 are fully stretched and hang flatly over the back, perfectly transparent, 

 with beautiful white veining (Fig. 9). As they dry they assume the 

 roofed position (Fig. 10), and during the night the natural colors of the 

 species are gradually assumed (Fig. 11). 



" The time required in the transformation varies, and, though for the 

 splitting of the skin and the full stretching of the wings in the flat posi- 

 tion the time is usually about twenty minutes, it may be, under pre- 

 cisely similar conditions, five or six times as long. But there are few 

 more beautiful sights than to see this fresh-forming Cicada in all the 

 different positions, clinging and clustering in great numbers to the out- 

 side lower leaves and branches of a large tree. In the moonlight such 

 a tree looks for all the world as though it were liill of beautiful white 

 blossoms in various stages of expansion. 



THE CICADA VERSUS CIVILIZATION. 



" That this insect, in its distribution and in its numbers, has been and 

 is being seriously affected by our civilization must be apparent to every 

 observer. The records show that the numbers have decreased in the 

 successive appearances of certain broods, owing largely to the presence 

 t tl' onr domestic animals in the woods. Then, again, the cleariug of laud 

 ::iid the building of towns and cities have all had their effect u].ion tlie 

 increase of this Cicada. There are doubtless many places in Brooklyn, 

 N. Y., where the Insect appeared seventeen years ago in which there, 

 will be none the present year. And similarly I opine that, whereas 

 around every tree that has been planted more than seventeen years or 

 u{)ou land that grew trees seventeen years ago the insect is now abun- 

 dant in Washington, it will scarcely be noticed in any part of the Dis- 

 trict seventeen years hence. I base this opinion upon a new phase in 

 the cicada history, viz, the presence of the English sparrow. It is the 

 first time, perhaps, in the history of the world, that Passer domesticus 



