26 REPORT OF THE COMMISSIONER OF AGRICULTURE. 



and penetrating to the pith in the terminal shoots and small branches 

 of oak, apple, and other deciduous trees. These slits arc made by the 

 ovipositor ot the female. The young larA'a3 hatch out in about six 

 weeks, i'all to the ground, and immediately bury themselves under the 

 earth, where they are said to remain nearly seventeen years in thelarvoe 

 state, feeding on succulent roots of trees and shrubs. When about to 

 change into puptc, the larva) work their way to the surface of the 

 groujid, shed their outer skins, and assume the pupa state, somewhat 

 resembling the perfect insect, but having thick and strong fossorial or 

 digging fore legs, with only wing-cases, and utterly incapable of flight. 

 This pupa state is said to last only a few days, during which the pupa 

 remains near the orifice of its subterranean tunnel. Mr. Rathvon, how- 

 ever, states that in localities which are low and flat, and the drainage is 

 imperfect, they construct galleries of earth, 4 to G inches above ground, 

 leaving an orifice for egress even vvith the surface, in the upper end of 

 which the pupa would be found waiting their appointed time of change. 

 They would then back down below the level of the earth and under- 

 go their transformations in the usual manner. But in all the cases 

 observed when these locusts or liarvest-flies abounded near the agri- 

 cultural college in Maryhind, the pupai were found in somewhat cyl- 

 indrical holes or burrows, some of them having even burrowed up- 

 ward through hard gravel roads, as before stated. When ready to 

 change into perfect insects, they crawled out of these holes, made their 

 way as best they could up the neighboring trees, stone fences, and rails, 

 and attached themselves by the strong claws of their feet to some 

 solid rough substance ; the skins of the pupa), hardened, split open 

 down the back and thorax, and the perfect harvest-fly emerged into the 

 open air from the dry old skin, after waiting some time to dry its yet 

 damp wings, it eventually flew away to join its noisy companions on 

 the neighboring trees. In these cases, however, no gallery whatever 

 was made by any of the larvae observed, but the insects emerged from 

 simple holes in the ground. The situation was high, the soil gravelly, 

 with no swamps in the immediate vicinity. For weeks afterward the 

 trees and fences were literally covered with the dried-up and split skins 

 of the pupcB still clinging to them by means of their strongly-hooked 

 claws, appearing to the casual observer as if they were still alive and in 

 the act of ascending the trees. At the end of the season many of these 

 insects were observed flying about the Maryland woods with only about 

 two-thirds of the abdomen remaining, and that portion perfectly dry and 

 hollow, as if the end had been bitten off by domestic fowls or other birds 

 or broken off by accident ; sometimes, however, the hollow portion was 

 partially filled with a brownish powder. On this subject Dr. Leidy,in the 

 Proceedings of the Academy of Natural Sciences in Philadelphia, states 

 that the cicada is liable to bo attacked by a peculiar fungus, the poste- 

 rior portion of the abdomen of the male insects being filled with a green 

 fungus. The abdomen of the infected males was usually inflated, brit- 

 tle, and totally dead while the insect was yet flying about 5 when, upon 

 breaking off the hind part of the abdomen, the dust-like spores would 

 fly as if from a small puft'-ball. ]\Ir. Ti. W. Ward, of Ohio, in the Amer- 

 ican Entomologist, (vol. 1, p. 117,) states that this mold or fungus seems 

 to be a drying up of the membranes of the abdomen, and it is generally 

 of a brown color, dry and brittle. lie thinks, likewise, that these males 

 in copulation break off one or more of t\m posterior joints of the ab- 

 domen, and that this " dry-rot " may be the result of the broken mem- 

 branes. He adds, also, that he never found a perfect male thus 

 affected in the early part of the season. Some naturalists assert that 

 there are two, if not more, varieties of this insect: one ai^pearing 



