Page:The American Cyclopædia (1879) Volume VIII.djvu/515

 HARVEST FLY 501 number of students from 413 to 706, the libra- ry from 110,000 to 136,000 volumes, and the number of scholarships from 41 to 92. Ac- cording to the triennial catalogue of 1872, the university had conferred 12,175 degrees, in- cluding 596 honorary. The number of gradu- ates from the college was 8,330, of whom 3,088 rere living; 2,036 students had graduated )m the medical, 1,720 from the law, 428 the theological, 183 from the scientific, J9 from the dental, and 4 from the mining "lool. See " A History of Harvard Universi- r," from 1636 to 1776, by Benjamin Peirce L833) ; " The History of Harvard University," Josiah Quincy (1840); " A Sketch of the fistory of Harvard College," by Samuel At- is Eliot (1848) ; and " Biographical Sketches Graduates of Harvard University" (1642- 3), by John Langdon Sibley (vol. i., 1873). HARVEST FLY, a hemipterous insect, of the li vision homoptera (from having the wing cov- of the same texture throughout), of the lily cicadadm, and chiefly of the genus cicada (Oliv.), improperly called locusts in America, [t has been known from remote antiquity, and i the TTTI% of the Greeks, cicada of the Latins, lie of the French, and cicala of the Italians, le harvest flies or cicadians have short anten- j, conical, six-jointed, and tipped with a little Bristle ; wings and wing covers in both sexes, iclined at the sides of the body ; three joints the tarsi ; a hard skin ; and in the female a iercer lodged in a groove under the end of body. Those of the genus cicada, which las been improperly translated grasshopper, easily known by their broad heads ; their convex, and brilliant eye on each side, and iree simple eyes on the crown ; their wings id the covers veined and transparent ; and an levation on the back part of the thorax in the >rm of an X. The males make a loud rattling und by means of a kind of kettle-drum appa- Jus on each side of the base of the abdomen ; lis is covered by two large oval plates, and -insists of a cavity containing plated folds of parchment-like membrane, transparent as lass ; these are moved by muscular cords, 'hose alternate and very rapid contractions relaxations produce a corresponding ten- ion and looseness of the membranes and a msequent harsh rattling noise, heard to a msiderable distance; the action is assisted the rapid movements of the wings, and the >und is rendered more intense by the reso- ance of cavities within the body protected )y valves. The piercer has two lateral plates rthed like a saw in the lower portion, and tween them a spear-pointed borer. They lave not the power of leaping like locusts and ior thighs are armed with two stout spines, i the perfect state they live only a few weeks, 3rforming the work of reproduction and then lying; in the larva state they are wingless "id subterranean, living on the juices of roots, id passing a series of years in the ground. The C. septendecim (Linn.) is called the 17 years locust from the prevalent belief that its life is prolonged to that extent in the imperfect state ; undoubted testimony, both from popular and scientific sources, proves that these insects usu- ally appear at intervals of 17 years, but acci- Seventeen Years Locust (Cicada septendecim). dental circumstances may accelerate or retard their progress to maturity ; though they ap- pear in some parts of the country probably every year, and indeed in all districts except northern New England and to the north of that, the lineal descendants of each swarm ap- pear only every 17 years; the popular name of locust was doubtless derived from this fact of their appearance in large swarms after long in- tervals of time, like the locusts of the East. In the perfect state this harvest fly is of a black color, the anterior edge and principal veins of its transparent wings and covers being orange red ; near the tips of the covers there is a dusky zigzag line in the form of the letter W, which by the superstitious is supposed to indicate ap- proaching war ; as the mark on the other wing would be inverted like the letter M, the two were supposed to announce a war with Mexico during their appearance in Louisiana in 1835, which however did not arise until some years after; the eyes are red, with metallic reflec- tions; the rings of the body are edged with dull orange, and the legs are of the same color ; the expanse of wings is from 2| to 3J in. Though found upon almost all kinds of trees, except most evergreens, they prefer forests of oaks. The perfect insects "emerge from the ground from February to the middle of June, according to latitude and the warmth of the season ; their numbers are often so great that the limbs are bent and broken by their weight, from six to eight being sometimes seen on every leaf; the drumming sound is heard from morn- ing to night, but most loudly between the hours of 12 and 2. They are not found in low alluvial lands, and a dry air is necessary for the perfection of the drumming. The males perform the act of reproduction and soon die ; they present scarcely a trace of digestive ap- paratus, and probably take no nourishment; the sexual system is fully developed on emer- gence from the ground, each of their 500 sperm cells containing about 1,000 spermatozoa. The females have each about 500 eggs, of about 1 U of an inch in diameter, which when de- posited are twice that size ; their digestive sys-
 * rasshoppers ; the legs are short, and the ante-