TENTH EEPORT OF THE STATE ENTOMOLOGIST 421 



ties, and was also, by request, copied in many of the local papers of 

 the several counties : 



IjNrvaHSITY OF THE S FATE OF NeW YoRK, ) 



Office of thb State Estomologist. ' 

 The Periodical Cicada, or the " Sevsnteen-Year Locust," 



Perhaps no known insect has more interest connected with it than 

 the one above named. The life-period of none other approaches it in 

 length. Although its remarkably long life is doubted by many, yet no 

 scientific fact has been better established than that from the time its 

 Ggg^ are deposited in the slits made in the twigs of trees, to that in 

 which the perfect insect is developed from the eggs and appears 

 abroad, soon to dejDOsit its eggs, seventeen years (less about one month) 

 will have intervened. 



In some localities in the United States the periodical Cicada (usually 

 but improperly known as the seventeen-year locust) appears at shorter 

 intervals than this — in four or six or other number of years; but these 

 are of other broods which extend over certain localities of greater or 

 less extent, but each one always true to its appointed time of seventeen 

 3'ears. The only exception to this is, that in some of the Southern 

 States, a race occurs, indistinguishable ia appearance from the others, 

 but the several broods of which appear every thirteen years. 



In the State of New York, six distinct broods of the seventeen- year 

 cicada are known. The one that is with us at the present time, and of 

 which the first insects made their appearance about the 25th of May, has 

 been designated as the Hudson river valley brood. Dr. Fitch, who 

 was the first to indicate its boundary, states, in his I^irst Report on the 

 Insects of Neio York: "Its northern limit is in the vicinity of Schuy- 

 lerville and Fort Miller [Saratoga and Washington counties], and thence 

 reaches south along both sides of the Hudson to its mouth, where it 

 extends east at least to New Haven in Connecticut, and west across 

 the north part of New Jersey and into Pennsylvania." 



How far inward in each direction from the river this brood extends 

 is not known, nor whether ia any instance it reaches the outer limits of 

 any of the twelve eastern riv'er counties. Definite knowledge of its 

 range would be of interest and of use, and would aid in mapping the 

 infested region. Such a map, made from sufficient data, would serve 

 to show in subsequent returns, whether the successive broods are 

 lessening, both in the number of insects and in the territory occupied 

 by them, as is generally believed. 



Most persons who can recall a " locust year," are familiar with the 

 appearance of the insect in its pupal and winged stages; but as aid to 



