HEMIPTERA. 181 



Sandwich, and Falmouth, in the year 1804; but, if the exact 

 period of seventeen years had been observed, they shoukl have 

 returned in 1803. Circumstances may occasionally retard or 

 accelerate their progress to maturity, but the usual interval is 

 certainly seventeen years, according to the observations and 

 testimony of many persons of undoubted veracity. Their 

 occurrence in large swarms at long intervals, like that of the 

 migratory locusts of the east, probably suggested the name of 

 locusts, which has commonly been applied to them in this 

 country. The following extract from a letter* from the late 

 Rev. Ezra Shaw Goodwin, of Sandwich, contains some in- 

 teresting particulars which this gentleman had the kindness to 

 communicate to me. 



" I have not been unmindful of what you said to me respect- 

 ing the locust insects, nor of the promise I made you with 

 respect to them. They appeared in this town in the year 

 1821, in the middle of June. Their last previous appearance 

 was in 1804, and their last, previous to that, was in 1787. I 

 ascertained these periods from the statements of individuals, 

 who remembered that it was locust-year, when this or that 

 event occurred ; as, when this one was married, or that one's 

 eldest son was born ; events, the date of which the husband 

 or the parent would not be very likely to forget. The remem- 

 brance of all, though fixed by different events, concurred in 

 establishing the same years for the appearance of the locusts. 



"I first took notice of them in 1821, on the 17th of June, 

 from their noise. They appeared chiefly in the forests, or in 

 thickets of forest-trees, principally oak. Their nearest distance 

 from my dweUing cannot be far from a mile; yet, at a still 

 hour, their music was distinctly heard there. On going to visit 

 them, I found the oak-trees and bushes swarming with them 

 in a winged state. They came up out of the ground a creep- 

 ing insect. Very soon, after they had arrived on the surface 

 of the earth, the skin, or rather the shell of the insect, burst 

 upon the back, and the winged insect came forth, leaving the 

 skin or shell upon the earth, in a perfect form, and uninjured, 

 saving at the rupture on the back; showing an entire with- 



• Dated Oct. 19, 1832. 



