€mx^ii Stjfitcntbccim. 



I!v a. 0. OIini^PTTHS. 



(Ucnd, March 'Mh, 1880, Iff ore ilia lilntnmolo(]ir,nl Bcclion.) 



THFi Rovontoon-yoars' oioadn,, or us it is of ton callod in 

 tho Unitod States, with charantoristic Arnorioan disre- 

 gard of ontomologioal exactness, the soventeen-years' looust, 

 made its first rocordod appearance in Plymontli, Mixss., in 

 tho year 1633. " At that time," says Governor Morton, 

 " there was a numerous company of flics, which were like 

 for bigness unto wasps or humhloboos. They came oul- of 

 little holes in the gr'ound, and did oat np the green things, 

 and made such a constant yelling noise as made tho woods 

 ring of them, and ready to deafen the hearers." Judge 

 Davis, in tho Appendix to his odiiiion of Seorotaiy Horizon's 

 " Memorial," says that those insects appeared in PlyniouIJi, 

 Sandwich, and Falmouth, Mass., in 1804 ; hut it the regular 

 snvontoen-year interval had boon exactly obsorvod, this last- 

 mentioned visitation should liavo oooui'red in 1803. No 

 doubt seasonal irrogidarities nuiy at times quicken or re- 

 tard their appearance, but in nearly every case tho interval 

 appears to bo exactly sovonteen .years. A I I'liiladolphia their 

 first recorded occurrence took place in 1715, which will not 

 agree with tho dates of tho Plymouth visitations; tho times 

 liowover, appear to va,ry in (lilIcr(>Tit locaiitiiis, tliough prc- 



84 



