FAMILY riCADID.E. 161 



lull the loiig-HcUloii districts of the State, those which were reclaimed from the forest fifty 

 years ago, will not be so much subject tf) attacks of the kind. Observation at the time of 

 the appearance of these insects will tend to tlirow some light upon the question, whether, 

 fi>r instance, a certain tree was known to have been infested by them. 



The Cicada lays between four and five hundred eggs ; and hence the provision for the 

 continuance of the species, it would seem, is anii>le : in conse<juence, however, of the 

 accidents to which it is subjected in its larva and pupa state, its increase is by no means 

 great, and in tlie older sections of New-York and New-England it certainly doss not hold 

 its own in numbers. 



The larva does not necessarily descend deep into the earth : never beyond the reach of 

 the roots of the trees on which it feeds ; and in some places where 1 have seen it issue 

 from the earth, it could nut have penetrated directly more than six inches, in consequence 

 of the underlying rock. It is hardly necessary to repeat the rdd notion respecting them, 

 that thoy continue to descend lor eight and a half years, and then begin their return to the 

 surface ; yet it is well estal)Iislu(l that they apjiear only at intervals of seventeen years, 

 making some allowance f«>r the Irregular appearance of a few which ma} precede or 

 succeed tlie main brood a year or two earlier or later than the rule allows. For a similnr 

 reason, probably, the cicada does not appear the same year in diflerent parts of the coun- 

 try*. 



Mr. Hahuis has given, in his treatise on insects injurious to vegetation, a long list of the 

 times when and places where the seventcen-ycar locust has made its visits, together with 

 an interesting history of the economy and habits of this singular animal. The insect, ac- 

 conling to the author referred to, does not select an} jiarticiilar si^ecies of tree in preference 

 upon which to deposit its eggs : most, if not all kinds of trees except the pine and fir, 

 have been foimd with their limbs pierced by it. 



The eggs, according to the observations of Miss Mokeis, are hatched in forty-two days : 

 others say in less time ; but however this may be, prior to the time of hatcliing, most of 

 the wounded branches wliich have received eggs are detached, and have fallen to the 

 ground : at least this was the case when they appeared in the vicinity of Tioy about the 

 year 1830. The twigs perish much sooner when wounded by this insect, than if a wound 

 of equal magnitude were inflicted upon them with a knife : indeed, in a xery few hours 

 after receiving a deposit of eggs, the twig is perfectly dead. 



Tlie extent of injury inflicted by the these locusts upon forest and fniit trees does not 

 seem to be very serious : it amounts to only a foreshortening of the limbs ; and if the 

 tree is injured at all, it speedily recovers. The injnry is far less than that which often 

 follows when the wound is made in the axis of growth. No remedy seems to be required, 



• Hauuis : Insccla i«jiiriouM vegetation, ji. 1SX Tho jc/'/fin/f rim njipparcd in Sladison conntv (Kcw-Tork) 

 in 18i>. 



