ENTOMOLOGIST AND BOTANIST. 



265 



plentiful in Virginia as to strip the Oak-trees 

 bare." The destruction it caused in some of the 

 Eastern States in 3806 and 1807 is sufficient to 

 decide this question; but there is every reason 

 to believe that in the South and West its injuries 

 are of still vaster extent. "We published last 

 month (p. 245) an account of its injuries at Dcs 

 Arc, Arkansas, and for the past two years it has 

 been quite destructive both to forest and orchard 

 trees, in many parts of Missouri. In fho 0;ik 

 timber these worms prefer trees of the Black Oiik 

 group, and will seldom touch the AVhite Oak in 

 bodies, though when scattered among the other 

 kinds, they attack it also. 



AUTIFICIAI, KEMKDIKS. 



From the time they are born till after the third 

 moult these worms will drop and suspend tliem- 

 selves mid-air, if tlie liranch upon wliii'h they 

 are feeding be suddenly jarred. Therefore when 

 they have been allowed to nudtiply in an orchard 

 this habit will suggest various modes of destroy- 

 ing them. Again, as already stated, they can often 

 be slauglitered en masse when collected on the 

 trunks during the last moulting pei'iod. They 

 will more generally be loniid on the leeward 

 side of the tree if the wind lius been blowing in 

 the same direction for a few days. The cocoons 

 may also be searched for, and many of the moths 

 (■aught by attracting them towards the light. 

 But preeminently the most etfective artificial 

 mode of preventing this insect's injuries is to 

 search for and destroy tlie egg-masses in the 

 winter time when the trees are leafless. Not 

 oidy is (his course the more etHcient because it 

 in more easily pursued, and nips the evil in 

 the bud, but for the leason that, in destroying 

 the eggs only, we in a great measure evade 

 killing, and consequeidly cooperate with, the 

 natural parasites presently to be mentioned, 

 which infest the worms themselves. A pair of 

 pruning shears attached to the end of a pole, 

 and operated by a coid, will be found very 

 useful in clipping off the eggs; or, as recom- 

 mended by Mr. Ferris, a more simple instru- 

 ment may be made by fastening a piece of an 

 old scythe to a pole. If the scythe is kept sharp, 

 the twigs may vei-y handily be clipped with this 

 instrument. Tarred bandages, or any of the 

 many I'cmedies used to prevent the female Can- 

 ker-worm from ascending trees, can only be 

 useful with the Forest Tent-caterpillar when it 

 is intended to temporarily protect an uninfested 

 tree from the straggling woims which may travel 

 from surrounding trees. 



NATUlt.VI. KEMEDIKS. 



It is always wise to cooperate, whenever we 

 can, with our little friends among the Bugs, and 



it is consequently very necessary to be aci|uaint- 

 ed with them. It happens, fortunately, that 

 we have several which aid us in keeping the 

 Tent-caterpillar of the Forest in check, and in 

 the natural forest we must trust entirely to 

 these auxiliaries, as the mechanical means that 

 can profitably be employed in a moderate sized 

 orchard are impi'acticablc in broad extents of 

 timber. Indeed, these cannibals and parasites 

 do their work so effectually that this caterpillar 

 is seldom exceedingly numerous for more than 

 two successive years in one locality. It pre- 

 vails suddenly in great numbers, and again is 

 scarcely noticed for years, very much as is the 

 case with the true Army-worm. Thus, after 

 attracting such general attention in ]8<i7 in 

 many parts of the East, it has scarcely been 

 noticed since. This is its history everywhere, 

 and we may reasonably liope that in those parts 

 of the West where it has been cutting such a 

 figure the present summer, it will suddenly be 

 so subdued as not to be noticed for some years 

 to come. Its undue increase but combines the 

 assaults of its enemies, until they multiply so 

 as to gain the ascendency. Then, from insufll- 

 ciency of food these enrniies suddenly decrease 

 in numbers, and their natural prey has a chance 

 to increase again. And so it goes on in the 

 "Struggle for Life,"' and in the great compli- 

 cated net-work in which every animal oi'ganism 

 is involved: a check here and a check there, 

 and no one of all the myriad forms allowed to 

 keep the ascendency beyond a limited time. 

 The most efficient cannibal insects in checking 

 the increase of this Forest Caterpillar, are the 

 larger Ground-beetles belonging to the genus 

 fl-'i^'. HIS ] 



Ciilois— Mftiillir giTi'ii, iiuriilf ami copper. 



Colosoma. These beetles will pounce upon the 

 worms with astonishing greed, and are especially 

 prone to attack them when helplessly collected 

 together during the moulting periods. The 

 llummaging (Jround Beetle {Colosoma scruta- 

 tor, Fabr.), which every one will recognize from 



