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whitish or gray, shaded darker towards the edges. When the motli is at rest, 

 with closed wings, upon the bark of trees or on fence-rails, it is difficult of dis- 

 covery, its color so closely resembling that of the objects on which it rests ; 

 but as they are attracted by light, numbers of them may be caught in summer 

 evenings flying around the candle or lamp. 



In small gardens cut-worms may easily be destroyed by digging them from 

 their holes near the plants injured, and crushing them ; but as this would be 

 impracticable on large plantations, we should encourage the birds, who are the 

 true agents appointed by Nature to keep in check the insects injurious to our 

 crops. Young pigs also eat the chrysalides, and as the moths are attracted by 

 light, burning brush, during the season the females are depositing their eggs, 

 might diminish their numbers. 



After the cut-worm, the next insect at- 

 tacking the cotton plant is the louse, 

 (aphis,) which injures it at all stages of 

 its growth, by puncturing the terminal 

 shoots and young leaves with its })iercer 

 and extracting the sap. This constant 

 drainage of saj) enfeebles the plant, causes 

 the leaves to curl, become distorted, turn 

 yellow, and finally fall, eventually killing 

 the plant, if their ravages are not checked. 



The most familiar type of this insect is the small, green louse, so common on 

 rose-bushes and grape-vines. The natural history of the cotton louse is as fol- 

 lows : The female in late autumn deposits eggs which retain their vitality 

 through the winter, and in the spring produce young lice, which at once attack 

 the tender plant. During summer, however, the young produced are mostly 

 females, and wingless, and are vivipai'ous, bringing forth their progeny alive, 

 and not by eggs as in the fall These young, without connexion with males, 

 also bring forth living young for several generations. This fact accounts for 

 their excessive multiplication. In the fall winged males become more numer- 

 ous, and, after pairing, the females deposit their eggs for the spring generations. 



The honey-dew, found on leaves under places frequented by these lice, is a 

 sweet, excrementitious matter ejected by them, and is greedily sought for by 

 myriads of ants, which may be seen on the plants infested by lice, often 

 gently tapping them with their autenuiE to induce fhem to emit the substance. 

 Some authors are of the opinion that this honey-dew is discharged from two 

 horns or tubercles on the upper side of the hind part of the abdomen, but De 

 Geer and others state that it is discharged from the end of the abdomen, and 

 that the tubes are probably breathing organs filled Avith air cells, and that the 

 sap sucked from the plant is sooner changed into nourishment by coming in 

 contact with these tubes. 



These plant lice are about one-tenth of an inch in length, and generally of a 

 greenish tint, but vary very much in color, many being almost black ; indeed, 

 they may be seen of all shades, from light-green to black, feeding together on 

 the same stalk. It is probable, therefore, that the color is not owing to the 

 plant upon which it feeds, but from some peculiar condition of the insect itself. 



When old cotton plants are suffering from the attacks of the louse, many 

 planters have the tops cut off and burned, thus destroying many. The com- 

 mon methods of fumigation — whale-oil soap, snuff, &c. — as used in greenhouses 

 and small gardens, would be of no avail on an extensive cotton plantation ; and 

 until some more practicable means are devised the planter will have to rely 

 principally upon other insects which feed upon the aphis and check their in- 

 crease. 



The principal insect enemy of the plant lice is the lady bug, (coccinella,) 

 which, iu both larva and perfect state, is incessantly waging war upon them, 



