169 ORDER HOMOPTERA. 



In the eighth volume of the Encyclopsedia Americana, Dr. Harris has described the 

 leafhopper, Tettigonia vitis. It is about the tenth of an inch long, and arrives at maturity 

 in the month of August : it is of a pale straw-color, and inhabits both the native and 

 foreign grape vines, and, in some seasons, is so numerous as to affect seriously the vines 

 and fruit. They adhere to the underside of the leaves, and hence the remedy proposed, 

 which consists in fumigation with tobacco, will be more effectual than il" they inhabited 

 the upper side. For the purpose of fumigation, the vine or its trellis should be covered 

 with a tent, and the process may be persisted in until the insect is thoroughly routed or 

 destroyed. 



Rosebushes sometimes become infested with a kind of leafhopper, the Tettigonia rosa^ 

 which may be treated in the same way. 



As the insects of this family hop briskly, they cannot be dislodged from the vines by 

 shaking, nor is it practicable to catch them : it hence becomes necessary to destroy them 

 by fumigation, or by the application to the leaves and vines of some substance destructive 

 to the insects, but which will not injure the plant. Whale-oil soap in solution is another 

 remedy whose application has been followed with success. 



As these insects take refuge among the fallen leaves and underlying grass, where they 

 survive the winter, the leaves and grass should be carefully removed and burned, either 

 after the weather has become cold in the autumn, or in the spring before vegetation has 

 put forth. All these methods should be resorted to, where vines suffer from too great an 

 abundance of these insects. 



ApMdiclae. 



The aphidians ( plant-lice) are a group of insects with soft bodies of an oval form, and 

 furnished posteriorly with two tufts or pores. The females are generally wingless, though 

 not always. The upper pair, answering to the wing-covers in the Hemiptera proper, are 

 larger, and are used for the pui-pose of flight, or to assist in leaping. 



The leaping plant-lice belong to the Genus Psylla : the young are covered with a 

 cottony substance, and are found upon the alder and some other plants in the spring. 



The genus to which the name Aphis has been given, from which the name of the family 

 is derived, and which signifies to exhaust, is one of the most remarkable in the class of 

 insects : feeble and entirely unprotected, the insect is crushed by a touch, or swept away 

 by a breath. It is, however, provided with the means of increase to an immense extent ; 

 and, hence. In consequence of this extraordinary power, in virtue of its numbers alone it 

 is competent to inflict the most serious injury upon the plants it inhabits. Most plants are 

 infested with them ; and each particular kind of plant, shrub and tree, supports its own 

 peculiar species, though it does not seem to be proved that the juices of many plants may 



