346 INSECTS INJURIOUS TO VEGETATION. 



and there are also two similar tufts on the middle of the wing. 

 The hind-wings are dusky brown or light brown, with a paler 

 fringe, and are without bands or spots. The wings expand about 

 one inch and a quarter. 



The means for destroying the hop-vine caterpillars are shower- 

 ing or syringing the plants with strong soap-suds, or with a solu- 

 tion of oil-soap in water, in the proportion of two pounds of the 

 soap to fourteen or fifteen gallons of water. 



The foregoing is the only kind of Delta-moth that appears to 

 be particularly injurious to any of our useful or cultivated plants. 



5. Leaf-rollers. [Tortrices.) 



There are many caterpillars that curl up the edges of the 

 leaves of plants into little cylindrical rolls, open at each end, and 

 fastened together with bands or threads of silk. These rolls 

 serve at once for the habitations and the food of the insects ; and 

 to the latter Linnaeus gave the name of Tortrices, derived from 

 a Latin word signifying to curl or twist,. All the caterpillars 

 now put in this tribe are not leaf-rollers. Some of them live in 

 leaf and flower buds, and fasten the leaves together so that the 

 bud cannot open, while they devour the tender substance within. 

 Some live in a kind of tent formed of several leaves, drawn to- 

 gether and secured with silken threads. Others are found in the 

 tender shoots or under the bark of plants. A few bore into 

 young fruits, which they cause to ripen and fall prematurely. A 

 still smaller number of kinds live on the leaves of plants, exposed 

 to view, and without any kind of covering over them.. Most of 

 these insects, when disturbed, let themselves down by threads, 

 like the Geometers. Very iew of them make cocoons ; the 

 greater number transforming within the rolled leaves, or in the 

 other situations wherein they usually dwell. They are furnished 

 with sixteen legs, and their bodies are nearly or quite naked. 

 Many of their chrysalids have two rows of minute prickles across 

 each of the rings of the hind-body, by the help of which they 

 push themselves half way out of their habitations, when the in- 

 cluded moths are about to come forth. 



The moths of this tribe are mostly of small size, very few of 

 them expanding more than one inch. They carry their wings 



