352 OF INSECTS, &c. 



six species. They take their specific names from 

 the different plants which they frequent ; as the 

 Chermes graminis, or grass bug ; the Chermes 

 ficus, or fig-tree bug, &c. The latter is one of 

 the largest of the genus, and is brown above 

 and greenish beneath. It has four long wings, 

 which are placed in form of an acute roof. The 

 larva, which is of an oblong form, has six feet, 

 and its motion is slow. When it is attempted 

 to catch the Chermes, it makes its escape ra- 

 ther by leaping than flying, by means of its 

 hinder legs, which play like springs. Some of 

 these insects have a manoeuvre worthy of notice. 

 Several species are provided at the extremity of 

 their body with a small sharp -pointed imple- 

 ment, but which lies concealed 5 and this they 

 draw out in order to deposit their eggs, by 

 making a puncture in the plant that suits them. 

 By this method, the fir-tree Chermes produces 

 that enormous scaly protuberance which is to be 

 found at the summit of the branches of that 

 tree, and which is formed by the extravasation 

 of the juices occasioned by the punctures. The 

 young larvse shelter themselves in cells contained 

 in the tumour. The directions for destroying 

 the Coccus are applicable to this insect. 



The Thrips. 



The Thrips, of which there are eleven species, 

 also belongs to the order Hemiptera. This insect 



