HEMIPTEEA. 119 



Geoffrey calls this insect " le Petit Diable." " Le Petit Diable," 

 says he, "is of a dark blackish-brown. Its head is flat, projecting 

 but slightly, and, as it were, bent downwards. Its thorax, which is 

 rather broad, has two sharp horns, which terminate in pretty long 

 points on the sides. In the middle of the thorax is a crest or 

 comb, which, prolonged into a sort of sinuous and crooked horn, 

 terminates in a very sharp point, reaching to within one quarter 

 of the extremity of the wing-cases. These viz., the wing cases 

 are dark, with brown veins, and the wings, shorter than their 

 cases, are rather transparent. It jumps very well, and it is not 

 easy to catch it." * 



The Petit Diable of Geoffroy is the Centrotus cornutus of modern 

 naturalists. This curious little insect belongs to a strange and 

 remarkable group, whose thorax takes the most extraordinary and 

 most varied forms, as may be seen in Fig. 86, which represents, 

 somewhat magnified, many of these insects. Nearly all inhabit 

 Guyana, the Brazils, and the islands of Florida. 



We will now examine one of the most interesting groups to 

 study from different points of view that of the Plant-lice. 

 These insects have for a long time attracted the attention of 

 observers. They are so abundant that all our readers have seen 

 them, and there are few plants in our fields or gardens which do 

 not nourish some species. How often does one hesitate in gather- 

 ing a rose or a bit of honeysuckle, for fear of touching the unat- 

 tractive guest of those charming flowers ! 



During the whole of the summer, one sees on the branches, on 

 the leaves, but principally on the young shoots of the rose-tree, 



Figs. 87, 88. -Winged Aphides, or Plant-lice (magnified). 



large companies of green plant-lice, which subsist on the sap of 

 the tree. Some are provided with wings (Figs. 87, 88), others are 



* " Histoire abregea des Insectes, dans laquelle ces animaux sont ranges dans un 

 ordre methodique." In 4to, an VII. de la Republique, tome i. p. 423. 



