116 IIEMTPTERA. 



sal portion of the prothorax (PI. V., Figs, d-i^, 64, l>') 

 extends backward over the greater part of the meso- 

 thorax and fits it closely, while the sternal portion is 

 firmly soldered to the mesothorax. PL V., Fig. 65 is 

 a side view of the head and thorax. The prothorax 

 (^') has been raised, exposing the forward part of the 

 mesothorax {/>", /-) below. 



The triangular form of the prothorax gives proper 

 support to the narrow head for the work of piercing 

 the tissues of vegetables with the proboscis. Not 

 only is this form of the prothorax in direct correlation 

 with the sucking habits of the insect, but the broad 

 body behind is admirably adapted to the uses of a 

 type that feeds in this way, and walks and runs from 

 preference, not living habitually on the wing. 



The mesothorax (PI. V., Figs. 64, 65, <^") is large, 

 and extends backward in the form of a pointed 

 triangular piece, the scutellum (PI. V., Figs. 6^, 64, 

 65, A"), which nearly conceals the small, dorsal por- 

 tion of the metathorax (Fig. 64, d'"). This scutellum 

 varies greatly in size in different genera, becoming so 

 large in the genus Scutellera (Fig. 74, p. 126) as to 

 cover the abdomen and wings. While the metathorax 

 is ring-like above (PL V., Fig. 64, ^"', p. 115), at 

 the sides it broadens out (PL V., Fig. 65, ^"') and 

 resembles the lateral parts of the mesothorax. The 

 sternum is perforated by two openings of glands which 

 secrete a hquid with a disagreeable odor. According 

 to Professors Verrill and Johnson^ this odor bears the 

 most resemblance to that of the formate of oxide of 



1 Froc. Bost. Soc. Nat. Hist., Vol. XL, p. 160. 



