410 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.54. 



Dacyrtocara oncometopiae (Halictophagiclae) has the same type 

 of prosterniim but lacks the tiny poststernenum. The pronotum is 

 pushed far forward in the head, and the pleurites are narrow strips 

 almost invisible from above, being inclosed in the head (pi. 74, fig. 2). 



Xenos hubhardi (Xenidae) has the pronotum simple, but the ster- 

 num is transversely divided into a narrow eusternum and a slightly 

 Ijroader band, which is longitudinally divided and has a posterior 

 projection about the middle of each piece to which the coxa is at- 

 tached. This piece is therefore the sternellum+precoxale+tro- 

 chantin+episternum+epimeron. 



Pyrilloxenos compactus (Halictophagidae) furnishes the best op- 

 portunity for understanding the prosternal and mesosternal areas. 

 The eusternum is a narrow transverse piece. The sternellum is longi- 

 tudinally divided. Each side forms a half ring, composed also prob- 

 ably of precoxale and trochantin, between the points of which the 

 coxa is attached. This is the only presternum in which a distinct 

 pleural suture has been noticed. The episternum reaches the coxal 

 attachment in front of the suture and behind it the epimeron is di- 

 vided, reaching the coxa as hypoepimeron. The epimeron is slightly 

 visible above. Episternum is not visibly separated from the epinotum 

 (pi. 77, fig. 2). 



Anthericomma harberi (Halictophagidae) has a very interesting 

 prothorax. The pronotum is a circular disk completely inclosed by 

 the head and mesonotum. The pleural region is completely within 

 the mesopleurum. The sternum consists merely of two oval pieces 

 longitudinally separated, to which the coxae are attached, and at 

 each side of which appear parts of mesosternum. These two pieces 

 are the combined parts of sternellum, precoxale, and trochantin. 



In Delphacixenos anomalocerus (Halictophagidae) the pronotum 

 is even smaller than in the preceding species, and the prosternum is 

 similar!}^ reduced. 



In summary therefore we may describe the prothorax as a very 

 highly modified segment with the parts crowded and often fused. 



The prolegs are composed of a tiny coxa at the base of an elongate 

 trochanter, femur, tibia, and tarsus. In previous w^orks the coxa was 

 overlooked. Practically all the important variation is in the tarsus, 

 which is five-jointed with two claws in the Mengeoidea (pi. 64-66), 

 four-jointed without claws in the Xenoidea (pis. 69, 70, 72), three- 

 jointed in the Halictophagoidea (pis. 73-78), and two-jointed in 

 the Elenchoidea. In the Mengeoidea the first three joints are cylin- 

 drical, the fourth flattened with pulvillus, the fifth elongate with 

 pulvillus. In the Halictophagoidea the first joint is often very 

 broadly flattened, pulvillate, and the succeeding joints are narrower, 

 the last elongate (pi. 74, fig. 1). The femur and tibia are greatly 

 shortened and broadened in Pentozoe peradeniya and Dacyrtocara 

 oncometopiae (pi. 74, fig. 2). 



