DESCRIPTIONS OF GENERA AND SPECIES. 281 



tibiae of the first two pairs of legs; a short, thick, 

 curved hair on each genual of the first pair and each 

 tibia and genual of the second pair of legs, and a few 

 fine hairs on the various joints. Claws and caroncles 

 as in the adult. 



The Hypopial Nymph (PL XVI, fig. 5, and PI. 

 XVII, fig. 7). 



Length about .... . '25 mm. 



Breadth about . . . . . . "15 



Length of legs, all pairs, about . . . '09 



Colour yellowish white ; legs and posterior end of 

 abdomen reddish. Texture polished : slight granula- 

 tion shows through the semi-transparent chitin. Hood 

 of rostrum narrow and drawn out, much more so than 

 in Kramer's original drawing ; the two ordinary labial 

 hairs of a hypopus short and wide apart. Behind the 

 rostrum the cephalothorax is large and wide ; it has 

 strongly curved lateral edges, and a posterior outline 

 slightly convex backward. The abdomen is slightly 

 broader than its length ; concave anteriorly ; sharply 

 divided from the cephalothorax; it has a strongly 

 rounded outline both laterally and posteriorly ; on the 

 posterior margin, however, are two projecting points 

 some short distance from the median line ; the outline 

 between them is concave ; these points and concavity 

 are produced by the apparatus on the ventral surface 

 for holding the hairs of the host. Notogaster arched, 

 without hairs or markings ; there are, however, a pair 

 of very short hairs, or spines, near the antero -lateral 

 angles of the abdomen, and two similar pairs on the 

 posterior margin near the points. The expulsory 

 vesicles show plainly at the edge of the abdomen, about 

 one-third of its length from posterior end. The legs 

 are of moderate length ; the fourth pair scarcely pro- 

 ject further back than the posterior margin. The two 

 anterior pairs are much thicker than the posterior ; they 

 have large tactile hairs, and two or three fine curved 



