178 Journal New York Entomological Society. [Voi. xi. 



nous area. Two long, slender, blade-like processes (Figs. 5, 7, 9 and 

 10, a) arise from its posterior end and project backwards. They are 

 almost as long as the sternum itself and are set on edge side by side. 

 The space between the dorsal surface of the eighth sternum and the 

 ventral surfaces of the ninth and tenth segments is the genital cham- 

 ber. Arising from the floor of this chamber, /. e., from the dorsal 

 surface of the projecting part of the eighth sternum, is a small darkly 

 "chitinized plate (Fig. 8) ending posteriorly in two free diverging 

 >prongs. This plate may be the fused and rudimentary anterior 

 igonapophyses. 



The ninth segment (Figs. 5, 7, 9 and 10, IX) is very small. Its 

 tergum consists of a narrow transverse band of chitin back of the 

 eighth tergum. The ventral part of the ninth segment is entirely 

 hidden above the eighth sternum. It is membranous and is contin- 

 uous with the membranous ventral surface of the tenth segment. 

 The two together form the roof of the genital chamber. In this mem- 

 brane are two chitinous rods that arise close to the lower ends of the 

 ninth tergum (Fig. 2) and converge posteriorly where they unite in 

 a chitinous plate ending in two free prongs on the under side of the 

 tenth segment. The two free processes are apparently the rudimen- 

 tary second gonapophyses. The plate and converging arms may be 

 regarded as the ninth sternum. 



The tenth segment (Figs. 5, 7, 9 and 10, X) is relatively large. 

 Its dorsum is convex and presents a number of transverse wrinkle-like 

 grooves. Its basal part is widest, the median part somewhat con- 

 tracted, and the terminal part is slightly expanded again into a trian- 

 gular suranal plate. The membranous ventral part is slightly con- 

 cave. It terminates in two rounded podical plates. On each side a 

 long, rigid, tapering, chitinous cercus (Figs. 5, 7, 9 and 10, cer.') 

 arises between the suranal and podical plates. 



Tipula bella Loe^o. (PI. X, Fig. 6.) 



Externally this species scarcely differs from T. angiistipennis. 

 The lower ends of the ninth tergum are wider (Fig. 6, IX t.). The 

 ninth sternum consists of two triangular plates, each with a long 

 tapering angle projecting posteriorly and inwardly (Fig. 6, gon. 2). 

 The first gonapophyses are slenderer than in the last species, and the 

 podical plates are shorter. 



