JOURN.^L 



J}f\a JBopk ^Intomologiral HcriFfg, 



Vol. XT. DECEMBER, 1903. Ko. 4 



THE TERMINAL ABDOMINAL SEGMENTS OF 

 FEMALE TIPULID^. 



By Robert E. Snodgrass. 

 (Plates X and XI.} 



In a paper not yet published -i^ the writer has described and figured 

 the terminal parts of the male abdomen for a large number of Tipulid 

 species. The present paper is complementary to this one for the 

 same species have been used in studying the female abdomen. The 

 specimens were identified by Mr. R. W. Doane and belong to the zoo- 

 logical department of the Washington Agricultural College. 

 Tipula angustipennis Log7C'. (PI. X, Figs. 2, 5, 7, 8, 9 and 10.) 



This species will be described first as an example of the entire 

 family. 



The abdomen (Fig. 10) is long and slender, slightly swollen at 

 the fourth and fifth segments. Posteriorly it terminates in a slender 

 tapering point when the apical parts are appressed. There are ten 

 abdominal segments. The first seven have the ordinary cylindrical 

 shape. The eighth, ninth and tenth are the ones that present the 

 genital modifications. 



The eighth tergum (Figs. 5, 7, 9 and 10, VIII t^ is only about 

 a third of the length of the seventh tergum. It is otherwise unmodi- 

 fied. The eighth sternum {VIII s) on the other hand, is greatly 

 elongate, reaching far beyond its tergum. It is strongly convex ven- 

 trally and projects posteriorly beneath the ninth and tenth segments. 

 On the posterior half it presents a long median triangular membra- 



*The Hypopygium of the Tipulidx (MS.), Proc. Davenport Acad. Sci. 



