214 



JOSE F. NONIDEZ. 



epithelium is highly modified, the thin cuticular lining being 

 much thicker and thrown into a few very distinct ridges (Fig. 4, 

 c). The anterior end of the uterus forms a pouch (Fig. 5, 01) 

 capable of great distension ; its walls are thrown into irregular 

 foldings which in sections appear as papillae. The oviduct opens 

 dorsad to this pouch by a wide opening (Fig. 5, d}. 



The female of Drosophila differs from that of most of the 

 other flies in the presence of an unpaired seminal receptacle 



FIG. 5. Sagittal section of the anterior portion of the uterus in a virgin fly. 

 a, anterior pouch ; d, oviduct ; p, duct of one of the parovaria with p', its 

 opening in the dorsal wall of the uterus; s, duct of one of the spermathecae, 

 with s', its opening into the uterus ; u, uterine cavity ; v, ventral receptacle 

 with v' , its opening into the uterus. 



placed in the ventral surface of the uterus (Fig. 3, v) and by the 

 existence of two smaller receptacles or spermathecae (s}. Occa- 

 sionally three spermathecae occur and this condition seems to be 

 normal in many of the diptera (Berlese, 1909). 



The spermathecae (Figs. 3 and 9, j) open into the dorsal wall 



