REPRODUCTION IN DROSOPHILA. 



213 



They contain a dense, sticky fluid in which float abundant re- 

 fractive granules of unequal size. This fluid is mixed with the 

 spermatozoa at their entrance into the vas deferens and forms 

 the liquid part of the ejaculate. 



Female. 



The ovaries (Fig. 3, o) are connected by means of short paired 

 oviducts (d) with a single azygos oviduct (cf ) which opens in 

 the anterior end of the uterus () The latter is a sac with 

 highly muscular walls, lined internally by an epithelium of cubical 



FIG. 4. Cross section of the vagina, showing the irregular lumen and the 

 papillae in which the epithelium is thrown, b, basal portion of the epithelium 

 containing the nuclei ; e, fibrillar portion ; c, cuticle. 



cells, which secretes a thin cuticle. Two distinct regions can be 

 recognized in this organ: a distal region or uterus proper (Figs. 

 3 and 9, u] and a proximal region or vagina (M') in which the 



