SPERMATOGENESIS OF LEPISMA DOMESTICA 399 



Occasionally the lumen of the vas deferens is partially filled 

 with granules differing in size, and as the cells lining the vas 

 deferens may show similar granules in their cytoplasm, I have 

 considered the granular material of the lumen to be secretion 

 products of the cells. Although the bodies present" in the 

 seminal vesicle are a little longer than broad and show a little 

 difference in their size relations, yet I think they represent the 

 secretion found in the vas deferens. Munson ('06) considers 

 the epithelial cells of the vas deferens of the butterfly Papilio 

 to have a secretory function, but unfortunately he does not 

 figure or describe the process. 



An added fact of interest is that the bodies are transmitted 

 during copulation and are found in the seminal receptaculum 

 of the female, which suggests that they have some function yet 

 unknown to us. 



To ascertain their nature, smears of the seminal vesicle were 

 made, fixed in hot corrosive sublimate, and stained in orcein, 

 safranin and orange G, Delafield's haematoxylin and orange G, 

 safranin and malachite green, safranin and bleu de Lyon, Dela- 

 field's haematoxylin and erythrosin. In every case it was found 

 that the granules took only the cytoplasmic stains. In order to 

 test the possibility of the granules' being of a fatty nature, fresh 

 smears were stained in sudan III, but the result was negative. 

 Smears treated with ether showed also no effect of the latter on 

 the granules. 



When the spermatozoa are examined in the fixed and stained 

 condition (text fig. A and fig. 95), one finds a long chroma tin 

 staining thread ending in a transparent fine point, the acrosome 

 having disappeared, and extending from near the apex a con- 

 spicuous undulating membrane. The free edge seems formed of 

 a little denser material and represents in all probability the 

 proximal part of the axial filament, i.e., that part between the 

 acrosome and the middle-piece. 



It is almost impossible to see just where this membrane leaves 

 off distally as it gets narrower gradually, but I should say that 

 about the anterior tw r o-thirds of the spermatozoon is provided 

 with the membrane. It is not possible to find any trace of the 



