48 WRIGHT AND MACALLUM. [Vol. I. 



nuclei, and fused protoplasm ; e, nuclei further elongated ; /, 

 stages in conversion of nuclei into ripe spermatozoa ; b, c,d,e X 

 590; a,fX 1000. 



Fig. 16. — From a sagittal series prepared with corrosive 

 sublimate ; u, upper, //, lower lip ; m, mouth ; pp, pre-, and 

 7np, muscular pharynx ; ai, anterior arch of intestine ; gs, 

 genital sinus ; be, bulbus ejaculatorius ; u, uterus without an 

 tgg', 5^r, shell-gland cells ; x 165. 



Fig. 17. — Cell of the vitellogen with corrosive sublimate ; a, 

 lobule of the vitellogen with Flemming's fluid ; X 650. 



Fig. 18. — Ovary from a Flemming's fluid preparation; a, 

 parietal cells; b, dividing cell; c, a ripe ovum; X 375- 



