6 4 



occurs from the outside toward the lumen of the seminiferous 

 tubules, so that in the innermost layer would be found maturing 

 (or mature) spermatozoa, in the outermost layer spermatogonia 

 (parietal cells), and between spermatocytes (mother cells) and 

 spermatids (daughter cells), which metamorphose into the sperma- 

 tozoa. Find also the supporting cells (Sertoli cells) and observe 

 their relation to the ripening spermatozoa. 



142. Spermatozoa. Cat. Dried on the cover glass. No 

 staining. Mount on a shellac ring ( 103, a). 



Recognize the three parts head, middle-piece, and tail, noting 

 the shape and relative length of each ; compare with the sperma- 

 tozoa found in the tubules and ducts (vasa) in 139, 141, noting 

 the staining reactions of the parts. 



VAS DKFKRENS. 



143. Vas deferens. . ; paraffin ; sec- 

 tions yu. Stain with hematoxylin and 



Determine the number oi the coats and their structure ; the 

 course of the fibers in the muscular layers and the character of the 

 epithelium, and compare it with the epithelium found in the tubules 

 of the epididymis. 



PROSTATE GLAND. 



144. Prostate. . Transection of the gland and ure- 

 thra. ; collodion ; sections yu. Stain with hema- 

 toxylin and eosin. 



Understand the relation of the gland, to the bladder and the ure- 

 thra. In the section, observe the relation of the gland mass to the 

 urethra. Is a division into lobes indicated ? Note the capsule and 

 its structure, the acini and ducts forming the gland mass, together 

 with connective tissue and plain muscle. Does the section include 

 the prostatic sinus or the ejaculatory ducts (vasa deferentia) ? 



