REPRODUCTION. 



655 



CORPUS LUTEUM OF MENSTRUATION. CORPUS LUTEUM OF PREGNANCY. 



At the end of 



weeks. 

 One month. 



Two months. 

 Four months. 

 Six months. 

 Nine months. 



three | Three-quarters of an inch in diameter ; central clot reddish ; 

 convoluted wall pale. 



Smaller; convoluted 

 wall bright yellow ; clot 

 still reddish. 



Reduced to the condition 

 of an insignificant cicatrix. 



Absent or unnoticeable. 



Absent. 



Absent. 



Larger ; convoluted wall bright 

 yellow ; clot still reddish. 



Seven-eighths of an inch in 

 diameter ; convoluted wall bright 

 yellow ; clot perfectly decolorized. 



Seven-eighths of an inch in 

 diameter ; clot pale and fibrinous; 

 convoluted wall dull yellow. 



Still as large as at the end of 

 second month ; clot fibrinous ; 

 convoluted wall paler. 



Half an inch in diameter ; cen- 

 tral clot converted into a radiating 

 cicatrix ; external wall tolerably 

 thick and convoluted, but without 

 any bright yellow color. 



THE REPRODUCTIVE ORGANS OF THE MALE. 



The reproductive organs of the male comprise the testicles, vasa 

 deferentia, vesiculae seminales, and penis. 



The Testicles. The testicles are oblong glands, about 40 mm. in 

 length, 30 mm. in breadth and 20 mm. in 

 thickness, and contained within the cavity 

 of the scrotum. A section of the testicle 

 (Fig. 321) reveals the presence externally 

 of a dense fibrous membrane, the 

 tunica albuginea, and internally a con- 

 nective - tissue framework consisting 

 mainly of septa, which enter the organ 

 on its posterior aspect at the mediastinum 

 testis, passing inward in a diverging 

 manner. The spaces between the septa 

 are occupied by the true gland substance, 

 the seminiferous tubules. 



The seminiferous tubules are very 

 numerous, the estimate as to their 

 number varying from 800 to 1000. 

 When unraveled they measure from 30 

 to 40 cm. in length and 0.3 mm. in 

 diameter. At their peripheral extrem- 

 ities the tubules are very much con- 

 voluted, but as they pass toward the 

 mediastinum testis, the convolutions 

 disappear, and after uniting with one another terminate in from 

 twenty to thirty straight tubes, the vasa recta, which pass through 



FIG. 321. DIAGRAM OF A VER- 

 TICAL SECTION THROUGH A 

 TESTICLE, i. Mediastinum 

 testis. 2, 2. Trabeculae. 

 3. One of the lobules. 4, 4. 

 Vasa recta. 5. Globus ma- 

 jor of the epididymus. 6. 

 Globus minor. 7. Vas def- 

 erens. (H olden.) 



