REFERENCES 251 



the cavernous tissue so that a relaxation occurs resulting in the 

 supplying of an unusual amount of blood to the venous sinuses. 

 The spaces of the cavernosa become engorged, so that the veins 

 emptying them are compressed to the point of interfering with the 

 outward flow of blood. Continued flow of blood into the sinuses 

 enlarges the corpora under pressure and results in making the penis 

 (juite rigid. After completion of spermatic discharge or passage of 

 excitement, the arterial walls regain their former tone, become 

 constricted, and the inflow of blood diminishes. The emptying of 

 cavernosa spaces is slowly effected; the j^enis slowly contracts and 

 becomes relaxed. 



REFERENCES. 



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Chase, S. W. 1923. The mesonephros and urogenital ducts of Necturus 

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Evans, T. C. 1930. Sex reversal in Rana pipiens, Anat. Rec, 48, 47. 



Hann, H. W. 1930. Variation in spermiogene.sis in the Teleost family, 

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Johnson, F. P. 1934. Dissection of human seminiferous tubules, Anat. 

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JuHN, M., AND Gu.ST.AVsoN, R. G. 1932. The response of a vestigial Mlillorian 

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McCuRDY, H. M. 1931. Development of the sex organs in Ti-iturus torosus. 

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Moore, C. R. 1926. The biology of the mammalian testis and scrotum. 

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Reese, A. M. 1924. The structure and development of the intromittent 

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Swift, C. H. 1916. Origin of the sex-cords and definitive spermatogonia in 

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TooTHiLL, M. C, AND YouNG, W. C. 1931. The time consumed by sperma- 

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See Appendix for general text references. 



