240 THE PHYSIOLOGY OF REPRODUCTION 



(in the human subject) are about two inches below the openings 

 of the vasa deferentia. The lobules of the glands are surrounded 

 by a firm investing membrane which contains muscular tissue. 

 They are lined internally by a secretory epithelium. 



The significance of the viscous secretion which these glands 

 produce is still unknown. It has been suggested that it serves 

 to cleanse the urethra of urine or semen. Since it is poured out 

 in considerable quantity during coitus, and appears sometimes 

 to precede the ejaculation of the actual semen, it is not im- 

 possible that the secretion of these glands may possess the 

 special function of ridding the urethra of all traces of urine 

 preparatory to the passage of the spermatozoa. The glands of 

 Littre or Morgagni, which beset the whole lining membrane of the 

 urethra, except near the external orifice, probably serve the same 

 purpose as Cowper's glands. (Cf. prostate, footnote 3 , p. 236.) 



According to Nagel, 1 Cowper's glands are of the normal 

 dimensions in castrated men, and consequently should not be 

 regarded as purely sexual organs. On the other hand. 

 Schneidemiihl, 2 whom Nagel quotes, says that in animals 

 they atrophy after castration. Griffiths 3 describes these 

 glands in the hedgehog and the mole as undergoing periodic 

 changes similar to those of the prostate glands. In the hedge- 

 hog the secretion is abundant during the summer (i.e. in the 

 breeding season), and possesses a disagreeable and penetrating 

 odour. According to Gley, 4 the secretion in this animal contains 

 a ferment which causes the fluid of the vesiculse seminales to 

 clot, so that Cowper's glands in the hedgehog are the physio- 

 logical equivalent of the prostate gland in the Rodentia. 5 



1 Nagel, " Physiologie der Miinnlichen Geschlechtsorgane," NageVa Hand- 

 buck der Physiologie des Menschen," vol. ii., Braunschweig, 1906. 



2 Schneidemiihl, " Vergleichende Anatomische Untersuchungen iiber 

 denfeineren Bau der Cowperschen Druse," Deutsche Zeitschr. f. Tiermedizin, 

 vol. vi., 1883. 



* Griffiths, " Observations on the Function of the Prostate Gland," &c., 

 Jour, of Anal, and Phys., vol. xxiv., 1890. 



4 Gley, "Role les Glandes genitales accessoires dans la Reproduction," 

 Nel primo Centenario dalla Morte di Lazzaro Spallanzani Acad. Sci. e 

 Stranieri, 1899. 



8 It should be mentioned that very considerable doubt has been thrown 

 on the homology of what are often called Cowper's glands (those presumably 

 referred to by Gley and Griffiths) in the hedgehog with the glands known 

 by that name in other Mammals. According to Leydig (" Zur Anatomie der 



