GENKRATIVK M'I'Mi I77X 



Fig. 404. 



a short, but very salient r- ru nnmlm inm. whieli divides into two HHH-OIIS cojnni'is. that 

 gradually subside po.-teriorly ; '_'. Towards the isch'al un-h, a vuhe \\h,^e free border, 

 dinvt.d downwards, covers a cnl-il -*< ab .lit :Mth.> to I im-li d< ep. 



Tlie structure of the urethra is also ditlereiit. Tli walls of (lie numbranoul portion 

 are thicker than in the Horse; they have a layer of erectile tissue, and a NVil^m'* 

 muscle, very thick below and laterally, mid whose fibres are insetted in the mid lie of 

 the upper surface, into an aponeurotic raphe'. 



At the ischial arch, when the caiml bends downwards, the spongy ti-sue l>e omes 



more abundant to form the lmll> f tin 

 \if flirn. ; but the prominence at this point 

 is chiefly due to the accelerator urina-. 

 us is shown in figure 404, c, 4. This 

 muscle is extremely powerful, but it 

 soon ceases beneath the ischial arch. 

 The traimvergus jterinei is as strong as in 

 Solipeds. 



Glands annexed to the urethra. 

 Cowper's glands are absent. The pro. 

 tate gland is not voluminous, and forms. 

 nt the commencement of the urethra, 

 a little transverse yellow mass, 1>< 

 which pass the vasa deferentia ; it al.-o 

 lies beneath Wilson's muscle, and is 

 prolonged for some distance on the mem- 

 branous portion of the urethra. 



Penis. In the Hull, the penis is long 

 and thin, and carried well forward be- 

 neath the belly. It is inclosed at the 

 perineum in an aponeurotic sheath. 

 which is covered by the ischio-tibinl 

 muscles. This sheath is double, its 

 superficial layer being continuous with 

 the dartos, and has the same physical 

 characters ; the deep layer is thin, white. 

 and inelastic. 



In front of the pubis, th" peirs <! B- 

 cribes two successive curves the 8 of 

 the penis the first with its convexity 

 forwards, the second back wards. It is 

 at the second curve that the suspensory 

 ligaments join the penis, and continue 

 along its sides to its extremity. 



The free portion of the organ, very 

 tapering, is covered by a line, papif- 

 lated, very sensitive, rose-colon nd 

 mucous membrane. 



It is lodged in a narrow sheath that 

 advances much more forward beneath 

 the abdomen than in Solipcds. and lias 

 at its opening a bunch of long stiff hairs. 

 This cutaneous sheath is moved by four 

 subcutaneous muscles : two posterior or 

 retractors (Fig. 405, 2) which draw the 

 sheath backwards, and concur in ex- 

 posing the penis at the moments of its 

 erection ; and two anterior or protractor 

 muscles (Fig. 405, 1) which carry the 



SECTIONS OF THE URETHB< OF THE OX AT 

 DIFFERENT POINTS. 



A, Intrapelvic portion ; 1, Wilson's muscle ; 2, 

 Erectile tissue; 3, Urethral canal ; 4, Prostate 

 gland. B, The middle of the penis ; 1, Fibrous 

 cord of the corpus cavernosum ; 2, Urethral 



canal; 3, Its erectile tissue; 4, Envelope of eheftth forwar " d to its former 



the corpus cavernosum. C, At the crura of t/u 

 penis ; 1, 1, Crura of the corpus cavernosum ; 

 2, Urethral canal; 3, Its erectile tissue; 

 4, Accelerator urina ; 5, Ischio-cavernosus 

 muscle. 



The j altcr ftre folln ,i in the 3^ ftnd do 

 not n p pear to be of any use. 



The two constituent portions of the 

 copulatory organ are not joined in the 

 same manner as in Solipeds, the channt 1 

 for the lodgment of the urethra being 

 transformed into a complete canal by n narrow layer of tho fibrous envelope of the corpus 



