FASCLE OF THE UPPER EXTREMITY. 271 



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Between the two layers of the deep perineal fascia are situated, there- 

 fore, the whole extent of the membranous portion of the urethra, the com- 

 pressor urethrse muscle, Cowper's glands, the internal pudic and bulbous 

 arteries, and a plexus of veins. Mr. Tyrrell considers the anterior lamella 

 alone as the deep perineal fascia, and the posterior lamella as a distinct 

 layer of fascia, covering in a considerable plexus of veins. 



FASCIJE OF THE UPPER EXTREMITY. 



The superficial fascia of the upper extremity contains between its layers 

 the superficial veins and lymphatics, and the superficial nerves. 



The deep fascia is thin over the deltoid and pectoralis major muscles, 

 and in the axillary space, but thick upon the dorsum of the scapula, where 

 it binds down the infra-spinatus muscle. It is attached to the clavicle, 

 acromion process, and spine of the scapula. In the upper arm it is some- 

 what stronger, and is inserted into the condyloid ridges, forming the in- 

 termuscular septa. In the fore-arm it is very strong, and at the bend of 

 the elbow its thickness is augmented by a broad band, which is given off 

 from the inner side of the tendon of the biceps. It is firmly attached to 

 the olecranon process, to the ulna, and to the prominent points about the 

 wrist. Upon the front of the wrist it is continuous with the anterior annu- 

 lar ligament, which is considered by some anatomists to be formed by the 

 deep fascia, but which I am more disposed to regard as a ligament of the 

 wrist. On the posterior aspect of this joint, it forms a strong transverse 

 band, the posterior annular ligament, beneath which the tendons of the 

 extensor muscles pass, in distinct sheaths. The attachments of the pos- 

 terior annular ligament are, the radius on one side, and the ulna and pisi- 

 form bone on the opposite side of the joint. 



The tendons, as they pass beneath the annular ligaments, are surrounded 

 by synovial bursse. The dorsum of the hand is invested by a thin fascia, 

 which is continuous with the posterior annular ligament. 



The palmar fascia is divided into three portions. A central portion, 

 which occupies the middle of the palm, and two lateral portions, which 

 spread out over the sides of the hand, and are continuous with the dorsal 

 fascia. The central portion is strong and tendinous : it is narrow at the 

 wrist, where it is attached to the annular ligament, and broad over the 

 heads of the metacarpal bones, where it divides into eight slips, which are 

 inserted into the sides of the base of the first phalanx of each finger. The 



abdominal parietes. 4. The ureter. 5. The vas deferens crossing the direction of the 

 ureter. 6. The vesicula seminalis of the right side. 7, 7. The prostate gland divided 

 by a longitudinal section. 8, 8. The section of a ring of elastic tissue encircling the 

 prostatic portion of the urethra at its commencement. 9. The prostatic portion of the 

 urethra. 10. The membranous portion, enclosed by the compressor urethra muscle. 

 It. The commencement of the corpus spongiosum penis, the bulb. 12. The anterior 

 ligaments of the bladder, formed by the reflection of the pelvic fascia, from the internal 

 surface of the os pubis to the neck of the bladder. 13. The edge of the pelvic fascia at 

 the point where it is reflected upon the rectum. 14. An interval between the pelvic 

 fascia and deep perineal fascia, occupied by a plexus of veins. 15. The deep perineal 

 fascia; its two layers. 16. Cowper's gland of the right side, situated between the two 

 layers below the membranous portion of the urethra. 17. The superficial perineal 

 fascia, ascending in front of the root of the penis to become continuous with the dartos 

 of the scrotum (18). 19. The layer of the deep fascia which is prolonged to the rectum. 

 20. The lower part of the levator ani ; its fibres are concealed by the anal fascia. 21. 

 The inferior segment of the funnel-shaped process given off from the posterior Inyer of 

 the deep perineal fascia, which is continuous with the recto-vesical fascia of Tyrrell. 

 The attachment of this fascia to the rectovesical'fold of peritoneum is seen at 22 



