1068 URINARY AND REPRODUCTIVE ORGANS 



pudic nerves, accompany the arteries; each nerve gives off filaments to the deep 

 transversus perini^i, and tlien pierces the fore part of the superficial triangular 

 ligament Avith the dor.-^al artery. 



(7) The deep transversus perinaei, compressor urethrae, or muscle of 

 Guthrie. — The muscular tissue of the deej) perinatal space has l)een a source of 

 great confusion owing to the multiplicity of the names which liave been assigned 

 to various portions of it; but the description given ])y Henle may ])o accepted as at 

 once the simi)lest and the most accurate. The transversus perinaei profundus 

 of Henle is closely connected with the superior and inferior triangular ligaments. 

 It arises from the inner surface of the ischio-pubic ranuis, by tendinous bundles 

 which separate to form a kind of channel for the pudic vessels and dorsal nerve of 

 the penis, close to the bone. From this origin the greater part of the fibres run 

 across the subpubic angle in a transverse direction in front of and behind the mem- 

 branous urethra, enclosing Cowper's glands and the deep veins of the penis, and 

 join a more or less indistinct median raphe; while others pass more or less 

 obliquely forwards in front of the urethra and behind the dorsal vein to become 

 attached to the pubic ramus on the side opposite to the bony attachment. A small 

 accessory bundle (the ' sagittal layer ' of Henle) may sometimes be found running 

 directly forwards to become inserted into the upper surface of the bull) and into 

 the connective tissue between the corpora cavernosa; and the name ' muscle of 

 Wilson ' has been given to a few fasciculi, often difficult to demonstrate, running 

 from the subpubic ligament to the membranous urethra. 



The arrangement of the fibres differs considerably in different sul)jects, and 

 much complexity has l^een introduced into the study of the muscle by the artificial 

 segregation of certain of its parts under special names, such as levator vn-ethra3, 

 constrictor urethra, etc. 



Its action is partly to compress the membranous urethra and thus assist the 

 expulsion of urine and semen, and partly to intercept the flow of blood through 

 the veins of the penis, and so aid in erection. It also exercises compression 

 upon Cowper's glands, and effects the discharge of their secretion during seminal 

 emission. It is supplied by a branch from the dorsal nerve of the penis. 



The deep or superior triangular ligament (figs. 650, 652, 654) is in some sort 

 a prolongation of the obturator fascia across the pubic arch, the continuity of the 

 two fasciae, however, l?eing interrupted b}' the attachment of their deep fibres to 

 the inner edges of the ischio-pul:)ic rami. Inferiorly it is in intimate relation with 

 the deep transversus perinaei; while superiorly it forms on each side the floor of 

 the anterior extension of the ischio-rectal fossa; and in the middle line it is sepa- 

 rated from the apex of the prostate by a prolongation of recto-vesical fascia, and l)v 

 a layer of smooth muscular fibre, the prerectalis of Henle, in which end the 

 greater part of the anterior longitudinal filires of the rectum. 



It is pierced by the pudic artery and vein and the dorsal nerve of the penis. 

 The dorsal vein of the penis passes between it and the subpubic ligament. 



THE FEMALE PERINEUM 



The female perinaeum (fig. 656) differs from that of the male, partly in the 

 perforation of the whole of its fascial and muscular structures in the middle line by 

 the vulvo-vaginal passage, and partly in the adaptation of the perinatal muscles to 

 the modified conditions of the external genital apparatus. The corpora cavernosa 

 penis are represented by the relatively diminutive corpora clitoridis ; the ischio- 

 cavernosi are proportionately reduced in size, but differ in no otlier material respect; 

 the cor))US spongiosum is divided into two lateral segments, which are represented 

 by the bulbi vestibuli and partes intermediales ; and the two Inilbo-cavernosi 

 are sc])arate, and ajipear in an atteininted form. s]n-ead over the erectile tissue as 

 an attenuated plane of filjres, the compressor vaginae, which is often difficult to 

 recognise on dissection; while the meilian ra])he uniting tlie two nniscles in the 

 male gives place to the genital fissure. Tlie superficial transversi perinaei 

 differ only in size from those of tlie male; 1)ut the deep transversus perinaei is 

 of course cleft by the vagina, and its fil)res are relatively thin and weak and in 



