446 



LABORATORY MANUAL OF HUMAN ANATOMY 



attachment of the deep layer? Does it acquire smooth muscle 

 fibres in the labium majus to form a tunica dartos ? Study 



Arteries. 



(a) Artery of perineum (A. perinei). Trace this artery forward to 



the labia majora and dissect out 

 (aa) Posterior labial arteries (Aa. labiales posteriores) . 



Look for a small artery passing into the superficial transverse 

 muscle of the perineum, the " transverse perineal artery." 

 Nerves. (Fig. 232.) 



FIG. 231. 



Urethra 



Vagina 



Corpus cavernosum urethrae 



Venous plexus . ^ 



"" 



Columna ant. 



....Columnapost. 



Corp. cav ----- > 

 clit. 



Clitoris 



--Rectum 



Praeputium 

 clitoridis 



M. sph. ext. 



Foss. navic. 



Labium minus' 



Hymen (femininus) Frenulum lab. pud. 



Sagittal section through the vulva and vagina to show the lateral walls of the vestibule. (From 

 Poirier et Charpy, Traite d'Anat. hum., Paris, 1901, t. v. p. 558, Fig. 382.) 



(a) Nerve of perineum (N. perinei). 



(aa) Posterior labial nerves (Nn. labiales posteriores). 



(b) Perineal branches of posterior cutaneous nerve of thigh (0. T. 



small sciatic). 

 Lymphatics. 



Determine the course of the lymphatics found in this region, 

 also the lymph-nodes with which they communicate. (Vide 

 Toldt, Fig. 1093.) 



Remove this fascia and expose to view the contents of the 

 " superficial perineal compartment " (between fascia perinealis 

 and diaphragma urogenitale). (Cf. Figs. 227, 229.) 



Clean off the fascia from the muscles, determine the form, 

 position, origin, insertion, action, and nerve-supply of the fol- 

 lowing : 



Muscles. (Vide Spalteholz, Fig. 669.) 



(a) Superficial transverse muscle of perineum (M. transversus perinei 

 superficialis) . This muscle is not constant. It is found in the 

 female in a little more than thirty per cent, of the cases. In the 

 male it is more frequent. 



