DISSECTION OF THE PELVIS. 355 



of the expansion is smooth and covered by peritoneum. The uterine 

 extremity of the tube opens into the extremity of the uterine liorn by a 

 minute orifice — the ostium uterinum. 



Although the Fallopian tube bears to the ovary the relationship of an 

 excretory duct, in that it conveys away the ova, it differs from all other 

 excretory ducts in not having its lumen closely continuous with the 

 interior of the gland whose secretion it conveys. Moreover, this discon- 

 tinuity between the Fallopian tube and the ovary establishes an indirect 

 communication between the sac of the peritoneum and the surftice of the 

 body, and brings about the single exception to the rule that serous 

 membranes form perfectly close sacs. 



Structure of the Tube. The wall of the oviduct comprises the follow- 

 ing layers, enumerated from without inwards, viz., (1) an outer serous coat, 

 derived from the broad ligament ; (2) a coat of non-striped muscular tissue, 

 arranged as an outer longitudinal and an inner circular set of fibres; (3) 

 a submucoiis coat of vascular connective-tissue ; (4) a mticous coat, having 

 a ciliated columnar epithelium. 



The lumen of the tube is narrowest at its uterine extremity and widest 

 at the ovary. 



The Uterus, or womb, is the organ that receives the ovum, retains it 

 during its development (provided it has been fertilised), and, finally, 

 expels it at the expiration of the full term of pregnancy. In situation 

 the oi'gan is partly abdominal, and partly pelvic, and its mode of 

 suspension by the broad ligaments has already been observed in 

 connection with the peritoneum (page 303). 



The organ is single in its posterior portion, and bifid in front. 



The anterior bifurcations of the organ are termed its cornua or horns. 

 At its anterior extremity each horn is pointed, and receives the uterine 

 opening of the Fallopian tube. From this point the calibre of the horn 

 gradually increases to its posterior end, where it opens into the body of 

 the organ. Each horn shows a concave upper border at which the broad 

 ligament reaches it, while its lower border is convex and free. The 

 cornua are entirely abdominal in position, and are related to the 

 intestines. 



The posterior single portion of the uterus comprises the body, and the 

 neck, or cervix; but this division is not apparent on the exterior. 



The body, placed in front, presents two faces, two borders, and two 

 extremities. The upper face is slightly flattened and related to the 

 rectum ; the lower fiice, also flattened, is related to the intestines in 

 front, and to the bladder behind ; the borders, right and left, show the 

 insertions of the broad ligaments; the anterior extremity, or fitndus, is 

 the widest part of the body, and it is joined at each angle by the cornu ; 

 the posterior extremity is continuous with the cervix. The body of 

 the uterus is partly abdominal and partly pelvic in situation. 



