THE OVARIES 



597 



The weight is about two and a half to three 



C^- 



and a half (ca. 3-4 cm.) thick, 

 ounces (ca. 70-80 grams). 



Each presents for description two surfaces, two borders, and two extremities. 

 The surfaces are termed medial and lateral (Facies medialis, lateralis) ; they are 

 both smooth and rounded.^ The attached or mesovarial border (Margo mes- 

 ovaricus) is convex. It is enclosed in a part of the broad ligament termed the mes- 

 ovarium; the vessels and nerves reach the gland at this border. The free border 

 (Margo liber) is marked by a notch which leads into a narrow depression, the 

 ovulation fossa. The tubal or anterior extremity (Extremitas tubaria) is rounded, 

 and is related to the fimbriated end of the uterine 

 tube. The uterine or posterior extremity (Extremitas 

 uterina) is also round, and is connected with the horn 

 of the uterus by the ovarian ligament. 



The ovaries are situated in the sublumbar region, 

 and are usually ventral to the fourth or fifth lumbar 

 vertebra. They are usually in contact with the lum- 

 bar wall of the abdomen. The average distance from 

 the ovaries to the vulvar orifice is about twenty to 

 twenty-two inches (ca. 50-55 cm.) in a mare of 

 medium size. 



The position of the ovaries is very inconstant, as might 

 be expected from their mode of attachment. Either ovary or 

 both may be deflected transversely ia either direction to the 

 full limit allowed by the mesovarium. The so-called medial 

 and lateral surfaces are usually dorsal and ventral, or vice 

 versa, according to the direction of the deflection. The range 

 of variation in the longitudinal direction is greater than was 

 formerly thought to be the case. The right ovary is often 

 about six inches (ca. 15 cm.) behind the corresponding kid- 

 ney, but the distance between them may be nearly twice as 

 great or may be only about two inches (ca. 5 cm.). The left 

 ovary is usually a little (ca. 2-3 cm.) further back than the right 

 one, but is usuaUy nearer the corresponding kidney, the average 

 distance between them being about four inches (ca. 10 cm.). 

 They may be about two inches (ca. 5 cm.) from the extremity 

 of the corresponding cornu of the uterus or in contact with it. 

 Except during pregnancy, they are almost always in contact 

 with the lumbar abdominal wall, and do not hang down among 

 the adjacent viscera. 



Fig. 531. — Right Ovart of Mahb, 

 WITH Adjacent Structures. 

 The extremity of the cornu is 

 opened. 1, Ovary; 1\ corpus luteum; 

 2, uterine or Fallopian tube, with its 

 ostium abdominale {2'), fimbriae {2"), 

 and ostium uterinum {2'") ; 3, cornu 

 uteri with its mucous lining {3') ex- 

 posed; 4. ligament of ovarj^; 4', naeso- 

 salpinx. {.\fter Ellenberger, in Leiser- 

 ing's Atlas, reduced.) 



The ovary is attached to the sublumbar region 

 by the anterior part of the broad ligament of the 

 uterus; this part of the ligament, the mesovarium, 

 is about three or four inches (ca. 8 to 10 cm.) wide, 

 measured from the ovary directly to the parietal at- 

 tachment. The uterine extremity of the ovary is 

 coimected with the extremity of the cornu of the 

 uterus by the ligament of the ovary (Lig. ovarii pro- 



prium) ; this is a band of unstriped muscle enclosed between the layers of the broad 

 ligament. 



Structure. — The greater part of the surface of the ovary has a covering of 

 peritoneum. The peritoneal investment is absent at the attached border where 

 the vessels and nerves enter; this area is termed the hilus of the ovary (Hilus 

 ovarii), although there is no depression here. The ovulation fossa is covered by 

 a layer of short polygonal cells, a remnant of the primitive germinal epithelium. 



1 These terms apply properly only when the adjacent viscera are removed and the ovaries 

 are actually "suspended" by the broad ligaments. When the ovary is in its natural position, 

 the surfaces are usually dorsal and ventral, the former corresponding to the "lateral" surface if the 

 free border is directed outward, to the "medial" if the free edge is medial. 



