THE ABDOMEN. 249 



Attached to the ovary is the Fallopian tube, a trumpet- 

 shaped organ, the anterior extremity of which presents a 

 very irregular margin, which is much jagged, and is 

 termed the jimhriated extremity or morsus diaholi. It is one 

 of the divisions of this extremity which connects it to the 

 ovary. It is perforated by a canal, which posteriorly gains 

 the- cavity of the uterus at a very small extremity in the 

 extreme anterior part of the horn of that organ. Ante- 

 riorly it dilates, opening into a peculiar serous sac of which 

 the ovary forms one boundary and which communicates on 

 one side freely with the main peritoneal cavity. The 

 ciliated epithelium with which it is lined is here replaced by 

 tessellated epithelium. This is considered remarkable as an 

 instance of a mucous membrane being directly continuous 

 with a serous membrane, but the histological distinction 

 between the two is insignificant. During sexual excite- 

 ment the fimbriated extremity is supposed to grasp the 

 ovary, approximating its anterior opening to the rupturing 

 Graafian vesicle. The tubes are convoluted, and present 

 muscular fibres of the unstriated class in their walls. 



The uterus is a large organ which occupies the anterior 

 part of the pelvis and the posterior part of the abdomen. 

 Its position, however, varies with its j^regnant or unim- 

 pregnated condition. Anteriorly it is bifid, presenting 

 two rounded sacs, the cornua or liorns. These meet at 

 an acute angle in the mare ; thus the equine uterus pre- 

 sents no fundus or space between the cornua. They open 

 into the body, which extends backwards to terminate in- 

 the nech, the portion running for a short distance into the 

 vagina to terminate at the os uterinum externum. The 

 oj^ening leading from the cavity of the body of the organ 

 to the passage of the neck is os uterinum internum. The 

 uterus is completely enveloped by peritoneum, being en- 

 closed in a double fold of that membrane, which on either 

 side extends to the supero -lateral parts of the abdomen, 

 forming the hroad ligaments of the uterus, on the free mar- 

 gin of which are the ovary, fallopian tube, and uterine 

 horn. Between the two layers of this ligament the round 

 ligament of the ovary runs from that organ to the extre- 

 mity of the horn of the uterus, from which point another 

 white fibrous (or muscular band) runs towards the internal 

 abdominal ring, where it becomes lost, the round liga- 

 ment of the uterus. The ovarian artery, after bemg 



