On Abortion in Coivs. 



67 



composition. They are contained in sacs called Graafian vesicles, 

 b b, fig. '2, which are surrounded by the substance or stroma of the 

 ovary, a a a. They consist, c c, of an outer part or wall containing 

 a quantity of fluid, within which floats a small body or nucleus, 

 e e. These minute ova are formed at an early period of life, but 

 onlv attain their full size or deve- 

 lopment when the female is of suf- 

 ficient age and size to propagate 

 her species. At this time, called 

 the period of puberty, the ripened 

 ova, fig. 3, approach and burst 

 through the surface of the ovary, c, 

 and pass to the uterus — a process 

 which takes place in the barren cow 

 at every period of heat, and is ac- 

 companied by a desire for sexual 

 intercourse with the male. If she 

 be allowed to have connection with 

 the bull, the male seed, by coming 

 in contact w4th the ovum or female 

 germ, establishes the condition of 

 conception. 



The fallopian tubes, or oviducts, 

 are two in number, — one, in con- 

 nection with each ovary, is situated 

 between the latter organs and the 

 uterus. They are, a a, fig. 4, very 

 tortuous, and are composed of a 

 tissue possessing contractile powers, 

 are lined by a soft moist membrane 

 largely supplied with blood at cer- 

 tain times, and externally they are 

 partially covered by peritoneum. Each tube opens into its re- 

 spective side of the uterus by a small orifice c ; the opposite end b is 

 much enlarged, or trumpet- 

 shaped, and is supplied with 

 a dense fringe of the same 

 kind of membrane which 

 lines its interior. The ends 

 last referred to are open ; 

 and, though indirectly at- 

 tached to, they float loosely 

 and slightly apart from the 



ovaries, except at periods of Diagram showing general form and direction of 

 - ' ^ . ^ Fallopian tube a «, with its expanded trumpet-shaped 



neat, when their trumpet- end b, audits narrow or uterine end c. d. Part of the 



shaped and fringed margins ^^'tionof Ovary. 



F 2 



Diagram showing magnified ripe Ovum 

 contained in its Graafian vesicle, lying close 

 upon the outside of the Ovary and just 

 within the Peritoneum, through which it is 

 ready to burst, a a, Substance of Ovary. 

 b b h, Graafian vesicle, composed of two 

 layers, c c c, Peritoneum, d, Ovum, con- 

 tained in its proper coverings, e e, Cellular 

 matter which forms round ripened Ova to 

 facilitate their passage from the Graafian 

 vesicles. 



