(E STRUM. 



57 



five organs at this.period become more or less turgid and sensitive, and 

 the uro-genital secretions are increased. In the female there is a deter- 

 mination of blood to the ovaries, and changes take place in these which 

 have already been described. The excitation of the generative apparatus 

 reacts on the whole system, and produces a kind of fever or irritability in 

 the animal ; its sensibility is increased ; the appetite is more or less in 

 abeyance or capricious, and usually there is thirst ; if the secretion of 

 milk has been previously active, it now diminishes, and in the non-impreg- 

 nated Bitch milk even appears in the mammae ; restlessness is a notable 

 feature, and the movements betray the prevailing desires. There is an 

 uncontrollable tendency to seek the opposite sex ; with some animals the 

 ordinary disposition becomes strangely perverted ; and in others again, 

 certain physical changes accompany the sexual perturbation. Attempts 

 at micturition in the female are frequent, but only a small quantity of 

 urine is passed j the mucous membrane of the vagina is injected ; and 

 with solipeds there are oft-repeated movements of the clitoris and vulva, 

 and an opaque white secretion, or even emissions of blood, are ejected 

 spasmodically /<?/- vulvam.* 



In other animals this ejection sometimes consists of a viscid, red- 

 tinted, or sanguinoient fluid. In all it has a special and powerful odor, 

 <which attracts the males, and enables them to distinguish between the 

 females which are in " rut " or " heat," and those which are not, as well 

 as exciting in them the most ardent amatory desires. 



The uterine mucous membrane is also very congested, and there is 

 poured out on its surface a fluid containing epithelial debris^ mucus cor- 

 puscles and blood globules. 



The existence in the lower animals of what is analogous to the men- 

 strual discharge in the human female, has frequently been deriied, but 

 without any reason or proof. A discharge of blood from the sexual organs 

 of woman announces the advent of puberty; and its coincidence with the 

 maturity and escape of the ovarian ovule, as well as its periodical appear- 

 ance until the termination of fertility, establishes between this phenome- 

 non and the " heat " or " rut " {oestrum) of animals a very close analogy. 

 And this analogy is rendered complete by the fact that animals also at 

 this period have more or less evident sanguine emissions. Kahleis, 

 Fuchs, Spinola, Numann, and others have observed this in the Cow, and 

 have also noted that the discharge occurs regularly at intervals of nine- 

 teen or twenty days when the animal is not giving milk or in calf. The 

 haemorrhagic flow appears two or three days after the commencement of 

 " rutting," and when this is most intense. The amount of blood does 

 not exceed one or two ounces, and the coagulated clot remains in the 

 vagina until it is expelled with the urine. There can be no doubt as to its 

 source. If, at the moment when traces of it are perceived externally, the 

 Cow is killed and the inner surface of the uterus examined, blood will be 

 seen exuding from the cotyledons. And this phenomenon has been 

 proved to extend beyond the bovine species, for it has been witnessed 

 in the Mare, Bitch, Cat, Rabbit, etc. ; and in the red-colored mucus of 

 the vagina and uterus, multitudes of blood-corpuscles have been found. 



The cause of menstruation or periodical discharges of blood in female 

 animals, has received a satisfactory explanation from the researches of 



* Kaiser, in the Magazin/nr die gesammte Thierheilkunde for 1859, mentions a Mare, twentj'-four 

 years of age, which every three weeks had a sanguineous emission from the vulva ; this discharge ceased 

 towards the middle of pregnancy, but returned after parturition. I have frequently witnessed the periodic 

 discharge from Mares either streaked with blood, or blood-tinted. 



