THE HORSE. 



127 



of the abdomen : they receive close cov- 

 erings, and are loosely attached to the 

 spine. 



These bodies are about the size of v^al- 

 nuts. They are not regular oviform ; they 

 have deep fissures on their sides ; they 

 bear a resemblance, at first view, to the 

 testicles and their ducts in the male. 



Internally, the ovaries are composed of a 

 whitish spongy substance, in which are, in 

 some instances, found little vesicles, con- 

 taining a yellowish glairy fluid, in others 

 one or more dark yellow or brownish sub- 

 stances, named corpora lutea : the vesicles 

 are the ova, which, from impregnation, re- 

 ceive further development; the corpora 

 lutea denote the parts from which vesicles 

 have burst, and consequently only exist in 

 the ovaries of those mares whose organs 

 have been engaged in the generative pro- 

 cess. Prior to the age of sexual intercourse, 

 these bodies are small and white ; but, as 

 soon as the season of copulation is at hand, 

 they grow large, redden externally, and 

 present many yellow spots or streaks 

 through their substance. 



Mammce, though unconnected with the 

 uterus, anomatically speaking, are in func- 

 tion concurring to the same important end. 

 The mammae, vulgarly called udder, are 

 two flattened oval-shaped bodies, depend- 

 ing, between the thighs, from the posterior 

 and inferior part of the belly. In quadru- 

 peds, with but few exceptions, this is the 

 situation of the mammas. 



In virgin mares the udder is so small 

 that there hardly appears to be any. In 

 mares who have had foals, the udder re- 

 mains prominent or pendulous, and has a 

 flabby feel. 



Toward the latter part of gestation, this 

 part swells, and becomes distinctly visible. 

 Within a few days of foaling, the udder 

 grows turgid with milli ; it does not, how- 

 ever, acquire its full distention until the 

 foal has drawn it for a few days, from 

 which time it maintains its volume, with 

 little variation, during the period of suck- 

 ling. Soon after the foal begins to forsake 

 the teat, the secretion of milk diminishes, 

 and is followed by a contraction of the 

 bag, which goes on gradually, until it has 

 resumed nearly, or quite, its former flat- 

 ness. 



The interior of the mammae has a fight 

 yellowish aspect, and evidently possesses a 

 lobulated structure, which is held together 

 by a fine cellular tissue, interspersed with 

 granules of fat. It is constituted of glan- 

 dular masses, irregular in magnitude and 

 form, and loosely connected one with 

 another, each of which masses is composed 

 of a number of lobules, closely compacted 

 and united together. These insulated lob- 

 ulous portions receive small arteries, from 

 which the milk is secreted. The former, 

 by repeatedly conjoining one with another, 

 become at length several demonstrable 

 canals, radiating from every part, and dilat- 

 ing to hold the milk. 



When the udder becomes charged with 

 milk, it flows into the teat and distends it. 

 Suction is apparently an operation purely 

 mechanical. The teat is seized and closely 

 compressed by the lips of the foal ; and the 

 imbibing effort which foUows has a ten- 

 dency to produce a vacuum, or raise the 

 valve at the upper part of the teat, and the 

 milk passes from the reservoirs into the 

 mouth. 



