CONNECTIVE TISSUE. 15 



which run through it. As connective tissue has only the 

 passive action of support, I need hardly say, that the coarser 

 in grain a muscle is, the less powerful will it be ; although it 

 will be better able to resist the effects of external violence 

 than one of finer grain. The protective duty of connective 

 tissue, as regards muscles, may be readily inferred from the 

 fact that the less exposed muscles are to injury from with- 

 out, by reason of their position, the less connective tissue do 

 they contain. This tissue, also, forms ligaments and ten- 

 dons, and ensheathes bones, cartilages, nerves, etc. There is 

 always a large amount of it immediately underneath the skin, 

 in the form of loose fibrous sheets, as we may see in the dead 

 animal. The presence of a great quantity of it in this 

 position will, naturally, cause the underlying parts to be ill- 

 defined, a fact which will be especially noticeable about the 

 tendons and ligaments below the knees and hocks, owing to the 

 absence of muscle about these parts. We may, therefore, draw 

 the following deductions : (i) That, as the thickness of the 

 skin is a measure of the amount of connective tissue it con- 

 tains ; the thicker the hide, other things being equal, the more 

 connective tissue will there be in and about the muscles. 

 (2) That, as its action is only passive, the more of it a 

 muscle contains, the slower will be the movements of the 

 muscle. Hence, we may reasonably conclude that the fact 

 of a horse having a thick skin, and ill-defined suspensory 

 ligaments, owing to natural " fleshiness," would warrant us 

 in supposing that he was deficient in speed. I may remark 

 that, with age, the amount of connective tissue in the body 

 greatly increases. As M. Guerin states : "In the old man, 

 the tendon seems to invade the muscle, so that the portion of 

 the calf of the leg which remains, is placed very high, and 



