ANIMAL, parts of, substances which compose the bodies of animals !nay be arranged under the following heads: 1. Bones and Shells 2. Horns and Nails 3, Muscles 4. Skin 5. Membranes 6. Tendons and ligaments 7. Glands 8. Brain and nerves 9. Hair and feathers 10. Silk and similar bodies.
Besides these substances, which con stitute the solid part of the bodies of ani mals, there are a number of fluids, the most important of which is the blood, which pervades every part of the system in all the larger animals : the rest are known by the name of secretions, because they are formed, or secreted, as the ana tomists term it, from the blood. The principal animal secretions arc the fol lowing: 1. Milk 2. Egys 3. Saliva 4. Pancreatic juice 5. Bile 6. Ccrumen 7. Tears 8. Liquor of the pericardium 9. humours of the eye 10. Mucus of the nose, &c.
11. Sinovia 12. Semen 13. Liquor of the amnios 14. Poisonous secretions.
Various substances are separated either from the blood or the food, on purpose to be afterwards thrown out of the body as useless or hurtful. These are called ex
cretions. The most important of them are, 1. Urine 2. Fxces.
Besides the liquids which are secreted for the different purposes of healthy ani mals, there are others which make their app arance only during disease, and whith may therefore be called morbid se cretions. The most important of these are the following : 1. Pus 2. The liquor of dropsy 3. The liquor of blisters.
To these we must add several solid bo: dies, which are occasionally formed in different cavities, in consequence of the diseased action of the parts. They may be called morbid concretions. ThC most remarkable of them are the following: 1. Salivary calculi 2. Concretions in the lungs, liver, brain, &c.
3. Intestinal calculi 4. Biliary calculi 5. Urinary calculi 6. Gouty calculi.