OBJECTS.] INTRODUCTORY. 91 



In this respect, the fowl is like all other animals ; it 

 cannot manufacture the proteid materials of its body, 

 but it has to take them ready made, or in a con- 

 dition which requires but very slight modification, by 

 devouring the bodies either of other animals or of 

 plants. The animal or vegetable substances devoured 

 are taken into the animal's stomach; they are there 

 digested or dissolved ; and thus they are fitted to be 

 distributed to all parts of the fowl's own body, and 

 applied to its maintenance and growth. 



64. The Living Animal, after it has grown 

 up, detaches part of its Substance, which has 

 the Power of growing into a similar Animal, 

 as an Egg. 



The fowl's egg is formed in the body of the hen, 

 and is, in fact, part of her body inclosed in a shell 

 and detached. It contains a minute rudiment of a 

 fowl ; and when it is kept at a proper temperature 

 by the hen's sitting upon it, or otherwise, for three 

 weeks, this rudiment grows, or develops, at the 

 expense of the materials contained in the yolk and 

 the white, into a small bird, the chick, which is then 

 hatched and grows into a fowl. The animal, there- 

 fore, is produced by the development of a germ in 

 the same way as the plant ; and, in this respect, all 

 plants and all animals agree with one another and 

 differ from all mineral matter. 



65. Living Bodies differ from Mineral 

 Bodies in their Essential Composition, in 

 the manner of their Growth, and in the fact 

 that they are reproduced by Germs. 



Thus there is a verv broad distinction between 



