154 TRANSFORMATION OF ANIMALS. 



many subjects, this digestive power extends much farther than 

 through the stomach. I have often found, that, after it had 

 dissolved the stomach at the usual place, the contents of the 

 stomach had come into contact with the spleen and diaphragm, 

 had partly dissolved the adjacent side of the spleen, and had 

 dissolved the stomach quite through ; so that the contents of 

 the stomach were found in the cavity of the thorax, and had 

 even affected the lungs in a small degree.' 



CHAPTER VII. 



OF THE TRANSFORMATION OF ANIMALS. 



THE transformation of caterpillars, and of different kinds of 

 worms, into winged insects, has long excited the attention 

 as well as the admiration of mankind. But the truth is. 

 that every animal, without exception, undergoes changes 

 in structure, mode of existence, and external appearances. 

 Mankind, from their embryo state, to their final dissolution, 

 assume many different forms. At birth, the form, the sym- 

 metry, and organs of the animal are by no means complete. 

 The head continues for some time to be disproportion ally 

 large ; the hands and feet are not properly shaped ; the legs 

 are crooked ; and the hair on the head is short and scanty ; no 

 teeth as yet appear : and there is not a vestige of a beard. 

 In a few months, however, the symmetry of all the parts is 

 evidently improved, and the teeth begin to shoot. The 

 growth of the whole body, as well as the strength and beauty 

 of its form, gradually advances to perfection till the sixth or 

 seventh year, when another change takes place. At this 

 period, the first set of teeth are shed, and are replaced by 

 new ones. From boyhood to youth, the size of the body, and 

 of its different members, increases. During youth, several 

 important changes are produced in the system. The beard 

 now makes its appearance ; and the dimensions of the body, 

 in most individuals, are suddenly augmented. From this 

 period to the age of twenty-five or thirty, the muscles swell, 

 their interstices are filled with fat, the parts bear a proper 

 proportion to each other, and man may now be considered as 

 a perfect animal. In this state of bodily perfection and vigor, 



