260 MINUTE MARVELS OF NATURE 



The hairs of the mouse and other rodents 

 exhibit beautiful and interesting examples of hair 

 structure on account of the arrangement of their 

 air-cells. The mouse hair, Fig. 180, shows an 



Fig. 180. Mouse hair 



arrangement in the larger hairs of three longitu- 

 dinal series of cells, while the finer hairs have but 

 one or two rows of cells. 



Human hairs do not present such pretty exam- 

 ples as some of those of the lower animals. A 

 few shavings from the human beard are shown at 

 Fig. 1 8 1. These it will be observed present a 

 dark appearance along their centres, and this is 



