Copyright, igo7, by W. B. Saunders Company. Revised, reprinted, and recopyrighted July, 

 1913. Reprinted January, IQ16, October, 1917, May, 1918, and September, 1919. Re- 

 vised, reprinted, and recopyrighted September, 1920. Reprinted June, 1924, and 

 May, 1927. Revised, reprinted, and recopyrighted, June, 1928 



Copyright, 1928, by W. B. Saunders Company 



MADE IN U. 



PRESS OF 



W B. SAUNOERS COMPANV 



f>HIL.AOEI.PHI A 



