THE AMERICAN 



MONTHLY 



Microscopical Journal 



ft/L I CONTAINING 



CONTRIBUTIONS TO BIOLOGYJ 



Volume XTII 



FOR 



1893 



FOUNDED IN 1880, BY ROMYN HITCHCOCK, F. R M. S. 



PUBLISHED. SINCE 1887, BY CHAS. W. SMILEY. 



WASHINGTON. D. C. 



