The American 



MONTHLY 



SCOP 



CONTAINING 



CONTRIBUTIONS TO BIOLOGY. 



Chas. W. Smiley, Publisher, Washington, D. C. 

 TERMS: For the United States, $2.00. For Great Britain, 8 Shillings. 



'OL. XV, No. 3. 



MARCH, 1894. 



No. 171. 



