VOL. XL, NO. 480 



BECEHBEK, 1906 



THE 



AMERICAN 

 NATURALIST 



A MONTHLY JOUKNAI 

 DEVOTED TO THE NATURAL SCIENCES 

 IN THEIR WIDEST SENSE 



CONTENTS 



II. The Alpine Flora of Colorado .... PROFESSOE T. D. A. COCKEBELL 861 



III. Blood Gills of Simulium pictipes DB. T. J. HEADLEE 876 



IV. Publications Eeceivsd 887 



BOSTON, U. S. A. 

 GINN & COMPANY, PUBLISHERS 

 29 BEACON STREET 



HeWYork Chicago London, W 0. 



T8 Fmh Avenue 878-388 waUaih Avenue »«. Martin's Street 



