UNIVERSITY OF COLORADO BULLETIN 



Vol. XV, No. 6 



Publiihed MomHy fy lit Rtgtnis of iht Univeraiy of Colorado. 

 Enterid at lie Poll Ofice, Boulder, Colorado, as ucond-class mail mailer. 



THE 



UNIVERSITY OF COLORADO 



STUDIES 



Boulder, Colorado, June, 1915 



OlNZitAL Si>iu, No. 83 



Studih Simes, Vol. XI, No. 4 



