WALKER PRIZES IN NATURAL HISTORY. 
By the provisions of the will of the late Dr. William Johnson Walker two 
prizes are annually offered by the Boston Society of Natural History for the 
best memoirs written in the English language on subjects proposed by a 
Committee appointed by the Council. 
For the best memoir presented a prize of sixty dollars may be awarded ; 
if, however, the memoir be one of marked merit, the amount may be 
increased to one hundred dollars, at the discretion of the Committee. 
For the next best memoir, a prize not exceeding fifty dollars may be 
awarded. 
Prizes will not be awarded unless the memoirs presented are of adequate 
merit. 
The competition for these prizes ts not restricted, but zs open to all. 
Attention is especially called to the following points : — 
1. In all cases the memoirs are to be based on a considerable body of 
original and unpublished work, accompanied by a general review of the 
literature of the subject. 
2. Anything in the memoir which shall furnish proof of the identity of 
the author shall be considered as debarring the essay from competition. 
3. Preference will be given to memoirs showing intrinsic evidence of 
being based upon researches made directly in competition for the prize. 
4. Each memoir must be accompanied by a sealed envelope enclosing 
the author’s name and superscribed with a motto corresponding to one 
borne by the manuscript, and must be in the hands of the Secretary on or 
before April 1 of the year for which the aa is offered. 
SUBJECTS FOR 1899 : — 
I. Is there fundamental difference between “equation division ” and 
“reduction division ” in the division of cells? 
2. The phenomena and laws of hybridization. 
eee FOR 1900: ee 
Stratigraphy and correlation of the ian formations of f any part — 
of hice England. o 
2. A study in pon stratigraphy and correlation. 
SAMUEL HENSHAW, 7 
Secretary. : 
Boston Society of Natural History, 
Boston, Mass., U. S. A. 
