1042 The American Naturalist. [November, 
Marshall McDonald.—To his many friends, to the public hav- 
ing an interest in the fisheries which he labored so successfully to en- 
rich, and to the biologists whose scientific labors he appreciated and 
utilized, the death of Colonel Marshall McDonald, the late U.S. Fish 
Commissioner, is a severe loss. 
Though the work in which he was directly engaged in his official 
capacity was of an eminently practical nature, he early recognized that 
science was the ally of practice, or rather that the best practice is 
science, and sought in the working biologist his most helpful colaborer 
whom he always urged to turn to the solution of the problems which 
he had ever before him. 
With Col. McDonald pisciculture in this country was fast advancing 
to the secure foundations of scientific method now enjoyed to a consid- 
erable degree by its sister art, agriculture. His method was not to 
experiment at hap-hazard in the hope of making a lucky hit that 
might solve the problem at hand, but by the most painstaking investi- 
gation to study the fisheries in their widest relations, to build up a firm 
basis of facts scientifically acquired, and from these to draw conclu- 
sions which were as practical as they were far-reaching and accurate. 
This method was necessarily as slow as its results are enduring, and we 
have yet to see the full fruition of his labors. As a consequence the 
work has met with the usual criticism from impatient persons of cir- 
cumscribed view, who would measure the value of the Fish Commis- 
sion’s labors only by the number of young fry annually raised, or 
supposed to have been raised, failing to recognize the practical fact, 
which alone will appeal in such cases, that many of the methods and 
apparatus now generally employed in local hatcheries have resulted 
from the careful scientific inquiry conducted under Col. McDonald’s 
direction, and without which the highly gratifying and useful results 
attained would not now be possible. 
One of the last important works of Col. McDonald’s life was to plan 
a biological and physical survey of far greater thoroughness than any 
previously undertaken. He was convinced that the first step toward 
a comprehensive knowledge of the conditions of greatest productiveness 
of the fisheries is an understanding of the primary food supply—the 
“aquatic pasturage,” he called it. This he hoped to gain by an 
accurate qualitative and quantitative analysis of the unicellular plank- 
ton and littoral life, which, in turn, involves the chemico-biological and 
physico-biological questions concerning the ultimate relation existing 
between land waste and sea utilization, and incidentally a study of the 
life-histories and interrelations of myriads of animals and plants. 
