Gia Us BONS Bi Dal Ee bein 23 

Relatively little time has been left for problems in ornithology, but 
Doctor Forbes in 1905 undertook a new kind of investigation of the 
birds of Illinois which has produced interesting results. An under- 
standing of the general purpose of this investigation and of the method 
of operation is made clear in the following quotations from two of the 
five papers already published in which the data are’ presented and dis- 
cussed. These quotations will also serve to give something of an idea 
of the clearsminded, comprehensive point of view with which Doctor 
Forbes has attacked such problems and of his unusual skill in giving 
expression to his thoughts. The general purpose of the studies is given 
in the following excerpt from a paper entitled, ‘““An Ornithological 
Cross-Section of Illinois in Autumn,” published in 1907 in the Bulletin 
of the Illinois State Laboratory of Natural History (Vol. VII): 
. “In special ecology the species is the all-important, dominat- 
ing center; in general ecology each species takes its appropriate place 
—dominant, important, subordinate, or insignificant—according to its 
dynamic value as a part of the whole.”’ | 
‘Precise studies in animal ecology have heretofore been made mainly 
in the special field, necessarily so in the beginning since a knowledge of 
the ecology of species must precede that of groups or assemblages of 
species. These special studies are, however, merely preliminary to a 
general study of the dynamic system of organic life as exhibited in its 
larger and more complex units. Without the corrective and organizing 
influence of such a study of the system as a whole, our ideas of that 
system must be badly proportioned and correspondingly inadequate or 
misleading—a fact readily illustrated by the state of our knowledge 
and opinion respecting the ecological significance of birds. 
“To learn what we now know of the effects of the activities of birds 
has required much difficult, expert, time-consuming study, especially 
of the details of their food, since it is mainly through the food relation 
that birds affect the welfare of other animals and of plants. These 
studies, although both qualitative and quantitative as related to the 
welfare of the various species of birds themselves, have been qualitative 
only as concerning the relation of birds to the general welfare; and we 
have little but vague estimate and doubtful surmise in place of a definite 
knowledge of the relative ecological value of the various species, and 
equally little knowledge, in consequence, of the total significance of 
birds as a class. We do know fairly well (owing, in part, to the early 
work of this Laboratory!, but mainly to that of the United States 
Biological Survey) the principal features of the food of many species 
of our common birds, but we cannot lay these data together for an 
intelligent estimate of the total effect of the life of birds on their environ- 
ment except on the supposition that the various species are about 
equally abundant wherever they occur. That this is not the fact is 
1See Bull. Ill. State Lab. Nat. Hist., Nos. 3 and 6, Vol. I. 
