7° 



THE CONDOR Vot. IX 



Another group of (luestious which ornithologists are in an especially favorable 

 position to tackle is that of correlated characters and variations. Much could be 

 done here without resort to breeding experiments. Observation coupled with 

 anatom}^ and embryolog.y could go a long way. Perhaps the most practical and in- 

 teresting single question is that of whether or not the superficial characters ordina- 

 rily used for differentiating species are not associated, even if not actually cor- 

 related with other more deeply seated structural characters. I am not thinking 

 about anatomical features that might serve as reliable tests of affinity, and hence as 

 bases of more natural classifications. Of course I do not neglect the labors of such 

 anatomists as Huxley, Fuerbringer, Shufeldt, I^ucas and others in this field. Tax- 

 onomic trials with anatomical data have been carried far enough to justify, proba- 

 bly, the opinion of Newton and Gadow that "it is hopeless to attempt to arrive at 

 a natural classification of Birds by a mechanical arrangement of even a great num- 

 ber of alleged leading characters." 



What I have in mind is quite a different matter. It is this: Given two or 

 more species of a genus well defined by characters generally used in ornithology, 

 what other differentiating characters, if any, would a thorogoing examination of 

 the whole animal discover ? 



I am quite sure that we must sooner or later, see that characterizing a species 

 just far enough to place it in an artificial system of classification, is a very differ- 

 ent matter from defining it thru and thru: that is, in such a way that nothing 

 whatever truly distinctive about it shall have been left out. This is the sort of 

 definition we shall demand when once we get red-hot after the problem of what a 

 species really is. An individual bird consists of all there is of it from the time in- 

 cubation begins until it dies. Isn't that so? If not, what segment of the life 

 cycle does not belong to the individual? I am sure no bird man, thoroly imbued 

 with what I take to be the distinctive spirit of ornithology, has the least desire to 

 thus fragment a bird's life. 



Well, if the real bird is the whole life of the bird, then for its whole life it is a 

 member of its particular species; and if at any period of its life it has characters 

 that are different from those possessed by any other species whatever, these must 

 be specific characters and would surely be noted in a full description of the species. 

 This, of course, means practically that the &gg, not merely the e^-£--s/ie//, the sperm, 

 the embryo at all its stages, the fledgling, the adult bird in all its phases of 

 moulting, with all its habits and songs, would have to be attended to in a thoro- 

 going definition of the species. 



Ornithologists have as a whole done better in this regard than other zoologists, 

 and that is just the reason why they should do still more — vastly more — in the 

 same direction. "To him that hath shall be given." The complement of the old 

 truth is more to the point here: "Of him that hath accomplished shall more be 

 expected." 



One might easily designate other places wherein ornithology may be expected to 

 shine in the new era of exacter, broader observation, and more critical testing of 

 hypotheses and definitions into which biology is now fairly entered. The hard 

 task, for instance, of establishing a more exact and trustworthy scale of values for 

 characters, ornithology should contribute to largely. What department of biology 

 except possibly entomology, is in better position to handle color from this point of 

 view? It would be easy to designate other places in evolutionary theory at which 

 ornithology might work with peculiar efficacy; but these are enough for a liberal 

 program . 



