780 



SCIENCE. 



[N. S. Vol. III. No. 73. 



extends three-fourths of an incli caudad from 

 the end of the sternum. In outward aspect 

 this tract is identical with the others. On rais- 

 ing the skin the glandular structure is very evi- 

 dent ; it is the same in appearance, under the 

 lens, as that of the lateral tracts, but thicker as 

 well as more extensive. 



All three tracts are strictly subcutaneous, and 

 come away from the subjacent parts when the 

 skin is raised. They are supplied by large cu- 

 taneous vessels, the ramifications of which are 

 conspicuous beneath the integument. This vas- 

 cularity reddens the minutely granular texture 

 of the glands, which a low magnifying power 

 discloses. The three areas appear alike in both 

 sexes. Elliott Coues. 



Washington, D. C, May 7, 1896. 



INSTINCT. 



Editor Science : It seems to me that it 

 would be well to keep the issue with which this 

 discussion started in view, and then the di- 

 rection in which the truth lies will be clearer. 

 Nothing could be more explicit that the state- 

 ment by ' The "Writer of the Note ' in Science of 

 February 14th, which was this : "A chick will 

 peck instinctively, but must be taught to drink. 

 Chicks have learned to drink for countless gen- 

 erations, but the acquired action has not become 

 instinctive. ' ' 



In other words, the view that eating is in- 

 stinctive and drinking is not, was that taught 

 by Prof Morgan and endorsed by ' The Writer 

 of the Note ' in a subsequent communication. 

 Feeling that an important truth was being 

 imperilled, I advanced facts to show that such 

 a view was untenable. This was followed by 

 the recital of additional facts by others, so that 

 it was plain to myself — more so than ever — that 

 such a theory as that first advanced was not 

 sound. I was aware that all three of the writers 

 supporting this view were in accord, constitu- 

 ting a sort of trinity in unity ; there was, never- 

 theless, a great lack of harmony which seemed 

 to be owing to the somewhat important defect 

 that their views were not endorsed by Nature. 



Now, to my surprise. Prof Baldwin claims 

 that I have missed the real point which he 

 takes to be that an instinct may be only ' half 

 congenital,' and cites this drinking of chicks; 



but according to the above quotation drinking 

 is not instinctive at all, so that it looks as if the 

 shoe was on the other foot. 



In 1894, in a paper read before the Roy. Soc. 

 Can. on ' The Psychic Development of Young 

 Animals,' published in the Pi'oceedings of the 

 Society for 1895 and a copy of which was for- 

 warded to Prof. Baldwin, I emphasized the 

 conception that instinctive acts are never perfect . 

 at first, or, as Prof Baldwin would prefer to say, 

 are only partially congenital, though whether 

 such an expression as ' half congenital ' is a 

 valuable addition to the English language, I 

 doubt. Now it would be strange that I should 

 alter my own views without noting the change, 

 and miss the point in a matter which I was, I 

 think, the first to emphasize ; in fact, I have in 

 this very correspondence in Science urged this 

 view— the imperfection of instincts. If Prof. 

 Baldwin and those he professes to interpret will 

 grant that eating and drinking in chicks are in- 

 stinctive ; that both alike are imperfect at birth ; 

 that congenitally the chick is in the same con- 

 dition to all intents and purposes as regards 

 eating and drinking, he will, I believe, be in 

 accord with the facts, and we shall all agree that 

 the much overlooked imperfection of instincts 

 is well illustrated by the subjects under dis- 

 cussion, but I should like to add, universal in 

 its application, though in varying degree, the 

 imperfection being in some cases not very ob- 

 vious to our inadequate observation. 



But in discussing evolution I feel that we 

 are on a different plane. Here the appeal to 

 facts is of a much less decisive character. 



I have been trying since reading Prof. Bald- 

 win's letter in Science of May 1st, in reply 

 to my own, to ascertain his real views in regard 

 to evolution, and have some hesitation in de- 

 ciding whether I really grasp his meaning or 

 not. However a few concrete cases may make 

 matters plainer. A and B are, let us suppose, 

 two individuals that survive because they can 

 and do adapt to the environment ; X and Y die 

 because they cannot; or in Prof. Baldwin's 

 terminology, A and B adapt to their ' Social 

 Heredity' constituting ' organic selection ' which 

 is ontogenetic or affects the individual. But 

 the survival of individuals specially adapted af- 

 fects the race or phylum. But surely an indi- 



