92 CHAS. W. HARC.I 1 1 . 



there is not that degree of constancy, or character of reaction, 

 in orientation which would warrant a tropic interpretation of 

 any sort. 



lint <m the other hand let it not he inferred that behavior is 

 chaotic or beyond scientific explanation. As I have elsewhere 

 pointed out, reactions and adjustments in relation to food-getting, 

 respiration, etc., are among the most fundamental of all phases of 

 behavior. These creatures must live, hence must have food ; but 

 they are sessile, and therefore must utilize such as may come 

 within reach. Furthermore, they must respire, and hence must 

 have room within which to expand the gills. All this implies 

 that such colonial species must of necessity frequently resort to 

 movements of readjustment directed to the above imperative 

 ends. In most of these creatures it so happens that one and the 

 same organ is involved in this dual function of food-taking and 

 respiration; a fact of some significance in simplifying or com- 

 plicating, according to condition, certain phases of behavior. 

 To the writer it seems probable to the point of certainty that 

 the aspects of behavior which have been under review are chiefly 

 but varied expressions of these common functions. In other 

 words, they are aspects of adjustment in the complex struggle 

 for existence varying modes in which each species has worked. 

 out its own special problem of life. 



In the light of this mode of interpretation the complicated 

 serpentine torsions of the tubes of Hydroides and Pomatoccras 

 arc the most natural expressions of just such "trial movements" 

 as one might expect. Likewise the bending aspects of the 

 flexible tubes of Pot am ilia and Spirographis are not mysterious 

 enigmas over which students of behavior need array themselves 

 in warring camps, but rather the simple expressions of those 

 individual adjustments called for in the varying struggle of 

 life, to the interpretation of which Huxley would have found 

 necessary only "trained and organized common sense" 



I am quite aware that to speak of individuality, or autonomy, 

 or spontaneity as factors involved in problems of animal behavior 

 may to some exponents of mechanism seem "no explanation," 

 and of significance only to the psychologist. But as I ha\e 

 earlier pointed out, they are facts, and they bulk large in tin- sum 



