102 



SCIENCE 



[N. S. Vol. XLIX. No. 1257 



has been a matter of very irregular growth, 

 now one phase, now another forging ahead; 

 the mistakes of one generation being corrected 

 by a later one and the faulty interpretations 

 of limited knowledge clarified with wider basis 

 of fact. Often the progress of one branch 

 has been definitely halted till the developments 

 in other fields have given the data necessary 

 for a clear comprehension and satisfactory 

 solution of its problems. 



The rapid advance of one phase may have 

 resulted from individual taste or interest or 

 again from some insistent demand frora an 

 associated or dependent field. Comparative 

 anatomy has been pushed forward by the 

 needs of human anatomy; in fact many 

 .phases of zoology particularly related to medi- 

 cine have had their progress determined by 

 the needs of this applied science. The med- 

 ical importance of certain mosquitoes and flies 

 has stimulated tremendously the interest in 

 these groups and the amount of study devoted 

 to them. 



Extremely destructive insects, from a human 

 standpoint, have been investigated with far 

 greater assiduity than is true of most of the 

 species devoid of economic interest. Attract- 

 ive habits or a human interest perhaps ac- 

 counts for the fact that birds have been 

 much more studied and are far better known 

 than the worms on which they feed, and that 

 ants, bees and wasps with social habits have 

 claimed attention to the neglect of less highly 

 specialized forms. 



Primitive observations of the character and 

 habits of animals, stimulated no doubt by the 

 needs for food and the domestication of avail- 

 able forms, has grown into definite knowledge 

 concerning the habits and life histories and 

 other general matter. The study of animal 

 activities must have been closely coincident 

 with that of the animal mechanism and these 

 gradually differentiated into the now almost 

 too widely separated branches of morphology 

 and physiology, while passing further into the 

 realm of the interactions with sui'rounding 

 forces or interrelations with other organisms 

 has developed into the ecology of modern 

 times. Eecognition of the succession of gen- 



erations of like animals laid the foundations 

 for a knowledge of the main facts of heredity 

 and these with later knowledge of the mechan- 

 ism of inlieritance gives us our modem con- 

 ceptions of genetics. 



Attempts to designate the various animals 

 must have developed by slow d^rees into the 

 primitive recognition of species and quite nat- 

 urally into the further association of groups 

 of similar kinds such as birds, fishes, reptiles, 

 etc., which were imdoubtedly the beginnings 

 of our systems of classification ; systems whose 

 complexities now sometimes become the de- 

 spair of the initiated as well as of the amateur. 



Comparison of the animals of different geo- 

 graphical regions involving the recognition of 

 distribution, of adaptations to climate, topog- 

 raphy and other natural features and to re- 

 striction of modes of life must have early 

 entered into the realm of zoology. Curiosity 

 as to the meaning of fossils grew with our 

 sister science of geology into modern paleon- 

 tology with all its sign, leant contributions to 

 the interpretation of life and its historic 

 development. 



Speculation as to the origin of animal life 

 certainly came at an early date and the long 

 tangle of conceptions of the processes of 

 evolution which have culminated in our doc- 

 trine of descent was started on its devious 

 path. 



But it is not my purpose to trace in detail 

 the gTOwth of the different branches of zoolog- 

 ical science. What I would like to emphasize 

 just now is that we have a large number of 

 quite distinct phases of our study and that 

 these have become so specialized that the 

 ■workers in one branch may have y^.-jt little 

 conception of the nature of the problems, the 

 technique or the difficulties attending the ad- 

 vancement of knowledge in another branch. 



In some cases this seems to have resulted 

 in lack of sympathy or in misunderstandings 

 that have served as a handicap to the progress 

 of the science as a whole and a mutual recog- 

 nition of the interdependence of all branches 

 should be helpful in determining future prog- 

 ress. The truth is that there is no branch of 

 zoology overworked or exhausted and there is 



