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SCIENCE 



[Vol. LVI, No. 1456 



ing to the normal eiirve of enx>r, as most cliance 

 determined phenomena are, ibut instead obey 

 with estraordinary exactness, as has been 

 shown by Willis and Yide,* the rule that the 

 logarithms of the frequency of genera plotted 

 to the logarithms of the size of the same genera 

 (i. e., the number of species in each), give a 

 straight line. 



It is with much satisfaction that we find the 

 leading exponent of the reigning mode in 

 present-day biology, Bateson,* saying of tax- 

 onomy : 



I had expected that genetics would provide at 

 once common ground for the systematist and the 

 laboratory worker. This hope has been disap- 

 pointed. Each still keeps apart. Systematic 

 literature grows precisely as if the genetical dis- 

 coveries had never been made and the geneticists 

 more and more withdraw each into his special 

 "claim"- — a most lamentable result. Both are 

 to blajue. If we can not persuade the systemat- 

 ists to come to us, at least we can go to them. 

 They too have built up a vast edifice of knowl- 

 edge which they are willing to share with us, and 

 which we greatly need. They too have never lost 

 that longing for the truth about evolution which 

 to men of my date is the salt of biology, and the 

 impulse which made us biologists. It is from 

 them that the raw materials for our researches 

 are to be drawn, which alone can give catholicity 

 and breadth to our studies. We and the sys- 

 temalti^ts have to devise a common language. 



The separation between the laboratory men 

 and the systematists already imperils the work. 

 I might almost say the sanity, of both. The sys- 

 tematists will feel ithe ground fall from beneath 

 their feet, when they learn and realize what 

 genetics has accomplished, and we close students 

 of specially chosen examples may find our eyes 

 dazzled and blinded when we look up from our 

 work-tables to contemplate the brilliant vision of 

 the natural world in its boundless complexity. 



It seems probable that we shall before long 

 witness a return to a saner attitude than has 

 prevailed in the last quarter of a century in 



3-WilUs, J. C, and Yule, G. U.: "Some Sta- 

 tistics of Evolution and Geographical Distribu- 

 tion in Plants and Animals, and Their Signifi- 

 cance," Nature, February 9, 1922, pp. 177-179. 



4 Bateson, W. : ' ' Evolutionary Faith and Mod- 

 ern Doubts," Science, N. S., VoL 55, pp. 55-61, 

 1922. 



regard to systematic zoology and botany; and 

 in the training of oui- students, by not be- 

 ginning specialization too soon and .too vio- 

 lently, give them a more adequate conception 

 than they now get of the orderliness and the 

 diversity which together characterize animate 

 nature as a whole. 



Ill 



The dominant mode in biology in my student 

 days was morphology. I was nurtured on the 

 somewhat arid problems of vertebrate cephalo- 

 genesis and tihe components of the cranial 

 nerves. Probably few students in these days 

 are excited iby such problemis. A vague aware- 

 ness that there are such things as cranial 

 nerves no doubt suffices and everyone is just 

 as happy. The whole subject of pure mor- 

 phology, as it was cultivated twenty-five years 

 ago, seems singularly sterile now. It was a 

 highly developed discipline, with a set of rules 

 as rigid, and also be it said about as soul- 

 stirring, as those of the Greek grammar. In 

 its fine spun theories about homology, meta- 

 merism and the like, biology got off on a wrong 

 track, which, as is now practically universally 

 admitted, had only a blind ending. 



But this does not mean, as those of the 

 younger generation are apt rashly to conclude, 

 that the old morphology was of no value. 

 Intrinsically it was of great value. Pew things 

 will transcend in importance in the study of 

 biology, the finding out of ali that can be 

 learned about the way in which living machines 

 are put together. As long as this purely 

 descriptive purpose was the primary and essen- 

 tial object of morphological study, all was 

 well. The business only began to go bankrupt 

 when it took on an essentially metaphysical 

 purpose, ajnd a logically bad, not to say hope- 

 less one, at that. For what the pure morpholo- 

 gists of the eighties and early nineties were 

 trying to do was to infer from purely static 

 phenomena (the intimate structure of the 

 body) the dynamic relations in a coxu'se of 

 events (organic evolution). Such a task 

 would have been perceived to be hopeless long 

 before it was, except for the seductive lure of 

 certain rules by which the game was played, 

 which rules (such as ontogenetic recapitulation 



