ORIGINAL COMMUNICATIONS. 



Variation-Statistics in Zoology. 1 



By Dr. Georg Duncker. 



Zoological and botanical objects have usually been regarded as isolated 

 products of nature, to be described carefully and to be grouped, accord- 

 ing to the degree of their morphological and ontogenetic likeness, 

 under abstract conceptions, the systematic categories. Yet this 

 customary manner of considering biological objects is insufficient, 

 since individuals of any systematic category never occur isolated, but 

 always in larger or smaller complexes or groups of individuals. For 

 about ten years another point of view has been finding increased favour ; 

 it has been recognised that not only the morphological characters of 

 single individuals, but especially those of the natural complexes of homo- 

 geneous individuals, are worthy objects of investigation. This kind of 

 investigation takes the same place in zoology and botany as ethno- 

 graphy does in anthropology. In reference to its special aims, it has 

 worked out its own methods, which in its various stages of development 

 and different branches, may be summed up under the title Statistics of 

 Variation. Let us briefly consider this method and its results. 



In anthropology statistics of variation have been already utilised 

 for forty or fifty years. This is partly due to the early scientific 

 interest in the individual differences of the characters of man, and 

 partly to the fact that the problems of this branch of biology cannot 

 be solved by isolated observations made on single individuals, but 

 require intensive investigations of the actual groups of individuals. 

 This is evidently the case with racial problems in anthropology. 



Primarily, zoology and botany are occupied in investigating the 

 characters and development of individuals (anatomical morphology 

 and embryology). We also find that the individuals, morphologically 

 dissimilar, are classifiable, according to their degree of likeness, into 

 higher or lower categories, which are regarded as elementary objects 

 of scientific investigation (systematic zoology, comparative anatomy). 



1 Lecture delivered at the meeting of the Deutsche Zoologische Gesellschaft at 

 Hamburg, May 1899. 



22 — nat. sc. — vol. xv. no. 93. 325 



