636 



SCIENCE. 



[N. S. Vol. V. No. 121. 



sidered as directing the course of evolution 

 through organic selection. 



8. Tradition (Lloyd Morgan): the hand- 

 ing on from generation to generation (in- 

 dependently of physical heredity) of ac- 

 quired habits. 



9. Social Heredity (Baldwin): the process 

 by which the individuals of each generation 

 acquire the matter of tradition and grow 

 into the habits and usages of their kind.* 



J. Mark Baldwin. 

 Peincbton University, 



March 13, 1897. 



WHAT IS A TYPE IN NATURAL HISTORY f 



All naturalists concede that type speci- 

 mens constitute the most important ma- 

 terial in a museum of natural history. The 

 true appreciation of this fact, however, is 

 of recent date, and is shown in the numer- 

 ous lately published catalogues of types pos- 

 sessed by different museums. The greater 

 number of these publications have appeared 

 in England and America. This just valua- 

 tion of type material in recent years has 

 come about through the work of specialists 

 in their efforts to monograph groups of 

 organisms. In those branches of natural his- 

 tory where original descriptions are usually 

 accompanied by figures, the value of type 

 material is not so apparent as where no 

 figures are given, but in all branches of this 

 science except bacteriology, it is upon the 

 type material that the entities of natural 



* Professor Lloyd Morgan thinks this term unneces- 

 sary. It has the advantage, however, of falling in 

 with the popular use of the phrases ' social heritage ' 

 and ' social inheritance.' On the other hand, ' tradi- 

 tion ' seems quite inadequate; as generally used it 

 signifies that which is handed on, the material ; while 

 In the case of animals we have to deal mainly with 

 the process of acquisition. ' Social heredity ' also 

 calls attention to the linking of one generation to an- 

 other. However, I think there is room for both 

 terms. For further justification of the terms ' Social 

 Heredity' and 'Organic Selection,' I may refer to 

 the American Naturalist, July, 1896, pp. 552 £E. 



history and its taxonomy rest. It is there- 

 fore of the greatest importance to learn the 

 whereabouts of types. The object of this 

 article, however, is not to point out the 

 great scientific value of type specimens, but 

 to determine what constitutes a type and 

 what kinds of types exist. 



There is considerable diversity of opinion 

 as to what is meant by a type. One writer 

 states that " By a type is meant the original 

 specimen to which any generic or specific 

 name was first assigned."* 



The late Dr. G. Brown Goode writes 

 that 



By a type is meant a specimen which has been used 

 by the author of a systematic paper as the basis of 

 detailed study, and as the foundation of a specific 

 name. In cases where a considerable number of 

 specimens has been used, it is desirable to separate 

 one or more as being the primary types, while the 

 other specimens, which may have been used in the 

 same study for the purpose of comparison, may be 

 regarded as collateral types.-f 



A mammalogist further states that " The 

 word ' type ' itself, when first intro- 

 duced, was meant to refer to the particular 

 specimen (in the singular) originally de- 

 scribed, but it was soon naturally applied 

 to any individual of the original series, if 

 more than one specimen was examined by 

 the describer."! 



These citations clearly show that a type 

 is not always restricted to a single speci- 

 men selected by an author, but also applies 

 to several, or even to all the specimens con- 

 tained in the original lot. Moreover, the 

 word type has been applied to specimens 

 sent out by the author of a species, but not 



*T. McKenny Hughes, Catalogue of the Type Fos- 

 sils in the Woodwardian Museum, Cambridge, 1891 ; 

 prepared by Henry Woods. 



fCircular letter of July 1st, 1893, to Curators in 

 the U. S. National Museum. 



t Suggestions for the more definite use of the word 

 ' type ' aud its compounds, as denoting specimens 

 of a greater or less degree of authenticity, by Old- 

 field Thomas. Proc. Zool. Soc. London, 1893, pp. 

 241-2. 



