November 23, 1900.] 



SCIENCE. 



785 



These are at present as follows : 



Nature of manufacture. Number of Number of per- 

 establish- sons em- 

 ments. ployed. 

 Astronomical, optical, mathe- 

 matical, physical and elec- 

 trical instruments 500 9,200 • 



Glass-blowing, glass instru- 

 ments, glass thermometers... 125 1,773 

 Optical instruments, specta- 

 cles, reading-glasses 165 2,652 



Total 790 13,625 



THE FIRST SPECIES NA3IED AS TBE TYPE 

 OF THE GENUS. 



In the suggestive article on ' The Method 

 of Types in Botanical Nomenclature,' by 

 Mr. O. F. Cook, published in Science of 

 September 28, 1900, is an admirable state- 

 ment of the meaning of type in biological 

 taxonomy. 



A species ' is a coherent or continuous 

 group of organisms.' Its type is the first 

 individual on which the specific name was 

 bestowed. The type-specimen has an espe- 

 cial value in fixing the name and meaning 

 of the species. 



In like manner • a genus of organisms is 

 a species without close afBnities or a group 

 of mutually related species.' In other 

 words, it too ' is a coherent or continuous 

 group of organisms.' It is essential to its 

 definition that some one of its species should 

 constitute its type, to which the generic 

 name should be inseparably attached. The 

 large genera of earlier writers, subdivisions 

 of their artificial orders, rather than groups 

 of species, must become each associated 

 around a special type before they can enter 

 into modern conceptsions of nomenclature. 



The first essential in nomenclature is 

 fixity. To establish permanence we must 

 eliminate all elements of personal choice. 

 The fixity of specific names through the 

 law of priority is now fairly well estab- 

 lished. Generic names are not yet similarly 

 fixed. The method of changing the con- 

 ception of an old genus from that of a mere 



subdivision of a higher group to that of 

 a group of related species associated about 

 a type species has not yet been well deter- 

 mined. In nomenclature, a genus must be 

 fixed by its type, which is definite, not by 

 its definition, which may be amended. 

 Some writers have insisted that the first 

 writer who subdivides a genus has the right 

 and the duty to fix its type. Others main- 

 tain that the type must always be fixed by 

 the process of elimination. In this process 

 authors who eliminated unconsciously or 

 in ignorance must be considered, as well as 

 those who attempted to limit and define the 

 generic parts in a group of family rank, 

 called by its author a genus. 



The method of elimination is now gen- 

 erally approved, but there is great variation 

 in the application of it. Its great defect 

 lies in the necessary uncertainty of its 

 definition. Too often different assumptions 

 or different points of view give different re- 

 sults. Any result may be vitiated by the 

 discovery of some note or discussion — use- 

 less in itself, which may have been over- 

 looked at the time of the first attempt at 

 finding the type. 



Inasmuch as the thought of type is in- 

 separable in modern taxonomy from the 

 idea of genus or species, it is most desirable 

 to find some way of fixing the type of an 

 author through the words of the author 

 himself — not trusting to the mazes of sub- 

 sequent delimitation and elimination. 



The most convenient and most logical 

 method of doing this, as well as the one most 

 practically convenient, is to fix a group 

 name to the first individual or the first spe- 

 cies to which the name was tenably applied. 

 If based on specimens, the species would rest 

 with the individual actually in hand for de- 

 scription. If based on a series of previous 

 records, the one of these standing first in 

 the list of synonyms should be the type. 



In the case of the genus, if no type, cen- 

 tral species or ' chef de file ' is indicated by 



