( xxvi ) 



self-evident tlmt we ask onrselvos in woiuler Ijow it is possible that there 

 are systeraatists who do not— should we sa}' will not ? — recognise the necessity 

 of it. If Fringilla coclebs is acceiitcd as a furmula for a species, Sphinx 

 atlaiiticun is also a designation of a species, and not of a genus or a variety 

 or a subspecies. To speak of " species " Sphinx ocellata and of " subspecies " 

 Sphinx atbniticits is a contradiction unworthy of science. 



In former times varieties were looked npou as freaks of nature. They were 

 to many a classifier an interesting nuisance, which often threatened to upset 

 the balance of his well-fixed species, and were on that account more often 

 entirely put aside tiian welcomed as an object for research. Esper, who went 

 jierhaps deejier into tlie plienomena of variation than most of his contemporary 

 entomologists, already distinguisiied between ordinary varieties (Abweichungen) 

 and abnormal individuals (Ansartungen). However, as long as the principle of 

 evolution underlying these varieties was not recognised, there was no need to 

 study them systematically, and to work out a system of nomenclature which 

 would bring into order the chaos of varieties, as did Linn(5's binominal system 

 the chaotic mass of sj)ecies. 



From Linn(3 onwards varieties, if provided with a distinctive name, are 

 recorded in various ways. The following names may serve as illustrations : 

 I'lipilio iris lutens ; Columba oenas /3. dometstica ; Fhasia/tiis gallus /3. gallus 

 cristafiis : Fhasianus colc/nci/s (/3.) rhimanus varius. The word varietas, 

 introduced by Liun(5 as subordinate to species, meant anything deviating 

 obviously iVom the normal individuals of a sj)ecies. The practice of putting the 

 term in an abbreviated form, as rarit-t. or var., before the varietal name does 

 not seem to have sprung up before the beginning of the nineteenth century, 

 and the use of the term aberratio {ab. = aberr.) is still younger. Not rarely 

 the " variety " was in reality the normal form, while the " species " happened 

 to be described from aberrant specimens. There was no strict rule for the 

 emi)loyment of rar. or ab. ; some treated well-marked varieties as var. and less 

 obviously different individuals as ab., the distinction between mr. and ab. being 

 merely quantitative ; wliile others employed ab. for abnormal specimens occurring 

 singly among the normal ones, and var. for the regularly observed varieties. 

 There are many collectors and classifiers, representing the stagnant element 

 in this dejiartment of our science, who look at varieties still from either of 

 these standjioints. 



Since the middh' of the last century, when natural science stepped from 

 childhood into maniiood, the study of variation has gradually become more 

 methodical, with a change in the 



PRINCIPLES OP CLASSIFICATION, 



and has now attained a Jiiight of which our forefathers in science did not dream. 



New lines of research bring to light new series of facts ; and new kinds 



of facts require a new terminology. It will not do to have the same 



nomenclatorial formiihi for a s]iecics as for a genus ; and so it will also not 



