species of identical generic characters," whicb indicates that generic char- 

 acters originate independently of the specific* 



The classification of the present list is illustrated by the above remarks. 

 I now briefly allude to the rules I have followed in adopting a nomen- 

 clature. These rules are those in general use in the United States, as 

 based on the revision of the rules of the British Association for the 

 Advancement of Science by a committee of the American Association, 

 and elaborated in more detail by W. H. Edwards,t after Thorell aud 

 Wallace ; in other words, the law of priority is followed under the fol- 

 lowing definitions : 



(1) A specific name given by an author must relate to a description 

 or plate of the object intended. 



(2) A generic name of a species must be accompanied by a separate 

 definition of the genus intended, by reference to some of its distinctive 

 features. 



Note. — These two rules are properly regarded as the safeguards of 

 nomenclature, since they ofter the only means by which the writings of 

 authors in the sciences concerned can be intelligible. The necessity of 

 these rules will become increasingly apparent, since, as the systematic 

 sciences become more popular, sciolists may publish pages of names in 

 any of their departments, with the efi'ect, should such names be author- 

 itative, of indefinitely postponing the cultivation of the subject. A 

 generic diagnosis is not necessarily perfect in the early stages of the 

 classification of a science, and may be found later to embrace more than 

 one generic type J hence, the following additional rule has been found 

 necessary : 



(3) In the subdivision of a genus, names of the new genera are to be 

 adopted in the order of priority of the definition of the divisions to which 

 they refer; the remaining natural generic group retaining the original 

 name, unless the latter has been already given to one of the divisions, 

 as prescribed. 



(4) Prloritj^ reposes on date of publication, and not on date of read- 

 ing of papers. 



Of course, consistently with the above rules, as divisions of high rank 

 must be defined in order to be understood, names of these unaccompa- 

 nied by definitions are not binding on the uomenclator. 



In regard to orthography, the same code of rules has been followed, 

 viz, in the Latinization of all words of Greek derivation. This has been 



* Origin of Genera, Pliiladelphia, 1868. 

 t The Canadian Entomologist, 1873, p. 32. 



