110 REPORT— 1842. 



The same reasons apply also to generic names. Linnaeus was the first to 

 attacli a definite value to genera, and to give them a systematic character by 

 moans of exact definitions; and therefore although the names used by pre- 

 vious authors may often be applied with propriety to modern genera, yet in 

 such eases they acquire a new moaning, and should be quoted on the author- 

 ity of the first person who used them in this secondary sense. It is true, 

 that several of the old authors made occasional approaches to the Linnaeau 

 exactness of generic definition, but still these were but partial attempts ; and 

 it is certain that if in our rectification of the binomial nomenclature we once 

 trace back our authorities into the obscurity which preceded the epoch of 

 its foundation, we shall find no resting-place or fixed boundary for our re- 

 searches. The nomenclature of Ray is chiefly derived from that of Gesner 

 and Aldrovandus, and from these authors we might proceed backward to 

 /Elian, Pliny, and Aristotle, till our zoological studies would be frittered 

 away amid the refinements of classical learning*. 



We therefore recommend the adoption of the following proposition : — 



§ 2. The binomial nomenclature having originated with Linnaeus, 

 the law of priority, in respect of that nomenclature, is not to extend to 

 the writings of antecedent authors. 



[It should be here explained, that Brisson, who was a contemporary of 

 Linnaeus and acquainted with the ' Systema Naturae,' defined and published 

 certain genera of' birds which are additional to those in the 12th edition of 

 Linnreus's work, and which are therefore of perfectly good authority. But 

 Brisson still adhered to the old mode of designating species by a sentence 

 instead of a word, and therefore while we retain his defined genera, we do 

 not extend the same indulgence to the titles of his species, even when the 

 latter are accidentally binomial in form. For instance, the Pcrdix rubra, of 

 Brisson is the Tetrao rufus of Linnaeus ; therefore as we in this case retain the 

 generic name of Brisson and the specific name of Linnaeus, the correct title 

 of the species would be Perdix rufa.~\ 



[ Generic names not to be cancelled in subsequent subdivisions.'] 

 As the number of known species which form the groundwork of zoological 

 science is always increasing, and our knowledge of their structure becomes 

 more complete, fresh generalizations continually occur to the naturalist, and 

 the number of genera and other groups requiring appellations is ever be- 

 coming more extensive. It thus becomes necessary to subdivide the contents 

 of old groups and to make their definitions continually more restricted. In 

 carrying out this process, it is an act of justice to the original author, that 

 his generic name should never be lost sight of; and it is no less essential to 

 the welfare of the science, that all which is sound in its nomenclature should 

 remain unaltered amid the additions which are continually being made to it. 

 On this ground we recommend the adoption of the following rule : — 



§ 3. A. generic name when once established should never be can- 

 celled in any subsequent subdivision of the group, but retained in a 

 restricted sense for one of the constituent portions. 



[Genei'ic names to be retained for the typical portion of the old genus. ~\ 



When a genus is subdivided into other genera, the original name should 



be retained for that portion of it which exhibits in the greatest degree its 



essential characters as at first defined. Authors frequently indicate this by 



selecting some one species as a fixed point of reference, which they term the 



* " Quis longo a?vo recepta vocabula commutaret hodic cum patrum?" — Linnaus. 



