PRINCIPLES, CANONS, AND RECOMMENDATIONS. 53 



existed ; and the species is lo be reintroduced into science under a new 

 name, as a new species, and with a proper description. 



The authenticity of a type specimen is often a matter of the highest im- 

 portance. The evidence will vary in different cases ; it may be merely 

 circumstantial, but of such a nature as to be positive in character ; or the 

 specimen may bear a label in the handwriting of the original describer signi- 

 fying it to be his type; or the history of the specimen may be so well known 

 to those having it in charge that there can be little reason for doubt in the 

 matter. But tradition, in the general sense of the term, cannot be regarded 

 as satisfactory evidence ; and nothing short of the written statement of the 

 author, securely attached to the specimen, affirming it to be the type, should 

 in future be considered satisfactory evidence. Still, this requirement cannot 

 be insisted upon for the past, since in few cases have types been heretofore 

 thus designated, though their authenticity may be in many cases beyond 

 cavil. Your Committee would recommend that in future authors should not 

 only specify their types in their descriptions, and label them as their types, 

 but should designate the collection in which they are deposited. 



CANON XLIV. In determining the pertinence of a description 

 or figure on which a genus, species, or subspecies may respect- 

 ively rest, the consideration of pertinency is to be restricted to the 

 species scientifically known at the time of publication of the de- 

 scription or figure in question, or to contemporaneous literature. 



CANON XLV. Absolute identification is requisite in order 

 to displace a modern current name by an older obscure one. 



REMARKS. -- The purpose of the foregoing rules (Canons XLIII.-XLV.) 

 is to check the tendency to replace current names by earlier ones, the 

 identification of which may be determined only by a process of elimination 

 on the ground that they can relate to nothing else based on our pres- 

 ent knowledge of Zoology, but which cannot be determined from the imper- 

 fect description given by the original describer, alone or supplemented by the 

 contemporaneous literature of the subject; in short, the identification of 

 which rests on our present knowledge of the species inhabiting the assigned 

 habitat of the form in question. 



CANON XLVI. In describing an organism which is consid- 

 ered to represent a new genus as well as a new species, it is not 

 necessary to formally separate the characters into two categories, 

 generic and specific, in order to render tenable the names given 

 to the organism in question, although such a distinction is 

 desirable. 



