52 CODE OF NOMENCLATURE. 



anonym, nomen nudum, or mere name unaccompanied by diagnosis ; or 

 from the chironym, an unpublished manuscript name ; or from a pseudonym, 

 a nickname or vernacular name. The onyin is of two kinds ; \\\e graph any m, 

 resting upon a published plate, diagnosis, or description, and the typonym, 

 based upon indications of a type species or type specimen (see Canons 

 XLII., XLIIL). Onyms are further named mononyms, dionyms, trionyms, 

 or polyonyms, according to whether they consist of one, two, three, or more 

 words. (Cf. COUES, The Auk, I., Oct. 1884, p. 321.) 



CANON XLII. The basis of a generic or subgeneric name 

 is either (i) a designated recognizably described species, or 

 (2) a designated recognizable plate or figure, or (3) a published 

 diagnosis. 



REMARKS. Some writers insist that a generic or subgeneric name in 

 order to be tenable must be accompanied by a diagnosis. However proper 

 such a requisition may seem theoretically, the principle is thoroughly im- 

 practicable, and if enforced would lead to hopeless confusion. The custom 

 of naturalists has been quite otherwise, and the mere mention of a type has 

 been found to be often a better index to an author's meaning than is fre- 

 quently a diagnosis or even a long description. Either of the three alterna- 

 tives given above may alone be accepted as a proper definition. In the case 

 of a diagnosis, it must of course give some character or characters by which 

 the organism it is intended to designate may be unmistakably recognized. 



CANON XLIII. The basis of a specific or subspecific name is 

 either (i) an identifiable published description, or (2) a recog- 

 nizable published figure or plate, or (3) the original type speci- 

 men or specimens, absolutely identified as the type or types 

 of the species or subspecies in question ; but in no case is a 

 type specimen to be accepted as the basis of a specific or sub- 

 specific name, when it radically disagrees with or is contra- 

 dictory to the characters given in the diagnosis or description 

 based upon it. 



REMARKS. It therefore follows that a specific or subspecific name rest- 

 ing on a description which was originally so vague as to render the name 

 indeterminable, or which has become so through the later discovery of closely 

 allied species, may be established by reference to an authentic type speci- 

 men, when such exists ; but if the description proves to be so glaringly erro- 

 neous as to present characters contradictory to the type specimen, the type 

 specimen is not to be taken as the basis of the name ; the name in such case 

 is to be ignored or treated just as it would have to be if no type specimen 



