280 



they have been relegated to the synonymy by certain European authors 

 because of the opinion held by a few dipterologists regarding the claims 

 to priority of the names of a recently resurrected paper by Meigen.* 



I have not used the generic names of that paper which are stated to 

 pertain to this family for the following reasons : Article XXV of the 

 rules governing zoological nomenclature adopted by the International 

 Zoological Congress states that a generic name unaccompanied by 

 cither a description or a figure is valid if the name of one or more 

 described species is mentioned as pertaining to it. Article XXX states 

 that the type of any polytypical genus is that one of the original species 

 which was first designated as such type, and that where there are two 

 species, one of which is subsequently cited as the type of another genus, 

 the remaining species shall be considered as the type of the old genus. 

 It will thus be seen that what really validates a genus is the indication, 

 by the author of the genus, of its type species, or the inclusion of a 

 species which may be cited by another author as the type even should 

 there be discrepancies between the type and the generic description. 

 Thus genera without species are invalid. By this ruling, misinter- 

 pretation of characters by careless workers is rectifiable; whereas if 

 genera were to be erected by mere description, fanciful interpretations 

 might seriously interfere with entomological or other scientific work 

 necessitating accurate identifications. As none of Meigen's genera in 

 the paper referred to had species assigned to them, they are necessarily 

 invalid. Meigen himself did not use the names subsequently, nor were 

 they ever, as far as I am aware, mentioned by other authors until Hen- 

 del reprinted Meigen's paper in 1908.! 



In this connection Hendel endeavored to link up Meigen's names of 

 1800 wMth those used by the latter in 1803,^ suggesting that the names 

 of the 1803 paper now in common use be ranked as synonyms of those 

 of 1800. Irrespective of the fact that in very many cases the associa- 

 tion of the names in the two papers was merely a guess, I consider that 

 Mendel's action made the genera valid only from the date when he 

 placed a species in them and not from 1800. These names therefore 

 must be ranked as synonyms of the 1803 names and date from 1908. 

 In view, then, of existing rules of nomenclature the course I have taken 

 in dealing with this family is the only one possible, and it will be 

 adopted by me in dealing with other cases of synonymy connected with 

 Meigen's paper. 



*Noiivelle Classification des Moiifhos a fleux ailes. 1800. 

 tVerhaiidl. k. k. Zool.-Bot. Gesellsch., Wieii, Bd. .'58, p. 48. 

 UHiKcr Ma^., Bd. 2. 



