42 Psyche [April 



existence in his later works, as if ashamed of the curious meaningless 

 names of his first publication. The diagnoses are brief, general and 

 ambiguous, and, since no species are mentioned the identity of the 

 genera would have remained mostly unknown, were it not that some of 

 the early descriptions bear a similarity to the corresponding ones of the 

 later paper. In nearly all cases however the generic names of 1800 

 are entirely different from those Meigen later used. The genera of 

 Meigen's second contribution are well known, as for most of them 

 typical species were cited at the beginning, and their names have been 

 in constant usage for our commonest flies for more than a century. 

 Even by this method of comparison and elimination many of the 1800 

 genera will never be understood. 



This early publication of Meigen remained entirely ignored until 

 Dr. F. Hendel republished it entirely in the Verhandlungen of the 

 Wiener Gesellschaft. If we were to accept his guesses as to the identity 

 of these early genera we would overthrow such well-known names as 

 Ceratopogon, Odontomyia, Eristalis, etc., as well as the long established 

 type-genera of over a dozen families of diptera. But much of his 

 evidence is insecure. The paper is worthless if not interpreted by 

 Meigen's later works, the date of publication cannot be verified, there 

 is even doubt if the pa])er was distributed on the date it bears, and 

 nowhere are any species cited, so the genera are not true binomial 

 conceptions. This last condition alone should not be followed too 

 closely, for many of IVIeigen's genera of 1803 and 1804 were likewise 

 published without mention of species. 



Naturally to exhume these forgotten names has stirred up much 

 discussion, and in the short interim since Hendel's republishing, there 

 have been a score of opinions given out by various biologists. These 

 opinions are sometimes conflicting but in the main zoologists strongly 

 decry using the law of priority to bolster up such speciesless genera as 

 Meigen's earliest. I shall give a list of the articles that have come to 

 ray notice bearing directly or indirectly on the principle of whether or 

 not to adopt the newly disinterred genera. In this long parley the 

 concrete example of JMeigen's paper has been lost sight of by many 

 of the contributors, and merely the principle has been under discussion, 

 but nevertheless the entire argument outlined below Avas caused by 

 the appearance of Hendel's reprint. A short digest of the articles 

 will help to correlate the ideas advanced. 



Professor Aldrich wrote in hopes of squelching Hendel's paper, to 



