LEOYTHIL'M. 103 



A study of the literature relating to this genus, 

 first named Pamphagus by Bailey, has led the assistant 

 author of the present work to the conclusion that the 

 name which should be applied to it is Lecythmm. 

 That Pamphagus was pre-occupied was detected by 

 Averintzeff .as stated by Schouteden in his annotated 

 abstract in French* of Averintzeff's Russian memoir 

 of 1906 on the testaceous freshwater Rhizopoda 

 (Conchulina), in which Averintzeff had used the name 

 Pamphagus. Later in the same year, however, he 

 sent to the ' Zoologischer Anzeiger ' a paper in which 

 he proposed for Pamphagus the name Bailei/a, but 

 although received by the Editor of that journal in 

 October, 1906, it was not printed until February, 1907, 

 Schouteden thus being the first to publish the name. 

 Had no other name been applied to any species of the 

 genus this would have been very appropriate, but 

 between 1853, when Bailey named it, and 1906, when 

 Schouteden published a name in his honour, several 

 generic names had been given to one or other species 

 now included in the genus, and it is necessary to con- 

 sider them. 



We may at once dismiss three names used before 

 1853 : Arcella by Ehrenberg, Gromia by Schlumberger, 

 and Cori/cia by Dujardin, each founded for species 

 which do not belong to this genus, and the last one 

 cited being pre-occupied. A difficulty arises with the 

 next name to be mentioned, Plagiophrys. It was 

 founded by Claparedeand Lachmannfor a genus which 

 they describe as " Actinophyrens non cuirasses, munis 

 de nombreux pseudopodes, qui naissent en faisceau d'un 

 seul et meme point de la surface du corps. . . . Ces 

 pseudopodes laissent voir a leur surface la circulation 

 de granules caracteristique, qui est toutefois fort 

 lente." This is clearly not a definition of the present 

 genus, but how a rhizopod without any test could 



* The passage is as follows : " M. Awerintzew a propose dans le Zoolog. 

 Anzeiger le nom Bailey a pour le genre Pamphagus, ce dernier nom etant 

 preoccupe (Insectes)." This was published in the 'Annales de Biologie 

 lacustre ' in December, 1906. 



