Raymond — Amphion, Harpina, and Platymetopus. 377 



Art. XL. — Note on the Names Amphion, Harpina, and 

 Platymetopus • by Percy E. Raymond. 



After my recent paper on the Chazy Trilobites (Annals 

 Carnegie Museum, vol. iii, No. 2) was in type, Dr. W. J. Hol- 

 land called my attention to the fact that the name Amphion 

 was in general use for a common genus of moths. A little 

 investigation showed that not only Amphion, but Uarpina 

 and Platymetopus, two other generic names used in the paper 

 cited, were likewise preoccupied. 



The first use of Amphion as a generic name was by Hiibner, 

 who, in 1816, applied it to one of the Lepidoptera.* Pander 

 proposed the same term for atribobite, in 1830,f and designated 

 Amphion frontilob a = Asaphus Fiseheri Eichwald as the type. 

 Since Amphion is thus preoccupied, it becomes necessary to 

 find some other name to apply to this trilobite. Angelin, in 

 1851, % used Pliomera as a new generic designation for trilo- 

 bites of the type of Asaphus Fiseheri Eichwald, evidently 

 intending to restrict the genus to its original meaning. This 

 name Pliomera should now be adopted to replace the pre- 

 occupied name Amphion Pander. 



The Chazy species Amphion canadensis differs in several 

 particulars from the European form Pliomera Fiseheri. In 

 the American species the median furrow of the glabella is very 

 faint and frequently absent ; the second pair of furrows are 

 much further apart, thus producing one large frontal lobe 

 instead of two small ones as in the Russian species ; the facial 

 sutures reach the lateral margin in front of the genal angles ; 

 the frontal border is not denticulate, and the two species do 

 not have the same number of thoracic segments. 



The absence of the median glabellar furrow and of the 

 denticulate margin seem to be of considerable taxonomic impor- 

 tance, as this furrow cannot be regarded as due to the mechan- 

 ical effect produced by the enrollment of the animal in press- 

 ing the spinose tail against the glabella. This is proved by 

 the fact that no pygidial spine is situated opposite the median 

 furrow, but that the two median spines of the pygidium are 

 placed so that one comes on either side of the frontal furrow. 

 Again, the second pair of glabellar furrows are longer than 

 this median furrow, and the third set is still longer, as would 

 be the case if all were glabellar furrows. Finally, in Amphion 

 canadensis there is a smooth border around the front, and the 

 median indentation is almost obsolete, while the pygidium 



* Verzeichniss bekannter Schmetterlinge. 



f Beitrage zur Geognosie des russischen Beiches, p. 139. 



\ Palaeontologica Scandinavica, p. 30. 



