NOMENCLATURE OF THE RHYNCHOTA, ETC. 27 



Linn. Geofifr., and Cicada for Tetigonia, Geoffr. ; this reverse- 

 ment does not affect the type-fixations in either of these, or in 

 any other, genera. 



4. By the statement of any subsequent author that "X" is 

 the type of a certain genus, provided that it be one of the original 

 species of that genus, and that such fixation be permissible by the 

 previous operations of other authors. 



Ex. 1. Cercopis, Fabr., 1775, type xpiunaria (Linn., 1758), 

 Latr., 1802. 



Ex. 2. The type of Memhracis, Fabr., 1775, is stated by its 

 author (in 1803) to be atrata, but this statement is invaUd, as 

 atrata was not an original species. 



N.B. The description (or mention with sufficient reference) of 

 one species only in a genus, in a general systematic work [such 

 as Amyot and Serville's ' Suites a Buffon, Hemipteres '] , is a 

 valid indication of the type ; this does not hold however in a 

 faunistic work, nor in works published previous to 1794. When 

 two or more species have been described or indicated in such a 

 work, the type should be subsequently founded on one of those 

 species. Where (as for example in Amyot and Serville) one 

 species, (say) " striata," is described, and the authors say "add 

 ' macidata,' ' venusta,' ' irrorata,' &c.," ' striata ' should be the 

 type. 



The following considerations also come under this heading : — 



a. Many authors consider that a name only (or even a 

 figure !) is sufficient to establish a genus. This does not appear 

 to me to be reasonable. The essential for the establishment of 

 the validity of a genus is surely a description, however short, 

 displaying the salient characteristics whereby it differs from its 

 nearest allies. Now take the case of (say) Laternaria, Linn., 

 1764 ; a name only, without a line of description. To find out 

 in what way Laternaria essentially differs from Cicada, 1758, 

 one would then have had to prepare a table of the species of the 

 former and compare it with a similar one of the remaining 

 species of the latter ! This, I contend, is not the establishment 

 of a genus. In the second case, a figure in the Atlas of 

 Belanger's Voyage to the East Indies (Insects by Gueriu) is the 

 warrant for the genus "' Eurijptera " (dropped in the letterpress 

 by Guerin himself).* 



/3. Subgenera are here treated for nomenclatorial purposes 

 as genera — that is to say, a subgenus on being raised to full rank 

 dates from its first proposal as a subgenus. The typical sub- 

 genus [i.e. that which contains the type of the genus) should 

 bear the same name as the genus. 



Ex. 1. Microvelia, erected by Westwood, 1834, as a subgenus 



* I also refuse to acknowledge the validity of a species based upon a 

 figure only, even though detailed. 



d2 



