254 Mr. H. T. Wharton on the proper Generic 



Genera of Birds, ed. 1^ p. 54, 18i0; Hand-list, ii. p. 181, 

 1870) P. major as the typical species, at another (Cat. of 

 Genera & Subg. of Birds contained in the Brit. Mus. p. 91, 

 1855) P. martins ; and Koch, one of the earliest to sub- 

 divide the group (/. c. infra, 1816), agreeing with Cabanis 

 and Heine, held P. viridis most worthy of the honour. 



Obviously, then, a strict application of the " Rules for 

 Zoological Nomenclature,-'^ which long ago received the im- 

 primatur of the British Association, is imperatively necessary ; 

 and the result fortunately is of no doubtful import. 



Now rule 3, " A generic name, when once established, 

 should never be cancelled in any subsequent subdivision of 

 the group, but retained in a restricted sense for one of the 

 constituent portions,^^ demands that some species or group of 

 species should still bear the distinctive generic name Picus. 

 This every one would nowadays grant. 



Rule 4, " The generic name should always be retained for 

 that portion of the original genus which was considered 

 typical by the author," is, however, what the whole question 

 strictly turns upon. Certainly it is not in many cases evident 

 that Linnaeus had any ever-present idea of what we now 

 mean by a type at all — 



" A primrose by a river's brim 

 A yellow primrose was to him, 

 And it was nothing more." 



But here we have a case which may be stated syllogisti- 

 call)^, thus : — 



Picus, meaning any Woodpecker, was held sacred to Mars ; 



Linnaeus called the Black Woodpecker Picus martius : 

 .•.he meant P. martius to be taken as the typical Picus. 



And the case is by itself so preeminently typical that it 

 may well be specially discussed. 



The mythological history of Picus is a very curious one. 

 Among the Romans — and he appears to have no Greek coun- 

 terpart — he was held as a divinity of no mean degree ; for 

 Saturn was his father, and Faunus was his son. As a famous 

 soothsayer, he made use of a Woodpecker in his auguries ; 

 indeed the fable ran that he was himself turned into a Wood- 



