452 Miscellaneous. 



that shall be valid is the oldest, and not the one that has hitherto 

 been in use and is well known ; the consequence is that the species 

 are quoted under names some of which were never current, and 

 have to be explained by the addition of those previously used, since 

 their meaning is unknown ; the oldest name has the right of 

 priority. 



On this point Looss remarks in his latest work, ' On New and 

 Previously Described Trematodes from Marine Turtles ' (' Uber neue 

 und bekannte Trematoden aus Seeschildkroten,' Jena, 1902) : — "A 

 name has no right of priority unless accompanied by statements 

 by means of which the species in question can be re-identified. The 

 bare possibility that by an older name a certain species is meant to 

 be understood is not sufficient to justify its re-introduction ; the 

 right of priority can be claimed for an old name only when it is 

 recognizably defined, otherwise it is invalid, since the question 

 turns upon the meaning of the name. "With an exchange of names 

 there must also be connected an exchange of concepts ; the old 

 name must, in order to supersede the later one, be justified by its 

 meaning ; the introduction of old names to which no one is able to 

 attach a certain definition could ouly give rise to differences of 

 ojiinion." 



That this is to be demanded of generic just as much as of specific 

 names is self-evident J generic names that convey no meaning are 

 valueless. 



It is sad that there should be any necessity to lay stress upon 

 these self-evident principles ; we shall see, however, that it was 

 bound to happen, for modern systematists deal largely in words 

 that are wanting in meaning, and we are involuntarily reminded 

 of Goethe's 



" Denn eben wo Begrifte fehlen, 



Da stellt ein Wort zur recliten Zeit sich ein ; 



Mit Worten lasst sich trefflich streiten, 



Mit Worten ein System bereiten ; 



An Worte lasst sich trefflich glauben. 



Von einem Wort lasst sich kein Jota rauben " *. 



This is the answer that the foolish scholar receives to his 

 objection : — 



" Doch ein BegrifFmuss bei dem Worte sein " f. 



The word Fasciola is substituted for the well-known and 

 customary Distomum ; almost all authors loyally write Fasciolidae 

 instead of Distomidao, according to the law of priority laid down by 

 the Zoological Congress, 



* For just where ideas are wanting 



Comes in a timely word ; 



With words can we raise a rare dispute, 



With words a system institute ; 



Belief on words may we well bestow, 



No single jot will a word forego. 

 t Yet with the word an idea must be. 



