A discussion of certain questions of nomenelatiire, as applied to parasites. 187 



influence exercised upon him by his study of the value of characters 

 in other groups, to existing necessities of a practical nature — such 

 as technique of the subject, and to other factors. 



Taking all these points into consideration, while I do not under- 

 estimate the convenieuce of the diagnosis, it does not appear un- 

 reasonable to say that it is raore of a convenience than a neces- 

 sity, while the type is both a convenience and a necessity. 



I am unable, therefore, to fully agree with Looss in the view he 

 implies, perhaps, more than expresses, a view certainly definitely ex- 

 pressed by many authors, that the diagnosis is more important than 

 •the type — a view, further, which admits that something ephemeral 

 is more important than something permanent. I find it necessary, on 

 the contrary, to give the type the first place of importance in con- 

 nection with a generic name, and I should much prefer to deal with 

 a large uumber of generic names established on known species as 

 types, than a large number of names established only on diagnosis, or 

 on long anatoraical and histological descriptions not reduced to diag- 

 noses. This should not be construed as meaning that I undervalue 

 the convenience of a diagnosis; quite on the contrary, it should 

 always be given in proposing a new genus; but we must not forget 

 that every published diagnosis is to a large degree, subjective, hence 

 ephemeral, while every published type is absolutely objective, hence 

 permanent. 



While not [losing sight of the abstract consideration involved, 

 authors may unite upon a practical compromise by considering the 

 type and diagnosis as coordinate. 



III. In proposing a new specific name. 



, 1) Give a diagnosis, both specific and differential, or refer clearly 

 to the name for which it is substituted. 



2) Having selected a specific name, look up all the specific names, 

 valid, available, and unavailable, already proposed for the species 

 be longing to the genus in question, and also the specific names used 

 in combination with homonyms of the generic name in question. 



If, for instance, we have a genus X-us 1840 in Trematodes, with 

 a homonym X-us 1850 in another group, as birds, and there exists 

 a bird with the name X-us alhus^ the specific name albus is not 

 available as a new specific name in the Trematode genus X-us. 



3) State in connection with the diagnosis where the type, cotypes, 



