]Sotes on Nomenclature. 91 



We have waited for nearly a hundred years to ascertain 

 what we mean when we use tlie generic name Lycosa, and 

 if we are to make a new genus every time we want to settle 

 the type of an old one, it seems likely that we shall wait for 

 another century. 



On account of Inadequate Diagnoses. 



In very many cases, moreover, generic diagnoses contain 

 only characters which apply equally well to the wliola family; 

 and still more noticeable is the fact that there are often plenty 

 of excellent characters on which genera could be based which 

 were never even observed by the authors who founded the 

 divisions, and do not occur in the diagnoses. 



As notable instances of this, one may refer to the minute 

 diagnoses of genera and species made by Dr. Thorell in his 

 study of the Scorpiones. It is not possible to tell from those 

 diagnoses even the family to which the species described 

 belonged, because the one character on which the division 

 into families can be satisfactorily based was overlooked. So, 

 too, in the case of the Aviculariid£B. The subfamily divisions 

 are now based upon characters of which, except in two cases, 

 the very existence was not noticed — namely, the organs of 

 stridulation. 



So that unless there are definite type-species to refer to, it 

 is not possible to make any further progress in systematic 

 knowledge. We continue to muddle on, checked at every 

 point by inadequate diagnoses. But directly we have a type- 

 species selected for each generic name we are in a position 

 to judge of the value of the divisions indicated by those 

 names, and also of others which we may ourselves contem- 

 plate. We can refer to the facts and see for ourselves, and 

 we shall not then be making new generic appellations on the 

 strength of newly-discovered characters, when there are 

 probably plenty of names already available, if we could but 

 examine definite types. We want to classify our material 

 according to the facts we find in Nature, not by the concepts 

 to which we are restricted by a study of the diagnoses printed 

 in literature. I may remark, too, that type-species of genera, 

 unless thev happen to be unique, can always be freely inter- 

 exchanged, and thus some progress in the science made. 



As a concrete illustration of a practical difficulty arising 

 for the systematic zoologist, I would suggest that anyone 

 who doubts the value of definite type-species should secure 

 a collection of 500 species of the Salticida3, for instance, and 

 endeavour to classify them by the light of original generic 



