373 REVIEWS. 



ance that if the difference in climate, etc., between Kansas and 

 Pennsylvania has differentiated S. neglecta from S. magna, greater 

 yet parallel discrepancies in physical conditions have not in the 

 course of time changed 3'ellow to red, and made TriqnaUs out of 

 Sturnella. Refusing to name one short offset, we must refuse to 

 name another, if a longer one; and must add Tr ' ' '■' : "T'^iyis 

 to the synonyms of Sturnella ^Magn a. The lust;. i)0- 



cies " (which are practical^ our units of zoological coBaputation) 

 once admitted — and it is admitted by leaders in all branches of 

 natural history — it becomes a logical necessity to admit a corre- 

 sponding instability of all groups based upon an aggregation of 

 these units ; and if we are not to name Sturnella neglecta, because 

 it is only a little differentiation of S. magna, we cannot consist- 

 ently name a king-crab because it is great differentiation of a 

 trilobite. All differentiations are or were once, gradual and im- 

 perceptible ; all are of degree only, not of kind ; to name, or not 

 to uatae, is a matter of individual discretion. Mr. Allen's plan, 

 fully carried out, renders our nomenclature simply an index of our 

 skill or luck in tracing links between species ; and if our efforts 

 could be commensurate with his enthusiasm, we could not eour 

 sistcfiitly name auything. 



To our mind, this foix-ibly illustrates the inefficiency of the Lin- 

 nsean nomenclature as an adequate method of formulating our 

 knowledge. It answered, when a thing was either square or else 

 it was round — when species were held for fixed facts as separate 

 creations ; but now that we know a thing may be neither square 

 nor round, but something between, it is lamental^ly defective. 

 Not many years hence, we trust, naturalists will have discarded it 

 for some better method of notation ; and then the wonder will be 

 that we advanced so far with such a stumbling-block in the way. 

 Wlio shall say how much the advance of chemistry, for instance, or 

 of philosophic anatomy, has been facilitated, or indeed rendered 

 possible, by the invention of expressive symbols and apt formulas? 

 or how much of the acknowledged confusion in zoology and botany 

 flows from our cramped method of expressing our views ? If we 

 must continue to use a tool so blunt and unhandy as the binomial 

 nomenclature, all cannot be expected to use it with equal skill and 

 effect. — Elliott Coues. 



