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THE AMEBIC AX NATURALIST [Vol. XLIII 



similar objects, associated for convenience sake with a 

 single appellation; or as correlated, genetically unified 

 groups, as segregated portions of reality (convenient or 

 inconvenient for our intelligence) which nature somehow 

 sets apart, regardless of whether we know and name them 

 or not? To the writer it seems a matter of the first im- 

 portance. If organic nature is so fluid that our distinc- 

 tions are conventional only, if specific names are hut 

 handy helps by which we point out this or that sizeable 

 mass of organic territory, then must our whole attitude 

 be altered accordingly. It is no wonder that those who 

 hold this view are satisfied with nothing short of a general 

 knowledge of a whole fauna or flora. But if species are 

 downright realities (as science counts reality), subtle, 

 illusive realities, perhaps, still less than half understood, 

 yet existent, demanding ever more exact definition and 

 deeper explanation, then their knowledge becomes a new 

 and better thing, and the impetus they offer to investiga- 

 tion is wholly changed. Then must we recognize the right 

 to modify Linnasan species whenever they disagree with 

 reality, however much we respect Linmean authority. 



The whole spirit of modern biological research seems 

 to the writer to demand the conception of species as 

 realities, -not all alike, in their reality, of course. Lin- 

 naean species, elementary species, physiological species, 

 ontogenetic, phylogenetic species,— these and more may 

 well prove to be essentially unique phases of nature's 

 reality. But does not the thought of the investigator 

 that steadies itself by these conceptions of species as 

 realities fully justify itself by results? 



And if there are other reasons for the assertion of the 

 n'lreality of species, over and above the return to that 

 child-like thought which sees reality only in the obvious 

 units of perception, over and above a carelessly exag- 

 gerated idea of variation as obliterating all but conven- 

 tional distinctions, what, we ask, are they! 



