100 E VOL UTION AND DOGMA. 



microphytes, and their congeners. Here classifica- 

 tion is at best provisional and arbitrary, and depends 

 entirely on the point of view from which they are 

 studied. In such lowly forms of life, not only is the 

 certain discrimination of species impossible, but it is 

 impossible even to draw a hard and fast line between 

 what is incontestably animal life on the one hand, 

 and vegetable life on the other. 



Such being the case, what, it may be asked, be- 

 comes of species? What of classification? What of 

 the various systems which have been proposed ? 

 Have species any real existence, the question is 

 again asked, or are they but mere figments of the 

 imagination, ignes fatui, which have ever eluded the 

 grasp of the investigator, and which are now even 

 farther away from it than they ever were before? 

 Are they but varying, metaphysical entities, airy 

 nothings, convenient only for purposes of specula- 

 tion and for a classification which, from the very 

 nature of the case, must at best be but provisional 

 and arbitrary ? 



In reply to these questions it may be stated that 

 there are still those, and their number is far from 

 being small, who yet cling to the old idea of species 

 as something real, immutable, and always recogniza- 

 ble. The instances I have just alluded to may not 

 indeed, it is conceded, exhibit all the specific definite- 

 ness of the Venus' flytrap, or the pearly nautilus, 

 but nevertheless, it is contended, the species exist, 

 despite the difficulties which obscure their definition, 

 or which, for the time being, make their recognition 

 impossible. 



