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as the man does, in a particle of nucleated protoplasm. 

 And in the lowest plants, as in the lowest animals, a 

 single mass of such protoplasm may constitute the whole 

 plant, or the protoplasm may exist without a nucleus. 

 Under these circumstances it may well be asked, how 

 is one mass of non-nucleated protoplasm to be distin- 

 guished from another ? why call one " plant " and the 

 other " animal ?" The only reply is that, so far as form 

 is concerned, plants and animals are not separable, and 

 that, in many cases, it is a mere matter of convention 

 whether we call a given organism an animal or a plant. 

 There is a living body called jEthalium septicum, which 

 appears upon decaying vegetable substances, and in one 

 of its forms, is common upon the surface of tan pits. 

 In this condition it is, to all intents and purposes, a fun- 

 gus, and formerly was always regarded as such ; but the 

 remarkable investigations of De Bary have shown that, 

 in another condition, the ALthalium is an. actively loco- 

 motive creature, and takes in solid matters, upon which, 

 apparently, it feeds, thus exhibiting the most character- 

 istic feature of animality. Is this a plant, or is it an 

 animal ? Is it both, or is it neither ? Some decide in 

 favor of the last supposition, and establish an interme- 

 diate kingdom, a sort of biological No Man's Land for 

 all these questionable forms. But, as it is admittedly 

 impossible to draw any distinct boundary line between 

 this no man's land and the vegetable world on the one 

 hand, or the animal, on the other, it appears to me that 

 this proceeding merely doubles the difficulty which, be- 

 fore, was single. Protoplasm, simple or nucleated, is 

 the formal basis of all life. It is the clay of the potter ; 



