380 What are Animals and Plants f 



animals and plants, as contrasted with substances which are 

 neither the one nor the other ? ' It remains to say a few 

 words as to the second question — that concerning the rela- 

 tions of animals and plants, one to the other. 



At first sight nothing could seem more obvious than the 

 distinctness of animals from plants ; but a very little science 

 soon shows that to draw a distinction is not so easy a matter. 

 Elaborate and recondite distinctions have been, one after 

 another, drawn out, but these have, one after another, broken 

 down, until there remains no one character which can be at 

 the same time affirmed of all animals and denied of all plants 

 (or vice versa), while these two great groups remain such as 

 they are generally taken to be, the creatures known as 

 Protozoa bemg reckoned as animals ; that is, the lowest so- 

 called animals, the bodies of which are not constituted of 

 ' tissues.' 



Let us look at these distinctions, beginning with the most 

 obvious : — 



1. The first of these relates to external form. The pre- 

 dominant branching vegetal form is denoted by the word 

 ' arborescent,' but many species of the animals (allied to the 

 Corals) are arborescent also, while multitudes of the lowest 

 plants are more or less spheroidal, and some are worm-like in 

 figure. 



2. Secondly, locomotion is common to almost all ammals, 

 but some are permanently fixed, like plants, while certain 

 lower plants, especially in the earlier stages of their existence, 

 are actively locomotive. 



3. Animals generally live on more or less solid food, 

 which they take into an internal digestive cavity. All 

 animals, however, do not do this, notably the Entozoa, while 

 certain plants are said to more or less nourish themselves on 

 captured prey, as is the case with Venus's fly-trap and 

 Dioncea (the sun-dew), while others, as the Pitcher plants. 



