414 HISTORICAL GEOLOGY. 



(4) The Vegetable Kingdom is a provision for the storing away or niagazining of force 

 for the Animal Kingdom. This force is acquired through the sun's influence or forces acting 

 on the plant, and so promoting growth ; mineral matter is thereby carried up to a higher 

 grade of composition, that of starch, gluten, vegetable fiber and other products, and in 

 this there is a concentration or accumulation of force. To this stored force animals go for 

 growth and development ; and, moreover, the grade of composition is thus carried yet 

 higher, to muscle and nerve ; and this is a niagazining of force in a still more concentrated 

 or condensed state. 



(5) Plants, of some minute kinds, and the spores of some larger species (some Algse) 

 have locomotion, or a degree of contractility in certain parts that corresponds to an infini- 

 tesimal amount of mechanical power ; but the locomotive spores, as they develop, become 

 fixed, like the plants from ordinary seeds, and no increase of mechanical power accompa- 

 nies vegetable development. In animal development from the germ, on the contrary, 

 there is always an increase of power — an increase, in all, of muscular (mechanical) 

 power, and, in the case of species above the lower grade, of psychical and intellectual 

 power, — until an ant, for example, becomes a one-ant power, a horse a one-horse power. 

 Whence, an auimal is a self-propagating piece of enginery, of various power according 

 to the species. 



(6) In the plant, the root grows downward (or dark-ward) and the stem upward (or 

 light-ward), and there is thus the up-and-doion polarity of growth — the higher develop- 

 ments, those connected with the fruit, taking place above, or in the light. In the animal, 

 there is an antero-posterior polarity of power as well as growth — the head, which is the 

 seat of the chief nervous mass and of the senses, and the locus of the mouth, making the 

 anterior extremity. Consequently, there is in animals a connection between grade and 

 the greater or less dominance and perfection of the head extremity. An animal, as its 

 ordinary movements manifest, is preeminently a go-ahead thing. Even the inferior 

 stationary species, like the Polyp, show it in the superior power that belongs to the 

 mouth extremity. 



(7) Plants have no consciousness of self, or of other existences ; animals are con- 

 scious of an outer world, and even the lowest show it by avoiding obstacles. 



Erom the above diverse characteristics of plants and animals, it follows that, however 

 alike chemically are the germs of the two, they must still be, in their chemical nature, 

 fundamentally different. 



ANIMAL KINGDOM. 



The most prominent subdivisions of the Animal Kingdom are : — 

 I. Vertebrates; II. Invertebrates. 



These subdivisions are based on the presence in the former alone of a vertebral 

 column, with a bone-sheathed cavity along the dorsal side of the column for the great 

 nervous cord. This vertebral column in the embryo-stage and in many adult fishes is a 

 cartilaginous cord, called the notochord (from the Greek for hack and a gut chord of a 

 stringed instrument) , situated below and parallel with the spinal cord or nerve ; out of it, 

 as development and ossification proceed, the vertebral column is produced. In the sheath 

 of the spinal nervous cord, the dorsal spinous processes of the vertebrae are produced, 

 which more or less inclose the cord. The Invertebrates, besides having no vertebral 

 column within, have the chief nervous cord ventral in position and below the intestinal 

 canal instead of dorsal. 



The Vertebrates include, beginning with the highest : — 



Mammals Reptiles Fishes 



Birds Amphibians Leptocaedians 



All other species are Invertebrates. ^ 



