july — sept. 1857.] The Vohox Globator. 



SOT 



spontaneous motion or more properly locomotion. But this was 

 soon seen to be insufficient for most of the Polypes and some of 

 the Echinodermata ; all Cirripedes ; and even some of the higher 

 orders — the Scrpula among Articulata and the Oyster among 

 Molluscs are fixed to the rocks on which they grow. 



On the other hand the Spores of many Algce is of Vaucheria and 

 of the Sponges have a very rapid locomotion. 



The next distinction attempted to be drawn was taken from the 

 mode of deriving nourishment, "plants" it was said "absorbing 

 " nutriment by means of fibres at the lower extremity of the body, 

 " animals by an opening (or mouth) at the upper end, conducting 

 " to a capacious sac" (or stomach.) 



But the Grcgarina, a genus of microscopic parasites infesting 

 gregariously the intestinal canals of insects, worms, Sec. and seve- 

 ral of the free Infusoria have neither mouth nor stomach and 

 there is no stomach in Cesioidea one of the larger Entozoa. They 

 are supposed to derive nutriment by absorption through the skin. 



A third characteristic was supposed to have been found in the fa- 

 culty possessed by plants of exhaling oxygen whilst animals expire 

 carbonic acid. Butliere too the distinction fails ; some of the free 

 moving Polygastria eliminate pure oxygen in one stage of their 

 existence while Mushrooms and Sponges have been found to give 

 out pure carbonic acid gas. 



Another chemical distinction it was thought had been discover- 

 ed in the quaternary composition of animals which are resolvable 

 into carbon, oxygen, hydrogen and nitrogen, whereas owing to the 

 absence of the last mentioned element, the constitution of plants 

 is ternary. Cellulose indeed is a binary compound of carbon and 

 hydrogen only. But neither does this definition hold. Nitrogen 

 is found in Algce, Fungi and most cryptogamous plants. And on 

 the other hand, the mantle of Frustulia a mouthless Polygastria 

 and the thick cellular coat of Ascidia are binary compounds. Mr. 

 Bidie has shown that there is reason to suppose the same binary 

 constitution is not unknown among the highest order of animal ex- 

 istence, in the brain of Mammalia. 



