124 



ANIMAL. 



be confined to a few weeks, months, or years, 

 or be extended to centuries, we cannot tell. 



Nor is it only whilst endowed with all their 

 peculiar and inherent properties that organized 

 differ from unorganized bodies. No longer 

 manifesting their especial powers, organized 

 bodies begin to be disintegrated ; their con- 

 stituent elements, held together in opposition 

 to the laws of chemical affinity, become ame- 

 nable to these, and forthwith enter into new 

 combinations, which imply the utter destruc- 

 tion of the organization as it had been formed, 

 and hitherto preserved. Organized beings, as 

 they alone die, so do they also alone undergo 

 putrefaction a process nothing precisely si- 

 milar to which occurs in the inorganic world. 



From this review of the distinguishing pecu- 

 liarities of organized and unorganized bodies, 

 it appears that organization implies vitality, 

 and that organization and life are insepara- 

 ble conditions. It would be going too far 

 to say that they were synonymous terms : 

 organization is the mode of structure proper 

 to living beings ; life is the series of actions 

 they exhibit. And this in fact appears to be 

 about the least objectionable definition of life 

 than can be given : life is tlie series of actions 

 manifested by organized beings; would we go 

 farther, we must condescend upon an enumera- 

 tion of these actions, namely, incipience by 

 a genesis or creation ; temporary endurance as 

 individual by nutrition, and indefinite continu- 

 ance as species by reproduction, modification 

 during the term of existence known by the 

 title of age, and end by death, to which spe- 

 cific acts or phenomena must be added the 

 peculiar inherent power which living beings 

 possess of overcoming the general physico- 

 chemical laws that dominate the rest of the 

 universe. 



Thus far we have discussed and contrasted 

 the physical qualities and phenomena common 

 to organized or living beings at large, with 

 such as inhere or are manifested by unorganized 

 bodies generally, more especially minerals; we 

 have still left untouched those that severally 

 pertain to the two grand divisions of the or- 

 ganized world, and that are peculiar to each 

 living thing individually; and here we shall 

 find that the manifestations of vitality are al- 

 most as various as the species that people the 

 earth. In the same manner as we have hitherto 

 gone on contrasting first the material compo- 

 sition, and then the actions of organic and 

 inorganic bodies, we shall still proceed by 

 comparing the material composition and the 

 capacities of action of the different classes of 

 organized beings first, and next of the several 

 individuals composing these classes one with 

 another. 



COMPARISON OF ANIMALS AND VEGETABLES. 



Animals and vegetables were longheld essenti- 

 ally and irreconcilably distinct from one another. 

 \Ve have already had occasion, however, to 

 observe in how many particulars they are iden- 

 tical. The material composition of both is often 

 in opposition with the general physico-chemical 

 laws, both are made up of a combination of 



solids and fluids, both consist of a variety of 

 heterogeneous parts, and both have determinate 

 sizes which they cannot exceed. Moreover, 

 both are possessed of vitality, in other words, 

 both commence by a genesis, preserve them- 

 selves as individuals by nutrition, and as spe- 

 cies by reproduction ; both grow by intus-sus- 

 ception, undergo the mutations which are 

 denominated ages, endure for a time, present 

 themselves in health or labouring under disease, 

 and both decay and die. How intimately ani- 

 mals and vegetables are associated, how nearly 

 they resemble one another, will farther appear 

 as we advance in the following 



Comparison of the general physical qualities 

 and material composition of Vegetables and 

 Animals. As a general axiom the material 

 constitution of vegetables may be said to be 

 less complex than that of animals; this at least 

 is more especially the case as the individuals 

 at the top of the two scales are concerned. 



No distinguishing feature of either class is 

 derivable from general diversity of Size. Be- 

 tween the microscopic lichen and infusory ani- 

 mal, and the gigantic adansonia and whale, 

 plants and animals of every intermediate mag- 

 nitude are encountered. 



Neither is there much to be said upon the 

 differences which vegetables and animals pre- 

 sent when their Forms are contrasted. The 

 forms of many are alike amorphous, or simply 

 globular ; certain pulverulent fungi in the one 

 class, and monads in the other, resemble each 

 other greatly. Among both, individuals also 

 occur whose parts are disposed around a centre ; 

 yet we do not advance far before we discover a 

 peculiarity in animals, namely, composition by 

 the union of two similar or symmetrical halves 

 along a middle line or axis, nothing similar to 

 which has even been imagined in the vegetable 

 world, the members of which on the contrary 

 often exhibit a horizontal division, but without 

 anything of symmetry, into root and branches. 

 As a general law the animal kingdom may be 

 said to affect the globular or simply produced 

 form, with radii in the shape of extremities 

 sent off from a central part ; the vegetable to 

 exhibit a greater tendency to ramification or 

 division into branches. 



In point of chemical composition animals 

 and vegetables consist very nearly of the 

 same elements: oxygen, hydrogen, carbon, 

 nitrogen, phosphorus, sulphur, iodine, bro- 

 mine, chlorine, potassium, sodium, calcium, 

 silicium, magnesium, manganese, and iron 

 have been detected in both ; aluminium and 

 copper have hitherto only been discovered in 

 vegetables, and fluor only in animals. But 

 these elements are united in each in very dif- 

 ferent relative proportions. Carbon predomi- 

 nates greatly in the more solid parts of vege- 

 tables, nitrogen in the bodies of animals gene- 

 rally, although to this rule there are many notable 

 exceptions ; albumen, fibrine, and gelatine all 

 contain much more carbon than nitrogen, and 

 certain fungi include a very large proportion of 

 nitrogen in their composition. Several ele- 

 ments, met with abundantly in animals, occur 

 but sparingly distributed among vegetables, 



