OF INVERTEBRATE ANIMALS. 
399 
all that happiness and delight which his existence in this world is calculated to 
confer. 
There are two ways of arranging the objects in these kingdoms in a systematic 
manner. By one way, particular properties or qualities of objects are made the 
basis of arranging them into a system. This method is artificial, and although 
founded on natural properties, yet, taking only single properties into considera¬ 
tion, objects are often brought together which are very dissimilar in their real 
nature. Such systems are called artificial. The celebrated botanical system of 
Ltnnveus is “ a good illustration” of this mode of arranging natural objects, 
exhibiting both its advantages and defects. The other mode of classifying natural 
objects is by considering all the properties and qualities they may present, and 
by giving a proper relative value to each, to bring those objects together which 
most resemble each other in their real nature. These are called natural systems, 
and are the only ones by which science can be advanced. 
In looking at the three kingdoms of Nature, we find that they do not pass into 
each other by an ascending line, but that there is a central point from which 
each appears to start, and the further any individual of one kingdom may be 
removed from this point, the less does it resemble individuals in the other king¬ 
doms. But close to this central point it is very difficult to determine to which 
kingdom the objects belong. It is at this part of our plan that we must station 
those minute and, to the naked eye, invisible particles which are constantly 
moving about in water, and which may or may not be inanimate matter, or the 
germs of vegetables or animals. It is here we must refer those inscrutable beings 
called “first plants” and “first animals” (Protophyta and Protozoa ), which have 
caused so much perplexity to scientific observers, some thinking them all plants, 
others considering them all animals, whilst some again believe they begin their 
existence as plants, and finish as animals ; and others conceive they commence 
life as animals, and finish as plants. 
Amongst those beings which seem to claim a situation amongst animals on 
account of their movements is the Oscillatoria. There are, however, among the 
tribe of plants called Conferva many others which exhibit, both in their embryo 
and perfect state of existence, motions as singular as the Oscillatoria. Viva 
bullata is one of these; and the peculiarly fantastic movements of its germs or 
ovules are calculated to excite the greatest interest in this obscure part of the 
dominions of Nature. 
In tracing up the line of succession in the Animal Kingdom, it is difficult to 
know exactly at what point to begin, two or three of the lower groups of animals 
claiming in some characters a close relation to the Vegetable Kingdom. 
However,without entering into the various claims of these groups to be considered 
the lowest in the animal scale, I shall commence my observations on the Animal 
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