FUNCTIONS OF ANIMAL LIFE. 85 



germ ; and reasons will be hereafter given for the belief, that the germ is sup- 

 plied by the male parent, and that the female supplies only the materials for 

 its development. Here, as in the Nutritive processes, we find that the opera- 

 tions immediately concerned in this function, namely, the act of fecundation, 

 and the development of the ovum, are not directly influenced in any way by 

 the nervous system ; and that the functions of Animal Life are called into 

 play only in the preliminary and concluding steps of the process. In many 

 of the lower Animals, there is no sexual congress, even where the concurrence 

 of two sets of organs (as in the Phanerogamic Plants) is necessary for the pro- 

 cess ; the ova are liberated by one, and the spermatozoa by the other; and the 

 accidental meeting of the two produces the desired result. In many Animals 

 higher in the scale, the impulse which brings the sexes together is of a purely 

 instinctive kind. But in Man, it is of a very compound nature. The instinc- 

 tive propensity, unless unduly strong, is controlled and guided by the will, and 

 serves (like the feelings of hunger and thirst) as a stimulus to the reasoning 

 processes, by which the means of gratifying it are obtained ; and a moral sen- 

 timent or affection of a much higher kind is closely connected with it, which 

 acts as an additional incitement. Those movements, however, which are most 

 closely connected with the essential part of the process, are, like those of deglu- 

 tition, respiration, &c., simply reflex and involuntary in their character; and 

 thus we have another proof of the constancy of the principle, that, where the 

 action of the apparatus of Animal Life is brought into near connection with 

 the Organic functions, it is not such as requires the operation of the purely 

 animal powers, sensation and volition. Thus, then, as it has been lucidly 

 remarked, " the Nervous System lives and grows within an Animal, as a para- 

 sitic Plant does in a Vegetable ; with its life and growth, certain sensations 

 and mental acts, varying in the different classes of Animals, are connected by 

 nature in a manner altogether inscrutable to man; but the objects of the 

 existence of Animals require, that these mental acts should exert a powerful 

 controlling influence over all the textures and organs of which they are com- 

 posed." 



Functions of Animal Life. 



100. The existence of consciousness, by which the individual (le moi, in the 

 language of French physiologists) becomes sensible of impressions made upon 

 its bodily structure, and the power of spontaneously exciting contractions in 

 its tissues, by which evident motions are produced, have been already stated 

 to be the peculiar attributes of the beings composing the Animal kingdom. The 

 evident motions exhibited by some Plants, cannot be regarded as indicating the 

 existence of any psychical endowments in the beings included in the Vege- 

 table kingdom ; for they are usually to be referred without difficulty to the 

 action, either direct or indirect, of an external stimulus, upon a contractile 

 tissue ; and even where no such action evidently takes place, there is good 

 reason to suppose its existence. To refer, therefore, the movements of Vege- 

 tables to a nervous system, of which no traces can be found, still more to 

 suppose them endowed with consciousness and will, as some have done, is 

 to violate most grossly a well-known rule in philosophy, which cannot be too 

 steadily kept in view in prosecuting physiological inquiries nonfingere hy- 

 potheses. 



101. There are in Animals, however, many movements which are equally 

 dependent upon direct stimuli for their production. Such are (as we have 

 seen), even in the highest, the actions of the heart and of the alimentary canal. 

 These, in the lowest tribes, probably bear a much greater proportion to the 



8 



