232 GENERAL VIEW OF THE FUNCTIONS. 



having a purpose distinct from that of the rest. Such a fabric is considered 

 as a very heterogeneous one ; and is eminently distinguished from those homo- 

 geneous organisms, in which every part is but a repetition of the rest. Of all 

 Animals, Man possesses, as already shown, the greatest variety of endow- 

 ments, the greatest number of distinct organs ; and yet Man, in common with 

 the simplest Animal or Plant, takes his origin in a single cell. It is in the 

 almost homogeneous fabrics of the Cellular Plants, that we find the closest 

 connection between the function of Nutrition, and that of Reproduction ; for 

 every one of the vesicles which compose their fabric, is endowed with the 

 power of generating others similar to itself; and these may either extend the 

 parent structure, or separate into new and distinct organisms. Hence it is 

 sca'rcely possible to draw a line, in these cases, between the Nutrition of the 

 individual, and the Reproduction of the species. 



282. But, it will be inquired, how and where in the Human body (and in 

 the higher Animals in general) is this embryonic vesicle produced, and what 

 are the relative offices of the two sexes in its formation ? This is a question 

 which must still be answered with some degree of doubt; and yet observed 

 phenomena, if explained by the aid of analogy, seem to lead to a very direct 

 conclusion. The embryonic vesicle itself, like other cells, must arise from a 

 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 Ani- 

 mals 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 

 instinctive 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 sentiment 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 deglutition, respiration, <fec., 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 Ani- 

 mal, as a parasitic 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 ob- 

 jects 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 composed." 



3. Functions of Animal Life. 



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

 the language of French physiologists) becomes sensible of impressions made 



