ITS VITAL PROPERTIES, AND RELATIONS TO LIVING ORGANISM. 211 



mental organs certainly do not serve, in a lower degree, the same purposes as 

 are served by the homologous parts which are completely developed in other 

 species, or in the other sex. To say they are useless, is contrary to all we know 

 of the absolute perfection and all-pervading purpose of creation ; to say they 

 exist merely for the sake of conformity to a general type of structure, is surely 

 unphilosophical, for the law of unity of organic types is, in larger instances, not 

 observed, except when its observance contributes to the advantages of the indi- 

 vidual. No : all these rudimental organs must, as they grow, be as excretions 

 serving a definite purpose in the economy, by removing their appropriate mate- 

 rials from the blood,' thus leaving it fitter for the nutrition of other parts, or 

 adjusting the balance which might otherwise be disturbed by the formation of 

 some other part. Thus they minister to the self-interest of the individual ; 

 while, as if for the sake of wonder, beauty, and perfect order, they are con- 

 formed with the great law of unity of organic types, and concur with the uni- 

 versal plan observed in the construction of organic beings." 



203. But further, it has been already pointed out ( 120) that the presence 

 of a certain substance in the Blood, appears to determine the formation of the 

 tissue of which that substance is the appropriate pabulum. And thus, as the 

 abstraction of the material required for each part leaves the blood in a state 

 fitted for the nutrition of other parts, it seems to follow, as Mr. Paget has 

 further remarked (Op. cit., Lect. II.), that such a mutual dependence exists 

 amongst the several parts and organs of the body, as causes the evolution of 

 one to supply the conditions requisite for the production of another ; and hence, 

 that the order in which the several organs of the body appear in the course of 

 development, while it is conformable to the law of imitation of the parent, and 

 to the law of progressive ascent towards the higher grade of being, is yet the 

 immediate result of changes effected in the condition of the blood by the ante- 

 cedent operations. And this view is confirmed by many circumstances which 

 indicate, that certain organs really do stand in such a complemental relation to 

 one another as it implies ] a large class of facts of this order being supplied by 

 the history of the evolution of the generative apparatus, and by that of the 

 concurrent changes in other organs (especially the tegumentary) which are 

 found to be dependent upon it, although there is no direct functional relation 

 between them. Thus, the growth of the beard in man at the period of puberty, 

 is but a type of a much more important change which takes place in many 

 animals with every recurrence of the period of generative activity. This is 

 most obvious in birds, whose plumage at the commencement of the breeding 

 season, becomes (especially in the male) more highly colored, besides being 

 augmented by the growth of new feathers ; but when the sexual organs pass 

 into their state of periodic atrophy, the plumage at once begins to assume a 

 paler and more sombre hue, and many of the feathers are usually cast, their 

 nutrition being no longer kept up. It is a matter of common observation, that 

 the deficiency of hair on the face (where this is not, as among the Asiatics, a 

 character of race) is usually concurrent with a low amount of generative power 

 in the male, and may be considered as indicative of it ; whilst, on the other 

 hand, the presence of hair on the upper lip and chin of the female is indicative 

 of a tendency in the general organization and mental character towards the 

 attributes of the male, and of a deficiency in those which are typical of the 

 female. If, moreover, the development of the male organs be prevented, the 

 evolution of the beard does not take place ; whilst the cessation or the absence 

 of activity in the female organs is often attended by a strong growth of hair on 

 the face, as well as by other changes that may be attributed to the presence of 

 some special nutritive material in the blood, for which there is no longer any 

 other demand. This, again, shows itself yet more strongly in Birds ; among 



