66o Organic Physics. [August, 



polar corpuscle. If so, the germ thence arising would have a 

 double, or perhaps a triple polarity in some of its molecules. And 

 this duplication will be more complete as the gland producing it 

 is a more central one. It may vary from the production of a 

 slight duplication of tissue to that of a combination of two fully 

 generalized leucocytes. If such a germ, with part or all of its 

 molecules doubly polar, combine with a germ of the opposite 

 sex and develop, the bisexual germ thus produced would be, to 

 some extent, bipolar at one sexual pole and unipolar at the other. 

 But as each pole exerts a controlling influence upon the develop- 

 ment of the other, the result might be a bipolar or a unipolar or- 

 ganism, as one or the other sexual pole was preponderant in 



If duplication of organs or of bodies has its origin in the action 

 of the glands upon the development of the leucocytes, as here 

 supposed, this must, in some cases at least, result from abnormal 

 organization of the glands. Only thus can be understood the fre- 

 quent recurrence of the same malformation out of the same 

 parents ; this extending to the extreme case of twin births, which 

 may occur more than once from the same mother. 



Having thus offered some conjectural explanations as to the 

 physiological cause of abnormal births, it remains to consider 

 their bearing upon the question of the origin of species. 



Abnormal offspring do not succumb without a struggle for life. 

 Twin monstrosities often survive to maturity. A deficiency so 

 extreme as the total lack of a brain does not cause immediate 

 death. Brainless children have survived for some time after 

 birth. Of course the chances are enormously against extreme 

 aberrations from the normal type being transmitted. But slight 

 aberrations are sometimes stubbornly transmitted, particularly if 

 they be such as do not specially affect the life chance oi the indi- 

 vidual. Thus an extra finger may be sent down through several 

 generations, and undoubtedly could, by intelligent sexual selec- 

 tion, be made a type feature. It stubbornly resists reversion 

 through the influence of union of the abnormal with a normal 

 individual. 



There is a race prejudice which operates against the transmis- 

 sion of external abnormalities, but which cannot affect that of in- 

 ternal ones. The duplication of a muscle, for instance, would not 

 appear externally, yet might give the animal possessing it some 



