Ixiv Journal of Comparative Neurology. 



further told that most of the matter contained in this part was aheady 

 in type, though not finally corrected for the press, at the time of the 

 author's untimely death. These, as well as the other parts which were 

 left in manscript, have suffered only verbal alterations at the hand of 

 the editor. 



The work falls into the two great sections indicated in the sub-title, 

 the first chapter constituting a general introduction to the whole. As 

 this introduction has been otherwise published in a leading periodical 

 we need not stop to review it here. 



The first section on heredity, which receives the title, Characters 

 as Hereditary and Acquired, is taken up almost wholly with the specu- 

 lations of Weismann; it, however, covers very different ground from 

 the earher work, "An Examination of Weismannism." The logical 

 system which goes by the name of Weismannism is graphically de- 

 scribed as consisting of a basal postulate as to the absolute non-inherit- 

 ance of acquired characters, upon which is erected a Y-like system of 

 deductions. The stem of the Y is the deduction as to the absolute 

 continuity of germ-plasm, the limbs of the Y are constituted by deduc- 

 tions as to the architecture of the germ-plasm and deductions as to the 

 theory of organic evolution respectively. Now, in the Examination 

 Mr. Romanes assumed the postulate and then examined the deductions 

 which make up the Y ; in the present work he deals only with the 

 basal postulate. 



But here we meet a dead-lock which Mr. Romanes has taken 

 great pains to make plain both in this connection and in previous pub- 

 lications. Weismann calls for proof that acquired characters are not 

 transmitted in a state of nature. But when an apparent case of such 

 transmission is presented, he replies. How do you know that the char- 

 acters in question are not adaptive and therefore perpetuated by natural 

 selection ? But if cases of the transmission of non-adaptive characters 

 are adduced, he replies that there are no such characters. Seeing that 

 natural selection is taken to be the only possible cause of change in 

 species, it follows that all changes occurring in species must necessarily 

 be adaptive, whether or not we are able to perceive the adaptations. 

 The case, then, is very much like that of a doughty knight pitching his 

 glove into the sea, and then defying any antagonist to take it up. "Prob- 

 ably enough has now been said," Mr. Romanes adds, " to show that 

 the Neo-Darwinian assumption precludes the possibility of its own 

 disproof from any of the facts of nature (as distinguished from domes- 

 tication) — and this even supposing that the assumption be false. On 

 the other hand, of course, it equally precludes the possibility of its own 



