166 LECTUEE VI. 



by facts the fallacy of his assertions in the fiist part ? Is it not 

 still more remarkable that Wagner, who studies this treatise, 

 makes extracts and long comments on it, adheres to the first 

 part without reading the second, despite that the underlined 

 passages are also rendered prominent in the original ? And is 

 it not most remarkable that M. Gratiolet, in the year 1860, 

 that is to say ten years after he had submitted his memoir to 

 the Academy, has so entirely forgotten his own results, that he 

 straightway lays down the maxim, that the superficiality of the 

 second transition convolution is " an absolute peculiar cha- 

 racter of man ? " 



But Gratiolet tells us further, "In the adult state the ar- 

 rangement of the cerebral convolutions is in the two groups 

 (man and ape) the same, and in this respect there is no suffi- 

 cient ground for separating man from the animal. But in 

 the ape the convolutions of the spheno-temporal lobe appear 

 (during the development of the embryo in utero) first, and 

 those of the frontal lobe last ; whilst in man the frontal lobe 

 convolutions appear first, and the spheno-temporal convolutions 

 last. Here, therefore, the same series of developments are 

 . from alpha to omega, and there from omega to alpha. From 

 these facts it necessarily results : that no arrest of develop- 

 ment can render the human brain more resembling that of the 

 ape than it already is. This result is perfectly confirmed by 

 the brains of the microcephali." 



Let us examine these alleged facts. The first relates to the 

 history of the development of man and ape. Is this difierence 

 so absolutely great ? It certainly only depends on the circum- 

 stance that in man the frontal lobe is more developed, that the 

 formative action is greater in that region. On this point 

 Wagner justly remarks, " However much we may adopt Gra- 

 tiolet^s asserted development difierences, there stiU obtains 

 a decided similarity (analogy and homology) in the stages of 

 cerebral development in man and the stages of development in 

 the lowest monkeys up to the highest anthropoid apes. It is 

 true that the frontal lobes in man have already in the first 

 stages a certain peculiarity, specially in the early formation of 

 the sulci. But there is a decided i-esemblance between the 



