TO THE LOWER ANIMALS 293 



A succinct History of the Controversy respecting the 

 Cerebral Structure of Man and the Apes 



UP to the year 1857 all anatomists of authority, who had occupied 

 themselves with the cerebral structure of the Apes Cuvier, Tiede- 

 maim, Sandifort, Vrolik, Isidore G. St. Hilaire, Schroeder van der 

 Kolk, Gratiolet were agreed that the brain of the Apes possesses 



a POSTERIOR LOBE. 



Tiedemann, in 1825, figured and acknowledged in the text of 

 his Icones the existence of the POSTERIOR CORNU of the lateral 

 ventricle in the Apes, not only under the title of ' Scrobiculus parvus 

 loco cornu posterioris ' a fact which has been paraded but as 

 ' cornu posterius ' (/cones, p. 54), a circumstance which has been, 

 as sedulously, kept in the background. 



Cuvier (Lecons, T. iii. p. 103) says, " the anterior or lateral 

 ventricles possess a digital cavity [posterior cornu] only in Man 

 and the Apes ... Its presence depends on that of the posterior 

 lobes." 



Schroeder van der Kolk and Vrolik, and Gratiolet, had also 

 figured and described the posterior cornu in various Apes. As 

 to the HIPPOCAMPUS MINOR Tiedemann had erroneously asserted 

 its absence in the Apes ; but Schroeder van der Kolk and Vrolik 

 had pointed out the existence of what they considered a rudimentary 

 one in the Chimpanzee, and Gratiolet had expressly affirmed its 

 existence in these animals. Such was the state of our information 

 on these subjects in the year 1856. 



In the year 1857, however, Professor Owen, either in ignorance 

 of these well-known facts or else unjustifiably suppressing them, 

 submitted to the Linnsean Society a paper " On the Characters, 

 Principles of Division, and Primary Groups of the Class Mammalia," 

 which was printed in the Society's Journal, and contains the following 

 passage : " In Man, the brain presents an ascensive step in develop- 

 ment, higher and more strongly marked than that by which the 

 preceding sub-class was distinguished from the one below it. Not 

 only do the cerebral hemispheres overlap the olfactory lobes and 

 cerebellum, but they extend in advance of the one and further back 

 than the other. The posterior development is so marked, that 

 anatomists have assigned to that part the character of a third 

 lobe ; it is peculiar to the genus Homo, and equally peculiar is the 

 posterior horn of the lateral ventricle and the ' hippocampus minor,' 

 which characterise the hind lobe of each hemisphere." Journal of 

 the Proceedings of the Linneean Society, Vol. ii. p. 19. 



As the essay in which this passage stands had no less ambitious 

 an aim than the remodelling of the classification of the Mammalia, 

 its author might be supposed to have written under a sense of 

 peculiar responsibility, and to have tested, with especial care, the 

 statements he ventured to promulgate. And even if this be expect- 



