HOMOLOGY OF HUMAN AND FELINE FISSURES. 503 



tologically as well as physiologically analogous," although in a previous paper (1, 24) he 

 had declared that " anatomically, the crucial and Rolandic are not capable of comparison ; " 

 Lussana and Lemoigne (A, Fig. 75) make the cruciata equivalent to the calloso-marginatis 

 of man, while Duval and Keller (Huguenin, A, 57, note) consider it as " 1'analogue du sil- 

 lon perpendiculaire externe ou sillon occipital de rhomrne ; " Broca (i, 407) is sure that 

 the cruciata is not the representative of the centralis, and its existence with the Primates 

 is denied altogether by Hitzig (A, 430) and Meynert (1, 659, note). 



After having followed up all the clues at our disposal, and spent upon this 'single mat- 

 ter more time than we supposed would be required for the elucidation of the gross anat- 

 omy of the entire brain, we are forced to admit our inability to satisfy ourselves completely 

 with respect to the homology of the carnivoral fissures with those of man, excepting of 

 course the hypocampal and callosal, which have never presented any difficulty on account 

 of their relation to structural features ; as to the existence of a "lambdoidal " or "occipi- 

 to-parietal " fissure in the cat, see 1834 (20). 



So long, indeed, as any doubt exists with regard to the correspondence of the fissures 

 of the cat, seal and raccoon, and of man, Macacus and Lemur, it is hardly to be expected 

 that the homology between the members of the two groups should be altogether clear. 



1371. The following lines of inquiry seem likely to be most productive of results : 



(1) Numerous and careful preparations and drawings should be made of the brains of 

 all Carnivora and monkeys, especially of the young. The same should be done for pecu- 

 liar foetal and adult human brains. 



(2) Between the ordinary Carnivora and the monkeys are two groups whose brains 

 should be studied with especial care : the seals have a rudimentary postcornu and occipital 

 lobe, and these parts are said to be well developed in the Lemurs, which have affinities 

 with both the Carnivora and the Primates. 



Respecting the brains of the lower Vertebrates, see Appendix, 1455. 



