THE JOURNAL 



OF 



THE LINNEAN SOCIETY, 



On Cerebral Homologies in Vertebrates aud I avert 3b rates. 

 By Professor Owen, C.B., F.R.S., F.L.S., &c. 



[Eead November 16, 1882.] 



[n a study of tbe homologies of the Divisions of the Vertebrate 

 brain with Nerve-centres in Invertebrates, the subjects of com- 

 parison should be the best-developed anterior and special-sense 

 masses in the latter and the least-developed ones in the former 

 subkingdom. 



In many Fishes — Lepidosteus, Anguilla, e. g.*, the neural 

 masses in direct relation to nerves of special sense are as large as, 

 or larger than, those not so related bearing the names of " cere- 

 brum" and " cerebellum," these being the homologues of those 

 centres which receive, in higher Vertebrates, such vast accessions 

 of grey and white neurine as to represent, or seemingly compose, 

 the whole organ known as the " brain " in man and most 

 mammals. 



The chief accumulation rises and expands from the parial 

 nerve-tracts or " crura " between those portions of the tracts 

 which, in front of the cerebral hemispheres, develop the masses 

 or ganglia related to the sense of " smell " and those behind the 

 hemispheres, related to the sense of " sight." JSText in retral 

 succession are enlargements related to the sense of " taste " and 

 * ' Anatomy of Vertebrates,' 8vo, vol. i. (1866) p. 275, figs. 174, 175. 



LINN. JOUEN. — ZOOLOGY, VOL. XVII. 1 



