493 



NOTE ON CEREBRAL LOCALIZATION IN THE 

 BANDICOOT (PERAMELES). 



By H. Gr. Chapman, M. D., B.S., Demonstrator op Physiology 

 in the University of Sydney. 



(From, the Physiological Laboratory of the University of Sydney.) 



Historical. — The positions of the cortical motor centres in the 

 brains of marsupials have been described in the Opossum 

 (Didelphys virginiana) by Ziehen,* and by R. Cunningham;! 

 and in the Native Cat (Dasyurus viverrinus) by Flashman.t 



Scope. — In this investigation the motor areas have been observed 

 in Perameles nasuta and P. obesida. The centres described have 

 been found regularly in each animal and on both sides of the 

 brain. Other movements have been seen in single individuals, 

 but as these latter movements have not been found constantly 

 they are not mentioned here but will be the object of further 

 inquiry. Experiments by ablation of the cortical centres with 

 observation of the subsequent behaviour of the animal and 

 consequent degeneration in the brain have not as yet been com- 

 pleted and will be reserved for future communication. 



Methods. — After preliminary administration of ether, trache- 

 otomy was performed, a tube was inserted into the trachea, and 

 anaesthesia was maintained by causing the animal to breathe 

 through a Woulffs bottle containing ether. The skin was 

 incised to expose the calvarium, and the bone chipped away after 

 an aperture had been made with a small trephine. Almost the 



* Centralb. f. Physiol., 1897, Bd.xi. s.457. 

 t Journ. of Physiol., 1897-1898, xxii. p.264. 

 X Reports from Pathological Laboratory of the Lunacy Department, New 

 South Wales, Vol. i., Pt. ii., 1906. 



