176 Messrs. Boyce and Warrington. Anatomy and 



green glow, on disconnecting the induction coil and magnetising the 

 electrodes, a flash of white light was observed within the tube, and 

 irregular green splashes momentarily made their appearance upon the 

 glass. 



In conclusion, I desire to offer my thanks to Dr. Silvanus P. Thomp- 

 son, F.R.S., for kindly permitting me to use the Tesla apparatus at 

 his laboratory, and for the interest he has taken in the progress of these 

 experiments. 



" Observations on the Anatomy, Physiology, and Degenerations of 

 the Nervous System of the Bird." By II. BOYCE and W. B. 

 WARKINGTOX. Communicated by Professor SHERRIXGTON, 

 F.K.S. Keceivecl December 7, Head December 15, 1898. 



(Abstract.) 



In this research the modern methods of investigating the course of 

 tracts and their degeneration in the central nervous system have been 

 used. The previous literature of the subject is scanty. Bumm first 

 gave an account of the various tracts in the brain, and the histological 

 side has been and is still being worked out by Brandis. 



Valuable information is given by Edinger in his * Vorlesungen,' and 

 quite recently the March! method has been used and the results 

 obtained described by Wiener and Miinzer, Wallenberg and Fried- 

 lander. 



The anatomy has been studied by sections made in the three planes 

 and stained by the Weigert and Nissl methods, and by observing the 

 course of the degenerated fibres following various lesions, staining by 

 Marchi's fluid. 



In the brain of the Bird the cortex of higher animals is represented 

 by a thin pallial sheet of grey matter, forming the mesial and dorsal 

 boundary of the narrow ventricle, and gradually losing itself on the 

 lateral aspect of the hemisphere. Its substance is composed of oval, 

 rather large cells, grouped into clusters, and it contains the fibres of an 

 important tract, called by Edinger the Tr. septomesencephalicus, and 

 by us alluded to as the pallial tract. The hemispheres themselves cor- 

 respond to basal ganglia ; posteriorly they expand laterally into the 

 large occipital lobes. Their substance contains cells resembling those 

 found in the pallium, and which cannot be differentiated distinctly into 

 definite regions. 



The hemispheres are connected with the thalamus by a constriction 

 of their substance, forming an isthmus on either side, from which the 

 thalamus in transverse section is seen suspended as a triangular shaped 

 body. 



