G. NATURAL HISTORY AND ZOOLOGY. 291 



Professor Ferrier's researches in reference to the functions of 

 the cerebrum, arrives at the following conclusions : 



1. That it is possible by exciting certain points of the 

 cortical layer of the cerebrum to obtain contractions in every 

 limb. 



2. That, as a rule, the fore-limb of the opposite side is that 

 affected. 



3. That the electric current must be propagated to the 

 base of the cerebrum to excite either the nerves which arise 

 from it or the base itself or the pous varolii. 



4. That if the dura mater be electrically excited, contrac- 

 tions are observed in the fore leg, and generally in that of 

 the opposite side. 



5. The fact that the galvanoscopic frog is thrown into a 

 state of contraction when its nerve touched some point of 

 the cerebral mass far from the point excited, confirms the 

 view that the electric current is propagated. 



6. Contrary to the effects obtained by Ferrier, M. Dupuy 

 has never been able to obtain any effects upon the tongue, 

 either of projection or of retraction. 



7. The whole cortical layer of the cerebrum is probably a 

 centre of reflection for a certain kind of sensibility capable 

 of exerting a reflex action on motor or sensory nerves ; but 

 that its preservation is not indispensable for the manifesta- 

 tion of voluntary and even intelligent action. 



8. In the animals on which M. Dupuy has experimented 

 contractions of the opposite limbs can still be produced, even 

 after the ablation of the optic thalami and corpora striata 

 of the opposite side to that on which the irritation is applied. 

 13 A, February 14, 1874, 178. 



COMPOSITION OF THE BODY FLUIDS OF FISH AND INVERTE- 

 BRATES. 



Messrs. Rabuteau and Papillon have been prosecuting some 

 inquiries into the various liquids in the cavities of fish, crus- 

 taceans, and cephalopods, and state that the peritoneal fluid 

 found in rays is neutral, or slightly acid, and contains a small 

 quantity of an albuminoid material, which forms a rather 

 thick layer on the surface when the liquid is evaporated. 

 When kept, it gives off an ammoniacal odor resembling 

 methylamine. The gastric juice of the ray is rather acid, 



