226 'A Cage for Metabolism Experiments on Goals [Dec. 



respects, it has served its purpose. It is to be hoped that other 

 investigators will try the goat in studies of their metabolism Prob- 

 lems. We may then expect developments both in the construction 

 of the cage, and in the manner of conducting experiments with 

 goats, leading to the perfection of technic which we now have in 

 experiments on dog metabolism. Such a piece of apparatus as a 

 metabolism cage is necessarily the product of evolution along lines 

 suggested by the investigator's experience. To Professor Gies we 

 are greatly indebted for the perfection of technic in experimenta- 

 tion on dog metabolism. He has given us the first published de- 

 tailed description of a dog cage suitable for accurate quantitative 

 work. His improved device, as described in 1905, in the American 

 Journal of Physiology, Volume XIV, page 403, was the Suggestion 

 from which this goat cage resulted. 



EXPLANATION OF PLATE V. 

 (See description on pages 223-225.) 



