76 Drs. F. A. Bainbridge and A. P. Beddard. [Nov. 20, 



Two or three weeks later the opposite kidney was removed under ether 

 anaesthesia through an abdominal incision. 



The animals were kept in cages whose floor consisted of a wire netting ; the 

 cages stood upon a zinc plate, sloping towards the centre, which was 

 perforated by a small hole. The urine ran down the zinc sheet through the 

 hole into a basin containing a little chloroform. The urine and faeces were 

 collected every 24 hours, and very great care was taken to keep the urine 

 free from food or faeces. 



The cats were kept at a fairly even, moderate temperature, and were 

 allowed some exercise daily in the laboratory. 



The food was measured daily, and any food left over was also measured. 

 Their diet consisted of minced meat, milk and water ; the amount of the 

 latter, of course, was not restricted. 



The total nitrogen in the meat and milk was estimated by Kjeldahl's 

 method. A considerable amount of meat was minced, and mixed into a 

 uniform mass ; a sample of this was analysed, and the rest kept in an ice 

 chest ; the cats received a definite quantity each day. 



The urine was analysed daily ; the faeces were collected for several days, 

 and the total nitrogen present estimated. The total nitrogen of the urine and 

 faeces was estimated by Kjeldahl's method, the urea by a modification of 

 Folin's method, the ammonia by Schaffer's method, and the creatinin by the 

 colorimetric method of Folin. All the analyses were made in duplicate. 



Results. 



The effects of removing portions of the kidneys may be grouped as 

 follows : — Firstly, the general conditions of the animals including changes in 

 body weight ; secondly, the nitrogenous metabolism ; thirdly, alterations in 

 the amount and concentration of the urine. 



I. The Condition of the Animals. — After the first operation, the cats 

 usually drank a little milk on the same day, but for several days their 

 appetite was poor, and they lost weight. Eventually they ate very well, 

 and appeared to be more hungry than normal cats. For a day or two the 

 urine contained blood, and for another two or three days albumen was 

 present. 



Three cats survived the second operation for some time ; they rapidly 

 recovered from the anaesthesia, and showed very little shock. 



Two of the three cats ate very little after the second operation, and 

 refused food altogether during the last few T days of life ; the third cat ate well 

 for 10 days, when its appetite also failed. 



Vomiting and diarrhoea were observed in all the cats, and they seemed 



