AXTEllIOR ABDOMINAL VEIX IN THE INDIAN TOAD. 



445 



In 1916 I was unfortunate in this experiment, possibly owing 

 to my predilection for giviui^ tlie animals a bath every morning, 

 but probably also owing to the fact that in each operation I 

 ligatured the anterior abdominal vein in two places and cut out 

 a portion about half a centimetre in length in between. Out of 

 23 toads operated on only five survived for more than eleven 

 days. That this was due largely to the mode of operation and 

 not solely to the ligature of the anterior abdominal vein is shown 



Text-fio^ure 1. 



NV 



-LIG 



A 



A 



B 



A. Suiall re^'euerated anterior uljdoiuiiiul win in a toad wliicli w as killed four weeks 



after tlie operation. LIG, positions of tlie two ligatures, tlie intervening- 

 l)ortiou having been cut out in the operation. NV, new vein formed. 



B. Large regenerated anterior abdominal vein m a toad killed eight weeks and one 



day after the operation, which merel.y consisted of the vein being ligatured 

 in one position. GB, gall-bladder ; other letters as in A. 



I cannot guarantee the absolute fidelity of these figures, since the}^ have 

 been copied from rather rough sketches made wben 1 dissected the toads. 



by the fact that out of ten control toads in which an identical 

 operation was performed, save that the exposed anterior abdominal 

 vein was not ligatured, nine of them did not survive for longer 

 than eleven days, and only one for six weeks and two da3^s. 



Of the live survivors ot the actual operation in 1916, one which survived eleven 

 days had a kidney ratio (in all these ratios, unlike those of 1915, the weight of the 

 body is that taken at date of operation) of 119"7 ; another which survived twelve 

 days had a similar kidney ratio of 134'2 ; another survivor of two weeks and one da^' 

 had a kidney ratio of 95'8. Only one toad completely survived the operation, and 

 this was a female which I killed four wei-ks after the operation. The animal was 

 then in perfect health inside and out, and in this case I found that a new vein had been 

 fji'med to enable the anterior abdominal vein to conthiue to function (text-fig. 1, A). 

 The animal weighed 23"4 gms. on the date of operation (July 22nd), but when killed 



