444 PROF. \V. X. V. WOODLAND O.N LIGATURING TIIIC 



and the womul cleansed with weak carbolic acid, carbolic ointment 

 being I'ubbed on the sui'fa.ce. While tlie wound was healing, I 

 covered it with a pad of cotton avooI, protected witli a waterproof 

 sheet, tlie four comers of which were drawn out and tied anteriorly 

 above the scapulaj and under the animal's throat, and posteriorly 

 over its back. The animals were given an occasional bath in 

 shallow distilled water (the skin having previously l)een well 

 cleaned), but were normally kept dry, the pad protecting the 

 wound from urine and fgecal matter in the basin. 



Out of 11 toads operated on as above described (save that I 

 only ligatured the anterior abdominal vein in one place) in 1915, 

 one lived for ten days, one for fourteen days, one a day short of 

 eight weeks, and two others were killed after eight weeks and 

 eleven weeks respectively. I shall only record my examination 

 of the three long-period sui'vivors, all of which were opei'ated on 

 on October 1st, 1915, and the wounds healed by October 12th. 

 A day or so later they were all active and feeding well. 



One, as already stated, died on November 26tli, one day short of eight weeks 

 after the operation. It was very thin, and had been ill during the previous vveelc. 

 It weighed at death (after subtracting weight of food in gut) 21'o gms. The heart 

 was normal in size (heart ratio =229'0*) ; the liver a trifle large (liver ratio=2r5*). 

 The liver was verj' diseased, being full of small cysts; the spleen was much enlarged 

 and also full of cysts, and the fat-bodies very minute. Sex not recorded. The 

 anterior abdominal vein was found to be well ligatured and was quite empty ; on the 

 other hand, the renal afferent veins and post-caval were very large, and the two 

 kidneys (quite healthy) were gorged with venous blood and therefore rather dark in 

 colour. It is important to note that a neiv anterior ahdominal ■veinhad not heen 

 formed. The kidneys, after as usual being slightly squeezed and all attaclicil vessels 

 removed, weighed together 0"230 gm., and tvere therefore apparenth/ enornnmslii 

 enlarged (kidney ratio=93"5*, body-weight taken at death). 



The toad (a male) which I killed on November 28th — eight weeks and one day 

 after the operation — was perfectly healthy, being active and feeding well,an<l all the 

 internal organs in perfect condition. In this toad I found to my surprise that a new 

 vein hadheen formed posterior to the ligature and entering the liver, also tiro or 

 three small new veins coming from the muscles of the anterior ventral hody-wall and 

 opening into the principal neio vein (text-fig. 1, H)t. The body- weight (after weight 

 of food in gut subtracted) was 21'9 gms. Tlie heart ratio was 199"3*; the liver 

 (weighing exactly 1"0 gm.) ratio = 23'9*; the kidney ratio=l(>I'8 *. The kidneys, 

 therefore, were about normal in size. 



The remaining toad (a male) 1 killed on December 18th — eleven weeks after the 

 operation — and this also was in perfect health inside and out. In this toad also a 

 neiv vein had been formed to allow the ligatured anterior abdominal to becom(> 

 functional. The body-weight was SO'O gms. The heart ratio=229'0*; the liver 

 ratio = 19'6*; the kidney ratio=157'9*. The kidneys, therefore, were about normal 

 in size. 



* The normal (average) ratio — s»r^ ' r ■ foi' the heart (all vessels cut off and 



^ ° Wt. ot viscus ^ 



all blood washed out and dried) in these toads is 216'8 (determined in 29 toads) ; the 



normal ratio for the liver (squeezed and dried) was 28"4 (18 toads) ; the normal ratio 



for the kidneys (wt. of, both kidneys, attached ureters and vessels being removed) 



was 237'6 (82 toads). I must add, however, that in two other lots of toads the 



average kidney ratios .were 155'2 (10 toads) and 159"3 (6 toads). The kidney ratio 



(also the heart and liver ratios) shows great variations, not connected with the time 



of year or with sex. 



f Compare the " rapid formation of a collateral circulation so that the blood could 



get round the ligature to the liver " (Starling, ' Principles of Human Physiology,' 



1912, p. 858) when in a mammal the portal vein was ligatured off from the liver and 



made to open into the posterior vena cava. In this case, however, the liver is 



deprived of blood from the gut and not merely of an additional supply of ordinary 



venous blood, as in the toads with ligatured renal afferent veins. 



