1871.] Mr. F. Galton's Experiments in Pangenesis. 



399 



A comparison of the numerical results from these two formula shows 

 that no sensible difference is made if (within practicable limits) few and large, 

 or many and small, injections are made, the total quantity injected being 

 the same. 



In cross-circulation the general formula is this : — If V be the volume 

 of blood in the other rabbit, after w of alien blood has passed through 

 either canula, the quantity of blood a remaining in the Silver-grey exceeds* 



r~ f jv+V'e-(r+f) w j. This becomes ^|l+e"T j whenV=V; 



also, when V is infinite, it gives the formula already mentioned for injec- 

 tion by a continuous flow of purely alien blood. 



Table I. 



(Contents of circulation of Silver-grey Rabbit = 100.) 



Quantity 

 of 

 blood 

 infused. 



Maximum percentage of original blood remaining 

 after 



Period, in mi- 

 nutes, during 

 which the 

 continuous 

 flow through 

 each carotid 

 has lasted. 



Successive injections 

 of purely alien blood, 

 each =1™.. 



1 2 



Continu- 

 ous flow 

 of purely 

 alien 

 blood. 



Cross-circulation. 



Eabbits 

 of equal 

 size. 



Blood- mate 

 T77 larger 

 than the 



Silver-grey. 



25 

 50 

 75 

 100 

 125 

 150 

 175 

 200 



Number of 

 injections. 



6 



9 

 12 

 15 

 18 

 21 

 24 



77 



59 

 46 

 35 

 27 

 21 

 16 

 12 



78 

 61 

 47 

 37 

 29 

 22 

 17 

 14 



80 

 68 

 61 

 56 

 54 

 52 

 51 

 51 



80 

 68 

 60 

 55 

 52 

 51 

 50 

 49 



2i 

 5 



7* 

 10 

 12* 

 15 



m 



20 



300 



36 



4 



5 



50 



48 



30 



400 



48 



1 



2 



50 



48 



40 



infinite 



infinite 











50 



48 



infinite. 



I now give a list (Table II.) of the rabbits to which, or to whose blood, 

 mates, I shall have to refer. Every necessary particular will be found in 

 the Table : — the weight of the rabbits ; the estimated weight of blood in 

 their veins ; the operations performed on them, whether u, w, or x ; the 

 particulars of those several operations ; the estimated percentage of alien 

 blood that was substituted for their natural blood ; and lastly, the colour, 

 size, and breed of their blood-mates. 



* I am indebted to Mr. George Darwin for this formula. 



2 h 2 



