1906.] in Albinoes and Pigmented Animals, etc. 119 



But an inspection of the curves in fig. 2 (upper and lower), shows that upon 

 analysis this result apparently holds true for a part only of the range of 

 gland- weight. If the conclusion were generally true, the curve for pigmented 

 animals injected by " albino " nucleo-proteid should be lower throughout its 

 range than for those injected by " pigmented " nucleo-proteid ; and the curve 

 for albino individuals injected with "pigmented" nucleo-proteid should also 

 be lower throughout its range than that for those injected by "albino" 

 nucleo-proteid. But this is not wholly the case. With the albino individuals 

 (fig. 2, upper) the two curves are relatively as they should be throughout the 

 greater part of their range, the lower one crossing the upper one towards the 

 left. But this crossing obviously may be due to the absence of any data for 

 " pigmented " testis weighing 1 gramme, and to that for " albino " testis 

 weighing 0*6 gramme. The same considerations hold for the pigmented 

 animals (fig. 2, lower) ; had data been available for " pigmented " testes of 

 1 gramme and 4*2 grammes, the " pigmented " curve may have been lowered 

 at these two points, and they would then have followed a uniform course 

 throughout their range, the " albino " line being the higher. 



(B) Variation in the Activity of Solutions of Niicleo-proteids with 



Increasing Age. 



In the experiments described in this paper, most of the injections were 

 made on the same day that the solutions of nucleo-proteid were prepared, 

 some of them two days later (so that the solution, inclusive of the day of its 

 preparation, was then three days old), and some of them five days later (the 

 solution then being six days old), and a few at still later periods. If we 

 examine the results obtained by using the same solution on different days it 

 is found that the mean dose per kilogramme of body weight required to 

 clot varies with the age of the solution. There were seven different 

 solutions, i.e., I, K, O, P, E, S, and T, each of which were used on different 

 days. Four of these, i.e., E, S, T, and K, which were derived from heavier 

 glands {cp. p. 122 and figs. 1 and 2), gave a continuous fall of strength with 

 increasing period of keeping, but three of them, i.e., I, 0, and P, which were 

 derived from lighter glands, gave different results (fig. 3). 



The E, S, and T solutions were tested on the day of preparation and on 

 the second and fifth days after, and the K solution on the day of 

 preparation and on the second day after. All these solutions fell in strength 

 with each successive period, but the S solution fell markedly on the fifth 

 day. With respect to the T solution, experiment 172 has to be eliminated, 

 owing to idiosyncrasy ; how marked it is can be seen by comparison with 

 experiment 171. 



vol. lxxix. — B. L 



