122 Mr. G. P. Mudge. Intravascular Coagulation [Oct. 16, 



(unpigmented) instead of pigmented eyes and in never becoming periodically 

 wholly pigmented. It cannot, therefore, be used as corroborative evidence of 

 Pickering's conclusion with respect to the Norway hare. 



5. That failures to coagulate, when they occur, are due to inherent 

 qualities of the individuals and not to weakening in the activity of the 

 solutions used. 



6. Albinoes require a larger mean dose per kilogramme of body weight of 

 injected nucleo-proteid to cause death by intravascular coagulation than do 

 pigmented animals, the relative resisting powers of the pigmented and 

 albino individuals being as 1 to 1*5 respectively. 



7. Both albino and pigmented individuals are more resistant to nucleo- 

 proteids, obtained from individuals of their own race, than they are to those 

 obtained from the alternative source. 



8. The activity of a solution of nucleo-proteid, prepared from spermatic 

 glands, decreases (but not quite uniformly) as the maturity (weight) of the 

 gland increases. 



9. Solutions of nucleo-proteids, prepared from heavier (maturer) spermatic 

 glands, undergo a progressive loss of activity with increasing period of 

 keeping, i.e., from 1 to 20 days. But solutions derived from lighter 

 (immature) glands undergo a fluctuating variation in activity, falling off on 

 the second day after preparation and rising again on the fifth to seventh, 

 and thence exhibiting a progressive fall. 



NATUKE OF SOLUTIONS USED. 



W.G. = weight of gland ; D. = dissolved in 1-per-cent. solution of anhydrous Na 2 C0 3 . 

 The amount of solution used in each case is indicated in cubic centimetres. Unless other- 

 wise stated, all the solutions were prepared by pressing the glands through finely meshed 

 iron wire gauze into 1-per-cent. solution of Na 2 C0 3 . 



Sol. A. — (1) Thymus glands from four albino rats, 6 weeks old, descended from albino 

 parents. (2) Testes from albino rat of unknown parentage. (3) Thymus from 

 albino rat, 8 weeks old, from black and white parents. W.G. = 4*2 grammes, 

 D. in 65 c.c. = 1 gramme in 15*5 c.c. 



Sol. B. — Thymus gland of a black and white calf. Portion of organ minced and ground 

 in a mortar with an equal volume of sodium chloride. Separated the nucleo- 

 proteid by addition of distilled water, and collected into 1-per-cent. solution of 

 Na 2 C0 3 . Strength of solution was not ascertained, but was probably nearly 

 saturated. 



Sol. C. — Testes from albino rabbit. W.G. = 6 grammes, D. in 100 c.c. = 1 gramme in 

 15*5 c.c. 



g i t ]). — Thymus glands from four young pigmented rabbits, with much unpigmented 

 coat. Glands crushed in distilled water, macerated for 36 hours, and the nucleo- 

 proteid then precipitated by 0'2-per-cent. acetic acid. Dissolved in 70 c.c. of 

 1-per-cent. solution of Na 2 C0 3 . 



