298 MEMORIES OF MY LIFE 



delicate operations, my own part was confined to 

 inserting cannulse and the like. At first Dr. Murie 

 did all the dexterous and difficult work. He had 

 been a traveller in company with Consul Petherick, 

 far up the White Nile, and was then Prosector at 

 the Zoological Gardens. I called on him to discuss 

 the matter. A dead cobra was lying on his table, 

 and on my remarking that I had never properly seen 

 a poison fang, he coolly opened the creature's mouth, 

 pressed firmly at exactly the right spot, and out started 

 that most delicate and wicked-looking thing, with a 

 drop of venom exuding from it, just in front of his 

 nail. I thought that a man who was so confident of 

 his anatomical knowledge and of his nerve as to dare 

 such an act, must be an especially suitable person to 

 conduct my experiments, and was fortunate enough 

 to secure his co-operation. 



I continued the experiments for another generation 

 of rabbits beyond those described in the Proc. Royal 

 Society, with equally negative results. Mr. Romanes 

 subsequently repeated the experiments with my in- 

 struments, and they corroborated my own. So this 

 point seems settled. 



The laws of Heredity are concerned only with 

 deviations from the Median, which have to be 

 translated from whatever they were measured by, 

 whether in feet, pounds weight, intervals of time, or 

 any other absolute standard, into what might be 

 called "Statistical Units." Their office is to make 

 the variabilities of totally different classes, such as 

 horses, men, mice, plants, proficiency in classics, etc. 

 etc., comparable on equal terms. The statistical unit 



