THE BRADSHAW LKCTUEE. 29 



of cross-breeding : yet when, in the human race 

 a negro unites with a white, the result is a half- 

 caste or mulatto. So also when a European 

 unites with an Indian, the result is a Eurasian. 

 Mulattoes united in marriage should, according to 

 Mendelian law, segregate out into pure blacks, 

 pure whites, and intermediates, but they do not ; 

 they continue to produce mulattoes, and Eurasians 

 continue to produce Eurasians. 



The Galtonian or biometrical school rely upon 

 a statistical method of investigation. By collec- 

 ting a large number of measurements or observa- 

 tions they gain material from which to deduce 

 ]aws of heredity. Gralton began by taking height, 

 and maintained that what was true of one quality 

 would probably prove true of all. His statement 

 that half the heritage of a child is derived from 

 his two parents, one quarter from the four grand- 

 parents, and one sixteenth from the great-grand- 

 parents, is so well known that I only mention it 

 in passing. Professor Karl Pearson, repeating 

 these observations, did not find the progression so 

 regular, but the main results were not very dis- 

 similar. Much has been done in this school since 

 those early days, and the probabilities of many 

 qualities have been worked out. 



It will be gathered from my critical remarks 



