24 



SCIENCE 



[N. S. Vol. XXXIX. No. 992 



page proof which could have been given in a 

 few lines. 



5. If, in the three years intervening between 

 my review and his attack on it, Professor 

 Skinner had given less time to the counting 

 of footnotes and more time to the compre- 

 hension of the passages quoted from my re- 

 view and to the unquoted context of those 

 passages, he would possibly have saved him- 

 self from " careless and inaccurate state- 

 ments," instead of attributing that term so 

 freely to my review. 



6. Professor Skinner makes on page 150 

 the remarkable statement : 



Furthermore, the author has put in a very clear 

 light the historical sequence of the ideas which 

 led to the development of the theory. 



On the contrary, the author made no such 

 pedagogical blunder. He wisely did not at- 

 tempt to give any idea of Kummer's ideal 

 numbers, the operations on which are so deli- 

 cate that one must use the utmost circum- 

 spection (as remarked by Dedekind in his 

 important historical papers in Darboux's 

 Bulletin). Nor did the author present the 

 second stage (Dedekind's viewpoints) in the 

 historical development of the theory. For 

 most obvious reasons the author refrained 

 from presenting " the historical sequence of 

 the ideas," and confined himself to the simpli- 

 fied present-day exposition of the theory, as 

 far as he went. 



L. E. Dickson 



A REJOINDER TO DR. DAVENPORT 



The task of the critic is always a disagree- 

 able one, and it is only the conviction that the 

 fate of eugenics as a science depends on the 

 repudiation of much of the recent work of 

 the Eugenics Record Office which impels me to 

 reply to Dr. Davenport's letter in Science of 

 November 28. I shall confine myself to the 

 three points he raises regarding the paper on 

 heredity in epilepsy although these points are 

 not in the least representative of my criticism 

 of that paper. Indeed, I dealt with not one, 

 but a whole series of publications in which Dr. 

 Davenport is concerned. 



(a) Dr. Davenport states that 



First, Dr. Heron seems to assume that when- 

 ever a symbol in a pedigree chart is not accom- 

 panied on the chart by some special description it 

 stands for a person about whom nothing is 

 known. He calls attention to numerous cases 

 where, notwithstanding, the corresponding indi- 

 vidual is described in the text. The assumption is 

 a gross error. The chart shows mainly the inter- 

 relationship of individuals, and indicates only 

 certain traits. 



Bulletin No. 2 of the Eugenics Eeeord 

 Office'^ is entitled " The Study of Human He- 

 redity " and the opening sentence reads : 



The following methods are in use at the Eugen- 

 ics Record Office. . . . 



The " plan of charting " adopted is de- 

 scribed in section 2 and it is there stated that 

 while the letters E, F, I, N, etc., placed in or 

 around the square or circle which stand for 

 male or female, indicate that the individual 

 in question is epileptic, feebleminded, insane 

 or normal, etc., " when no letter accompanies 

 the individual symbol it means that no defi- 

 nite data had been secured at the time the 

 chart was made" (page 4). Further, Plate V. 

 on page 16 is entitled " Key to Heredity 

 Chart " and there examples of the symbols 

 used are given. The first two are the square 

 and circle without any accompanying letters 

 and the description given is " No data." 

 Again, in his tables Dr. Davenport uses a 

 symbol X which he defines as " Unknown " 

 (I pointed out that more than half the indi- 

 viduals entered in the tables were described by 

 Dr. Davenport himself as "unknown"). Now 

 in the great majority of cases the square or 

 circle without any accompanying letter cor- 

 responds to an individual marked " unknown " 

 in the tables, but I pointed out several cases 

 where mistakes had been made. To take the 

 first example I gave in my paper. Fig. 10, case 

 469, the chart shows two sisters one of whom 

 is marked epileptic while the symbol for the 

 other is left blank to indicate that " no defi- 

 nite data had been secured at the time the 

 chart was made " or that there were " no 



1 It was reprinted in Bulletin No. 7 of the 

 Eugenics Eeeord Office, September, 1912. 



