436 



have been made as jet. The inlieritance of the headforni has not 

 jet been investigated methodicallj. Hurst ') mentions in a list 

 of properties, which segregate according to Mendel's rules, that round- 

 headedness is dominant over iongheadedness and E. Fischer ") con- 

 cludes, from his bastard-material, that the headform is most probablj 

 hereditarj according to the rules of Mendel. Fischek gives moreover 

 quotations from the literature of non-mendelistic investigations, which 

 are in favour of the theorj that brachjcephalj is dominant over 

 dolichocephalj. 



The above-mentioned twofold signification of analjtic investigations 

 into hereditj in man has induced me to investigate the hereditj 

 of the headforni. The present first communication regards the results 

 of a thousand measurements. Mj material consists of the visitors 

 calling on the patients of the lunatic asjlum Maasoord of Rotterdam. 

 Bj numerous journejs to Rotterdam and other places, consequentlj 

 somewhat in the manner of the fieldworkers, I have measured as 

 completelj as possible all the members of those families for whom 

 this was of importance. Also a few other families have been inserted 

 into the tables. The extensive tables, on which the communication 

 rests, will be published later. All the measuremejits and calculations 

 have been executed bj myself. 



The anthropological knowledge of the headform maj likewise 

 serve as a guide for the choice of the shape of the head for 

 a Mendelean investigation. A. Rf.tzils has not given any fixed values 

 for the dolichocephalic and the brachjcephalic skull. In a letter to 

 DuvERNOY (1852) he sajs *) that with the dolichocephalic skull the 

 length as a rule surpasses the width bj i, whereas with the brachj- 

 cephalic skull this difference varies between ^ and i. These figures 

 mean for the dolichocephalic skull an index value <^ 75 and for 

 the brachjcephalic one an oscillation of the index between 83 and 

 88. G. Retzius adds to this information the interpretation that his 

 father left a space between the tjpical measures, fixed for the two 

 groups; he fixed centres, round which the various sizes of the skull 

 can be arranged. 



If this should be so, one might expect that, in case a population 

 contained besides dolichocepalic also brachjcephalic race-elements, 

 the indices calculated from raanj observations, being united in a 



1) G. C. Hurst. Mendelian Characters in Plants, Animals and Man. S. 192. 

 Mendel Festschrift in Verb. d. nat. forsch. Ver. in Briinn. 49. Bd. 1910. 



-) E. Fischer, Die Rehobolher Bastarde und das Bastardierungsproblem beim 

 Menscben. Jena 1913. 



s) 1. c. p. S. 18. 



