508 SOMATOLOGY 



being recorded properly and with due deference to the laws of the 

 correlation of growth, will make possible a graphic representation 

 of the distribution of forms in certain groups which, hence, may 

 be characterized, and thus the subject may assist in a most mate- 

 rial manner a classification of types. In connection with the use 

 of this method, however, it must again be insisted that before it 

 will yield the greatest good, and especially before we may draw 

 conclusions which may not be controverted, it is necessary to solve 

 the problem as to whether muscular and social development modi- 

 fies individuals or whether their physical structure is due prima- 

 rily to heredity. While, as already pointed out, it seems highly 

 probable that social or geographical environment may and does 

 influence muscular development, which in turn exerts a certain 

 influence on the skeleton, yet never great changes of form result. 

 On the other hand it has been shown by Galton and Pearson that 

 heredity is the chief factor in accounting for the physical char- 

 acteristics of the individual. Only upon such a supposition, as 

 Boas has pointed out, may we account for the types found in the 

 northwestern area of the United States, where we find a similar- 

 ity of geographic and social environment, but diverse and easily 

 recognizable physical types. Nor can we account for the distribu- 

 tion of types in Europe except upon the belief that heredity has 

 been the chief factor. The data afforded by metrical observations 

 must therefore be regarded as supplementary to a verbal discus- 

 sion which at best is often vague. Furthermore, the measurements 

 used should be such as to contribute to the solution of the pro- 

 blem at hand. This use of measurements to supplement verbal 

 descriptions by defining more sharply certain peculiarities will 

 prove of the greatest value, but the measurements should be se- 

 lected with this end in view. In other words, the methods pursued 

 in metrical investigations should have a biological significance. 

 It is to be noted also that the averages have not an equal value 

 with that of tables wherein measurements are so arranged as to 

 show frequency of forms in the group or groups under considera- 

 tion. With s'ich a view we are able to see at a glance the distribu- 

 tion of forms, and thus determine the variability of the group. 

 From this knowledge we may arrive at an idea of what constitutes 

 the prevailing type, thus furnishing an idea of the degree of the 

 homogeneity and permanence of the type. Observations thus 

 made have additional value, for. they contribute toward the solu- 

 tion of certain problems, such as the tendency of distinct types to 

 persist, even though they have been crossed. Further analysis of 

 the distribution of measurements will afford the means of com- 

 paring the types of adjacent geographic areas, and help to deter- 

 mine the blood relationship of these types, and hence ultimately 



