The British Association— Section H—Anthropology

Abstract

Prof. W. Turntr read a paper on The Index of the Ptlvic Brim as a Basis of Classification.—That the inlet to the human pelvis presented variations in outline and in the proportions of its conjugate and transverse diameters has been recognised since the publication by Vrolik in 1826, and by M. T. Weber in 1830, of their important memoirs on the pelvis in certain races of men. In 1866 Zaaijer, of Leyden, in his study of the pelvis in women of Java, recognr ed differences in form in women of the same race, and he expressed these differences numerically, taking the transverse diameter as —100, and then multiplying the conjugate diameter by 100, and dividing by the transverse; the numeral so obtained is the index of the pelvic brim, or “pelvic index.” By applying this method to the pelvis in different races of man, a classification of races based on the index of the brim may be framed. In carrying out this method the male pelvis should especially be studied, as in women the pelvis, for sexual reasons, does not present such wide divergences in the form of its inlet as in men. To give precision to the classification, it will be advisable to employ special terms, and in order as far as possible to bring these terms into accordance with those employed in the classification of crania based on differences in the relations of the length to the breadth of the skull, Greek terms wdl be employed. Thus dolichopellic will signify a pelvis the conjugate diameter of which is longer than the transverse, or closely approaching to it; platypellic, a pelvis in which the transverse diameter greatly exceeds the conjugate; and mesatipellic, a pelvis in which the transverse diameter is not so greatly in excess of the conjugate. Owing to the comparatively limited number of pelves in the different races of men which have been measured, either it may not be possible to fix definitely at present the numerical limits of each of these groups; but the following were adopted provisionally by the author:- dolichopellic, a pelvis with brim index above 9′5; platypellic, one with brim index below 9′0; and mesatipellic, a pelvis with a brim index between 9′o and 9′5, both inclusive. The number of pelvic measurements from which the author drew his conclusions were comparatively few, but from these it would seem that the dolichopellic division contains Australians, Bushmen, Hottentots, Kaffirs, and Andarr.anese; whilst Negroes, Tasmanians, and New Caledonians are mesatipellic, and Europeans, Chinese, and probably American Indians belong to the platypellic group. When a pelvis has dolichopellic characters it approximates in the relations of its transverse and conjugate diameters to the form of the pelvic brim met with in mammals lower ihan man; and in the dolichopellic Australians, Bushmen, Kaffirs, and Andamanese, the length of the sacrum is on the average greater than the breadth, and this also is an animal character.