332 PHYSIOLOGY CHAP. 



S. Sergi (1912) amongst the Italians, Albanians, Prussians, pre- 

 historic Egyptians, inhabitants of Tierra del Fuego, Peruvians 

 and Bolivians, show to be considerably deeper amongst all 

 civilised races. 



The retrosacral fossa is the cavity in the pelvis formed by the 

 posterior superficies of the sacrum, and laterally circumscribed 

 by the post-articular portions of the iliac bones. Sergi considers 

 these variations in the retrosacral fossa to be of " a physiological 

 nature, i.e. the expression of a functional correlation with a whole 

 system of different morphological conditions in the skeleton ; the 

 reduction of the retrosacral fossa is not peculiar to the Melanesians 

 (as is thought by Bolk), neither does it point to typical carriage 

 amongst those peoples, but rather to static and dynamic physical 

 conditions, common to all primitive peoples." He further re- 

 marks that similar differential variations in the skeletal system 

 of the trunk (vertebral column and ribs) were noticed at an earlier 

 date. In 1887 Sergi remarked that the curvature and degree of 

 torsion of the ribs of the inhabitants of Tierra del Fuego are not 

 the same as in Europeans, for which reason "their thorax is 

 laterally narrower than that of Europeans, and projects more 

 towards the front." 



Cunningham and Manouvrier noticed differences in the 

 characteristic curves of the vertebral column connected with the 

 erect position of the human form. In like manner it has been 

 observed that in the course of general development amongst 

 Europeans the retrosacral fossa, which is shallow in the infant, 

 becomes deeper and deeper during the first years of extra-uterine 

 life, just as the curves of the spinal column become more and more 

 marked. 



Hitherto the researches of anthropologists have been almost 

 entirely confined to the different parts of the skeleton (and more 

 especially of the skull), because the skeleton can be preserved 

 without difficulty for the purpose of such research. It is, how- 

 ever, obvious that somatic anthropology, like comparative 

 anatomy, which has achieved notable results by proceeding from 

 the study of the skeleton to that of the other systems and organs 

 (muscles, nerves, intestines, etc.), must in future investigate in 

 various human types the differential characteristics found in 

 the other anatomical systems, or rather in the soft parts. We 

 may mention that this study has been begun by several anatomists, 

 amongst others Chudzinski, Giacomini, and Loth, who have 

 studied the muscular system of negroes, and Adachi, to whom 

 we are indebted for an excellent work on the muscular system 

 of the Japanese. Loth has recently summed up the results 

 of these first researches, and drawn the following conclusions 

 therefrom. 



I. We must admit the existence of indubitable morphological 



