60 R- J- Anderson, 



proper dwelling place. Many people in England (Incl. Scotland and 

 Ireland) and America would welcome a more scientific explanation of 

 the facts noted by Professor Patterson with regard to the relative 

 numbers of unmarried males and marriageable females in Dundee. 

 The explanation is clearly that the stream of emigration proceeding 

 to the seaports divides (at Dundee for instance), the female portion 

 remains, the males go to other lands. It is not due, we are per- 

 suaded, to any attenuation of the occipital lobe. The varieties in the 

 cerebral convolutions are of especial interest in reference to the arterial 

 supply. The anomalies of the cerebral surface arteries must be of 

 very great importance, if the districts and subdistricts which they 

 mark off are the regions of convolutions and gyri, and especially so, 

 if the arterial meshes give a start to the convolutions as they bulge 

 on the surface by determining the position of the sulci, thus plotting 

 the convolutions; as a third lobe is added to a lung by a devious 

 azygos vein (Cleland). In this regard an apparently unimportant 

 modification of an artery may, arising from obstruction and anasto- 

 mosis, give rise to peculiar cerebral markings. The constancy of 

 arterial origins is remarkable, compared with the varieties, in the 

 larger arteries. Arteries are rendered so strong by the passage of a 

 blood -current, that it is easy to understand how potent they may 

 be in producing a variety. Treitz believed that the fold that guards 

 the opening into the Retroperitoneal Fossa is formed by the vessels 

 that lie hid in the fold, and that these vessels are instrumental in 

 keeping the fossa duodeno-jejunalis open so as to let a hernia (retro- 

 peritoneal) form. The variations in the presacral Region noted by 

 Rosenberg, Patterson, and others, have been explained as arising like 

 similar varieties in Birds and Reptiles, i. e. as casual deviations depen- 

 dent on causes that are much alike but differently distributed. The 

 erect attitude in man introduces new complications. Leaving out the 

 period of rest in sleep, the pose of the body is various in different 

 individuals. Soldiers, Artizans and many others have the erect posi- 

 tion predominant. It is the position of greatest ease in progression, 

 the natural position for Man, owing to his Cerebral development 

 (Turner); especially as the anterior limbs have been so modified as to 



