34 



C. W. M. Poyntcr 



cand placed the frequency at 5 per cent. The first extensive study 

 was made by Cloquet, which, with others, is given in the following 

 table : 



TABLE SHOWING THE PERCENTAGE FREQUENCY OF ORIGIN OF THE 

 ORTURATOR ARTERY FROM THE EPIGASTRIC 



Name 



Cloquet 1817 



Breschet 1819 



Hesselbach 1819 



Quain 1844 



Schlobig 



Isaacs 1855 



Wyeth 1878 



Hoffmann 1878 



Hartmann 



Krusche 



Pfitzner 



Jastschenski I i 



D wight 1895 



Levi I 1902 



Poynter 



Date 



Total. 



No. 

 Obs. 



■500 



63 



64 



360 



112 



706 



52 



400 



180 



80 



226 



404 



500 



200 



400 



Percent- 

 age 



30.4 



19 



43-3 



31-4 



21 



18.3 



34 



32.5 



19 



20 



37-6 



24 



25 



25.2 



26.2 



4,044 



25-1 



Male 



24.4 



33-9 



28.4 



37-5 



34-6 

 28.3 



Female Right 



31-4 



29.8 

 34-2 



25-9 

 26.3 



23-2 



37-5 



33-3 

 33-2 

 23.8 



Left 



46.8 



34-2 

 26.8 

 26 



The question of an anthropological influence was raised by 

 Pfitzner and Dwight, but no definite conclusions can be drawn. 

 We may conclude that the anomaly will be encountered in one case 

 in four, that there is little sex difference, and that it is slightly 

 more frequent on the left side. 



So far no satisfactory embryological explanation has been made. 

 From my study I find that the vessel develops late, 25-35 mm. stage, 

 as a pelvic vessel and later passes out of the pelvis. Before it has 

 left the pelvis it develops a retro-pubic branch of some magnitude ; 

 this may join a similar branch from the deep epigastric, but I have 

 never established such a connection. In one embryo, 32 mm., I 

 found a well-developed artery from the internal circumflex in the 

 position of the extra pelvic portion of the obturator, a well-devel- 

 oped retro-pubic branch from the epigastric, and no evidence of 

 an obturator within the pelvis. It would seem that the examina- 

 tion of a reasonable number of embryos of about 30 mm. stage 

 should settle the mechanism of this anomaly. 



