516 



Investi- 

 gators 



Material studied 



TS 



CS 



a 



Number of 



24 presacral vertebrae 



Normal 



Normal 

 except 

 for cer- 

 vical 

 rib 



Ribs on 



20tli 

 vertebra 



Rib 

 lacking 

 on 19th 



verte- 

 bra 



Sacrum 

 with 6 

 verte- 

 brae 



Stade- 



RINI 

 BlANCHI 



Bardeen 



Ancel 



and 



Sencert 



Skeletons obtained 

 from the civil hos- 

 pital at Florence 



Skeletons obtained 

 from individuals of 

 the Province of Sci- 



Skeletons from the 

 dissecting rooms of 

 the Johns Hopkins 

 University, Balti- 

 more, Md., U. S. A. 



Skeletons from bodies 

 dissected at Nancy 

 France 



Adult skeletons. Sum- 

 mary 



All skeletons tabu- 

 lated. Summary 



1.4 

 0.8 



14.3 



12.5 



5.9 



3.7 



5.7 



4.6 

 4.6 



3) lo the skeletons of white females thus far specifically reported, 

 variation in the number of presacral vertebrae is less frequent than 

 in the male skeletons. Variation in the female negro spinal columns 

 is slightly greater than in those of the male negroes. 



4) In the negroes of Baltimore, in most of whom there is probably 

 an intermixture of white blood, variation in the number of presacral 

 vertebrae seems to be greater than in the white races. I have pre- 

 viously pointed out, however, that a tendency toward costo-vertebral 

 reduction seems more frequent in whites than in negroes (1900). 



5) There is an equal tendency toward reduction and toward in- 

 crease in the number of presacral vertebrae. Each condition has been 

 reported in over 4% of a thousand skeletons specifically examined. 



