NUMERICAL VARIATION IN THE HUMAN SPINE. 293 



2.7 



•2.8 



Liimhav 3 2.5 2.6 



2.4 



i.i 



13.2 



Total 40.G cm. 44.2 cm. 



While the first pair of ribs is what are usuall}- known as cervical, it might be permis- 

 sible, in \dew of the fact that the subclavian artery on each side passed above them, and in 

 view of the large size of the 7th vertebra and of its transverse process, to say that one 

 cervical, rather than one thoracic vertebra, is wanting. This spine is remarkable as an 

 instance of irregular segmentation, one vertebra being suppressed, while the lumbar, sacral 

 and coccygeal regions are almost typically normal. Rosenberg has apparently overlooked 

 my previous description of this case, for in his paper ('99) he alludes to a similar but less 

 complete case of Gruber's; and does not seem quite convinced that the observation is 

 exact. According to his scheme this case is to be described as one with a primitive condi- 

 tion of the lower part of the neck ; while the lower part of the thorax and all below it 

 have reached almost the maximum of transformation in the direction of the future. It 

 may be questioned whether the almost typical condition of the lower half of the spine 

 (apart from the numerical position of the vertebrae composing it) does not point to a con- 

 dition that has suffered no change. Probably Rosenberg would reply that it is precisely 

 this question of the numeiical position of the vertebrae that is important. To express 

 this differently : let us suppose that the spine had been divided in the middle of the 

 thoracic region and the upper half lost. On examining the lower half all would agree 

 that it is practically a normal spine, because no one woidd know that the last thoracic is 

 the 18th vertebra, and the last lumbar the 23d. It would be taken for granted that they 

 are the 19th and 24th. It does not seem to me plausible that an excessive progress of the 

 ilium should have been accompanied by modifications that reproduce so nearly perfectly 

 the normal conditions. There is an error of the original segmentation. 



This spine furnishes two independent pieces of evidence in favor of ^dtalism. One is 

 the increase in size of the thoracic vertebrae, by which eleven more than take the place of 

 the normal twelve. The other is the development of the ligaments passing from the sides 

 of the odontoid to the atlas, thus retaining it in position and allowing it some motion. At 

 the same time mention should be made of the modification of the joints between the atlas 

 and the occiput. What made all these concomitant modifications but an influence within 

 the organism regulating the details of growth for the needs of the whole ? 



