NUMERICAL VARIATION IN THE HUMAN SPINE. 287 



This seems a very good iustiince of the suppression of a praesacral vertebra, the 24th 

 being the fulcralis, though its arch is not typical. 



(I feel called npon to mention that this spine fell into two pieces, parting below the 

 lUth vertebra, which are now artificially joined. The accident happily did not occur in 

 the original mounting, but subsequently, so tliat it is certain that no vertebra has been 

 lost.) 



Group B. 



350. Cat. 9379-23. 



Female, white. C. 7, T. 11, L. -3, S. u, C. 5. 



There is nothing noteworthy in the neck. There are only 11 thoracic vertebrae. 

 The ribs are cut, but the 11th pair is probably larger than the usual 12th one. The 18th 

 is very nearly, if not quite, a typical last thoracic. The head of the rib is in about the 

 normal place for that of the last one, and the head of the rib above it for that of the penul- 

 timate. The change of the articular processes is below the 18th. The spread of the 

 lumbar transverse processes is irregular. The last lumbar (23d) has the appearance of 

 the penultimate. 



The 1st sacral is in some respects rather transitional. There is a distinct promontory 

 above it, and a slight secondary one below it. The transverse processes are too clearly 

 defined. While I Ijelieve it to be the fulcrafis, I nuist admit that there is a want of abso- 

 lute certainty. The arch is very thoroughly fused with the next vertebi'a on the right ; 

 less so on the left. The spinous process is too long. The articular processes descend onto 

 the 3d sacral. The interpretation of the lower part of the sacrum is rather difficult. There 

 are seven pieces ; but the last two are to be considered as coccygeal. A lower detached 

 portion of the coccyx probably consists of three pieces. The fusion of the first two pieces 

 both with each other and with tlie sacrum, is very thorough. Tliere are five pairs of 

 sacral foramina. 



Again in the absence of f-esh measurements we have recourse to the height of the 

 vertebral bodies. It will be seen that by transferring the 1st lumbar to the thorax, the 

 proportions will become a little more normal ; but in view of the reasons for considering 

 the 19th a lumbar it does not seem advisable to make the change. 



