NUMEI.MCAL \ AKIATIOX IX THE HUMAN SPINE. 



:77 



exostoses iu the places of the intervertebral tUscs. The change of the articular processes 

 occurs hclow the last thoracic (ISth) vertehra. the spiue of which is decidedly lumbar. 

 The 6tli lumljar vcitebra is clearly luml)ai- on the right, and very thoroughly sacralized 

 on the left. There is a promontory l)otli al)()\e and below the body, which is all but com- 

 pletely co-ossitied with the sacrid vertebra below it. The lateral 

 mass on the left shows both a transverse and a costal element. 

 The latter ii[)pears to form so large a jiart of tiie aui-iciilar 

 surface that on tlie left this vertebra (tlie 24th) seems to l)e 

 the fiilcral is. The vertebra above it is on both sides very much 

 like a last lumbar. The spread of the lumbar transverse proc- 

 ess increases to the od, belcjw which it is pretty nearly the 

 same. The left transverse process of the 1st lumbar is smaller 

 than the right. The od sacral vertebra shows tlie transverse 

 depression across the body. It is doiiljttid if the auricular 

 surface of either side touches this vertebra. The coccyx consists 

 of four pieces. The 1st is well foi'ined ; the lower ones are con- 

 fused and distorted to the left. 



In this spine we see that the thorax has moved upward and that the Gtli vertebra is 

 a typical last cei'vieal. The 1st rib on the left is less like an ordinarv cervical one than a 

 ruLUmentary 1st thoracic. It resembles very closely the specimen of the latter in A-4 

 and in an imperfect specimen described later (noTD-oS) . 



It would seem, acccu'dinu- to Kosenberii''s views strictlv interpreted, that while this 

 spine is a pi'iniitive one in the neck, it is one of the future in the loins. He admits very 

 fraid\ly that the two processes working at the two ends of the spine do not by any means 

 always hold the lelation to each other that should be expected. Would it not be more 

 plausible to say that the change at the two ends of the spiue, instead of the discordant 

 action of two tendencies, was the simple action of one, — in other words, that the last cer- 

 vical vertebra beconung a thoracic, the last thoracic one becomes a lumliar, and the size of 

 the thorax is retained ? 



H-3. 



Groiqt U. 



Six cases of pai'tial sacralization of the oth liiml)ar (•J4tli). The' spines differ among 

 themselves in several details, as well as in the degree of sacralization ; but they are ai- 

 rana-ed acconhim' to the latter, which is sliu'lit in the lirst and almo.st complete in the last. 



