248 THOMAS DWIGHT OK 



i. e., below the 19th. Tlie sacrum is remarkable in two ways: the lateral masses of the 1st 

 piece rise very high, as though trying to join the last lumbar, and, while a small part of the 

 3d articulates with the ilium on the right, none of it does on the left. This accords with 

 the downward movement of the thorax and loins on the right. On the other hand the 

 sacrum is normal in having a very strong promontory and the conjngata vera on the 3d. 

 All the .sacral and coccygeal vertebrae are fused. There are probably five of the latter. 

 The measurements and proportions from the fresh spine are as follows. 



Length of 636. Average length, male. Proportions of 636. .\verage proportions. 

 Neck 12.7 cm. 13.3cni. 20. 5^/^ 21.5 f/^ 



Back 29.3 28.7 47.3 46.3 



Loins 20.0 19.9 32.2 32.2 



Total 62.0 61.9 lOOO lOO.O 



It is clear that the 20th vertebra, as far as proportions go, must be called lumbar in 

 spite of its aping the thoracic region on the right. Very interesting are the concomitant 

 changes in the spread of the lumbar transverse processes; but what is peculiar and not 

 so easy to account for is the apparent effort of the sacrum to encroach on the loins, and 

 the fact that the 24th is somewhat of a penultimate. 



567. Cat. 9379-6. 



Male, white, aet. 59. C. 7, T. 13, L. 4, S. 6, C. 4. 



In this case the process has gone further and there are 13 pairs of ribs. The 13th ribs 

 have heads, that of the left one being ill marked. The right rib is 4.7 cm. long, the left 

 4.3 cm. Both are e^ddently more in series with the ribs above them than with the trans- 

 verse processes. The change of the articular processes occurs below the 20th vertebra. 

 Its spinous process, though intermediate, is lumbar rather than thoracic. The external 

 tubercle, especially on the right, is uncommonly developed in this vertebra. The spread 

 of the lumbar transverse processes increases to the 23d. The lateral masses of the sacrum 

 show a tendency (that did not appear in the preceding spine) to mark oft' transverse 

 processes. The 6th piece of the sacrum strongly suggests a fused coccyx. The 3d sacral 

 has a considerable surface articulating with the ilium. The conjugata vera is probably 

 at the 4th sacral. It seems as though the thorax were encroaching on the loins; never- 

 theless the proportions clearly require the 20th vertebra to be con.sidered thoracic in 

 spite of its lumbar peculiarities. 



These four cases illustrate what may be called the instability of the region at the 

 junction of the back and the loins. It is curious to see how similar the conditions of the 



