ENCEPHALOCELES AND OTHER ABNORMALITIES. 



97 



lumbar and the five sacral vertebral bodies are well formed, as are the transverse 

 processes of all the lumbar vertebne and the partes laterales of the sacrum (figs. 

 10 and 12). The first four lumbar arches are everted, as are the thoracic arches, 

 though individually they are distinct and not fused. The fifth lumbar and the five 

 sacral arches are incomplete, but project medially toward one another and are not 

 everted. The lumbar column is 4.3 cm. long and the sacrum 3 cm. in length. The 

 coccyx is composed of four segments, which measure 1.6 cm. and are bent to the 

 left. In studying the proportions of the vertebral column, Aeby's tables of relations 

 in normal vertebral columns in the new-born were used, with the results shown in 

 table 1. 



TABLE 1. Comparison in millimeters of llu; vertebral lengths of specimen with those 

 given by Aeby for normal new-bnrn. 



A comparison of these vertebral lengths shows the lumbar portion of this 

 specimen to be within the limits of normal, though near the minimal margin. The 

 cervical portion is less than half, and the thoracic portion a trifle more than half 

 the length of the normal. Aeby gives 26.4 mm. for the transverse diameter of the 

 atlas, 12.2 mm. for the width of the body of the sixth thoracic vertebra, and 17.5 

 mm. for that of the fifth lumbar. In this specimen the lateral limits of the fovese 

 are 31.0 mm. and the width of the transverse processes of the atlas 38.0 mm. The 

 width of the vertebral plate in the midthoracic region is 23 mm. and the width of 

 the fifth lumbar vertebra is 21 mm. These differences show an irregular widening 

 process to have taken place in the vertebral bodies themselves, the change being 

 most marked in the thoracic and cervical regions. The absence of lateral pressure 

 from ununited arches must have been an important factor in this broadening 

 process. 



There are twelve ribs on each side which have undergone considerable disturb- 

 ance. On the right, the first six are fused near their bases (figs. 10, 11, and 15). 

 The second rib terminates at the end of its proximal third in a plate of bone by which 

 it is joined to the first and third ribs. On the left, the fifth to ninth ribs are crowded 

 together in their proximal half (figs. 10, 12, and 15). The fifth and sixth have but 

 one costal cartilage between them. The sixth and seventh ribs are fused for a few 

 millimeters just proximal to their termination. Further fusion occurs in pairs 

 at the bases of the following ribs: on the right, between seventh and eighth, ninth 

 and tenth; on the left, between the first and second, third and fourth. This shows 

 on the ventral surface in figure 15. 



The sternum, as seen in figure 16, has four ossification centers near the median 

 line at the level of the first costal cartilage and of the first, second, and third left 

 intercostal spaces. There are six costal cartilage connections on each side. The 

 last on each side, however, belongs to the seventh rib. The discrepancy occurs 

 on the right side through the aborted second rib and on the left side through the 



