XITMERICAL VARIATIOX IN THE HnVIAN SPINE. 



is rudimeiitarv. The ri<jlit one measures 2.3 cm. and tlie 

 left one 4. cm. The heads of both are almost wanting and 

 rest on the pedicles rather tlian on the hodies. The left 

 one has more the appearance of a i-ili; liiit they both are 

 ill ;i line with tbe ribs and rest on transverse processes. 

 The 20th vertebra, to which tliev belong, has characters 

 of both regions. The spinous process is distinctly liiinbar, 

 and the chano-e of the articular surfaces occurs above it, 

 though in a rather transiticmal manner. The spread of the 

 lumliar transverse processes is greatest at the 3d lumbar 

 (23d) . The left transverse process of the 24th is that of a 

 penultimate, but the right one is not. The 20th vertelu'a, 

 sacralized on the right, is more asynnnetrical than in any 

 other spine of this class. Its body is separated from the 

 sacrum In an uncommonly small disc, and there is a sug- 

 gestion of a double promontory. On tbe left it presents a 

 thicker transverse process tlinii iisunl. bnt dot's not touch 

 the sacrum. On the right the sacralization is complete. 

 It seems at first as if on this side it were really the fnl- 

 crali)^, l)ut closer observiition shows it is not. Still it forms 

 a considerable p;irt of the auricular surface, which is com- 

 pleted by the two following vertebrae. Tiiis surface is 

 shorter on the left, being borne wholly on the 1st ;\iid 2d 

 saci'al vertebrae. There are but four sacr;d \ertebrae, 

 though what is evidently a 1st coccygeal is fused with 

 them. The lateral process of this latter is much more 

 developed on the left, so as almost to form a b)urtli sacral 

 foramen. The change of direction (coiijnt/dftt cera) is on 

 the 4tli sacral. The three following coccygeal vertebrae 

 were probably ;ill distinct in the fresh state. Two of them 

 are still mo\abh'. Tbe greati'r de\t'lopnieiit of the l-'Itli 

 rib, and of the lati'nd ])rocess of tlu' 1st cocc_ygeal, on the 

 left, is noteworthy, as it siiows an t'tfort to preser\'e a 

 iiornnd luiiibnr ;ind samd region. On the right, whei'e the 

 sacrum rises higher, tbe IMtli rib is smaller', and there are 

 four distinct sacral foramina. The interpretation would at 

 first seem to be : on the right 1 2 tlioracic vertebrae ; 5 lum- 



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