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the transverse processes of the dorsal vertebrae, will be found, 

 even in man, to exist in the lower dorsals together with a trans- 

 verse process and a rib ; and in many animals (the Beaver is a 

 good example) they are found the whole length of the dorsal 

 region coexisting with ribs and transverse processes, so that the 

 tubercle of the lumbar vertebra cannot be properly called a 

 transverse process, nor the transverse process a lumbar rib ; and 

 the lumbar transverse process may still be considered, as Owen 

 maintains, the homologue of the dorsal transverse process. 



Moreover, there is just as good reason for making a " tuber- 

 cle " to the inferior as to the superior articulating process of the 

 lumbar vertebra ; and in many cases the inferior tubercle is the 

 larger ; the tubercle is not characteristic of a lumbar vertebra, 

 as it is found in many mammals the whole length of the dorsal 

 region ; if it merits any special name it may perhaps be included 

 under the general term " diapojjJiysisy But it rather seems 

 that this " tubercle " is of secondary importance, non-essential 

 as a characteristic of any kind of vertebra ; as an inconstant 

 process, like the posterior spines of lower Mammals, for muscu- 

 lar insertions ; in man, for the insertion of the posterior aponeu- 

 rosis of the transversalis abdominis. 



Another reason for admitting that the lumbar transverse pro- 

 cess is the homologue of the dorsal and not a rib, will be found 

 on examining the sacrum. Immediately external to and parallel 

 with the median crest is a row of five small tubercles, in a serial 

 line with the so-called lumbar tubercles ; that these are not 

 transverse processes, but points for mere muscular and liga- 

 mentous insertions, seems to me evident by following them in 

 the sacrum and tail of the Beaver, where they are seen to be 

 only largely developed articular processes, surrounded by the 

 rough points always found where strong muscular insertions are 

 required, as, in this case, to move the powerful tail. In the 

 Beaver, especially in the tail, the articular processes, with their 

 tubercles, cease long before the transverse ; which last are very 

 much developed, and extend quite to the end of the tail, where 

 the vertebra is reduced to a mere centrum ; it would be hard to 

 believe that these last are caudal Wis, which they must be, if the 

 tubercles are called transverse processes. 



In the human sacrum, also, the lowest pair of these tubercles 



