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bound on each side the sacral canal, and form the articulation 

 with the coccyx ; this would show that they are not transverse 

 processes, as these do not form articulations between contiguous 

 •neural arches^ and do not give origin to articulating processes. 

 Owen says, " it is peculiar to fishes to have articular processes 

 developed from the parapophyses," (transverse processes.) 



Tubercles on the transverse processes are well seen in the 

 dorsal region of Birds, where they are prolonged upwards and 

 downwards, often touching each other and forming foramina; 

 yet in this class, as in Mammals, ^Ae?/ coexist luithrihs and trans- 

 verse processes. In the Eagle the tubercles are large, and 

 nearly coalesce ; in the Puffin and Parrot, they are slender pro- 

 cesses which enclose complete foramina. 



Supposing, with Wilson, that the convergent tubercles and 

 transverse processes were prolonged, they would not enclose a 

 foramen homologous with the cervical vertebral canal. The 

 formation of this canal is excellently well shown, in the Alliga- 

 tor, to be due almost entirely to the forked origin of each rib of 

 the neck, the transverse process having comparatively little to 

 do with it ; the canal is mainly formed by the forks of the ribs, 

 and not by the union of a transverse process with a single costal 

 process, which would be the case, allowing Wilson's homolo- 

 gies. In the neck one of these forks is attached to the verte- 

 bral body, and the other abuts against the transverse process ; 

 in the dorsal region both forks are united to the transverse pro- 

 cess ; in Man, the outer or posterior fork being represented by 

 the " tubercle " of the rib, resting against the transverse process. 



It will also be seen that the cervical ribs in the Alligator are 

 prolonged by both an upward and a downward process, which 

 touch each other ; thus forming what may be called anterior 

 and posterior cervical foramina ; these are analogous to, and 

 perhaps homologous with, the anterior and posterior sacral fora- 

 mina ; the former are certainly formed by ribs, and, according 

 to Owen, the latter also. So that the argument of Wilson, that 

 the lumbar "tubercles," if prolonged, would form posterior 

 intervertebral foramina is of no weight as proving that they are 

 true transverse processes, since as we have a similar formation 

 produced by ribs ; — if it proves any thing, it proves too much, as 

 it shows equally well that they are transverse processes or ribs. 



