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same type as those of the vagus nuclei. More frontally the cells in 
the connecting bridge increase in number and soon both vagus 
nuclei form with the motor commissural nucleus, dorsally from the 
central canal, an elongated transverse nucleus column which thickens 
at both sides. In several sections this transverse cell-column is of 
uniform thickness, with the exception of the extremities, where the 
connection with the lateral nuclei occurs. (fig. 2). Ninety sections 
caudally from the calamus the connecting nucleus ceases, the lateral 
side of the dorsal motor vagus nucleus is then noticeably thicker and 
towards the calamus this side dips in a ventro-lateral direction 
(fig. 3). Here too, as in other animals, it may be noted that in the 
ventro-lateral portion of the nucleus, numerous cells occur of a larger 
type than in the rest of it. 
X Dorsal motor vagus nuclei and commissural motor X nucleus 
in the camel; b = bloodvessels, c = canalis centralis. 
Fig. 3. a = aberraut bundles, 5 = bloodvessels. 
A nucleus motorius commissuralis vagi has never yet been met 
with in any other animal: as we shall presently see it also occurs 
in the lama. The connecting nucleus lies principally in the region 
of the commissura infima, the decussation of the tractus solitarn, 
the sensory glossopharyngeo-vagus tracts. 
