282 
Mr. Earle on the 
marrow, are much more early manifested, and are gene- 
rally far more serious in their consequences when the dorsal 
vertebras are affected, than when either the cervical or lumbar 
are the seat of disease. In the former case, the slightest 
congestion or effusion is often productive of serious symp- 
toms, from the canal being smaller and more completely 
filled with the marrow and its membranes ; whilst, in the 
latter description of cases, from the greater capacity of the 
canal and looseness of the membranes, considerable effusion 
may exist, without, at first, producing any marked symp- 
toms, more particularly in the lumbar region, where other 
circumstances concur in rendering the effect of pressure less 
sensibly felt ; to enter into a description of which, would be 
foreign to the object of this paper. 
As it is difficult to convey any clear idea of complicated 
forms by words, I have subjoined a sketch of some cervical 
vertebras in birds, with a description of the different parts. 
EXPLANATION OF PLATE XXX. 
Figure 1. Represents an anterior view of a single cervical 
vertebra. 
Fig. 2. A posterior view of the same. 
Fig. 3. A lateral view of the same. 
Fig. 4. A front view of two vertebrae articulated together. 
Fig. 5. A back view of the same. 
The letters of reference are the same in all the figures. 
A. The body of the vertebra. 
BB. lateral processes. 
C C. Styloid processes, with tubercles near their base, which 
restrain the motion of the vertebrae in the anterior direction. 
