The spinous class of fishes is more prolific than any other animal.
In the first of these sub-families the tail is smooth, or unarmed, and in the second it is spinous.
Those which spring from the posterior of each arch are the spinous processes.
The back bone receives its name, spine, or spinal column, from these spinous processes.
Spinous process, a process or bony protuberance, resembling a spine or thorn, whence it derives its name.
These consist, when fully formed, of a plate bearing a spinous projection.
The spinous point gradually forces its way through the epidermis, so as to project freely at the surface.
Its superior surface presents a crest, formed by the fusion of the spinous processes of the vertebræ which form it.
The summits of the spinous processes of the vertebræ alone give form to the superior median border of the trunk.
The most marked characteristic of the dorsal vertebræ is furnished by the spinous processes.