100 
THORNBACK RAY. 
of the eggs. A similar charge is laid against the trawl as 
regards several other sorts of fish; and it is to be regretted that 
what is otherwise a very valuable employment, and an excellent 
nursery for sailors, cannot be followed without inflicting injury 
on their brethren of the line and net; the opposite of which 
might be the case if some regulations regarding the times and 
distances of this sort of fishing were brought into action. 
This species is particular in the selection of its food; so that 
from being scarce it has become suddenly abundant on a change 
of bait; the pilchard and herring being amongst its choicer 
morsels; but it also feeds on crabs and other crustaceans in 
great abundance. 
It is sometimes known to come to the surface, even over a 
considerable depth of water; and in the month of March fish- 
ermen have noticed many at a distance of several miles from 
each other, where the water has been more than thirty fathoms 
in depth, stemming the tide without difficulty, but neglecting 
the offer of a bait. The Common Skate has been seen near 
the surface under the same circumstances; and it has been 
supposed that this occasional habit is in some way connected 
with the season of propagation. The egg cases are deposited 
in succession in May and June; and it has been remarked that 
females are met with in greater numbers than males. 
In an example three feet two inches in length, the tail 
measured eighteen inches and the breadth twenty-eight inches; 
the widest extent being behind the middle of the disk. The 
snout short, to the eye five inches and a half; the eyes separate, 
and elevated; spiracles large. The mouth five inches from the 
snout, with teeth rough at first, but generally flat like mosaic 
pavement; nostrils lobed. Border of the body from the snout 
at first rounded, then slightly concave to the extremity. Ventral 
fins small; dorsal fins two, rounded, and near the end of the 
tail. Body moderately thick, rough above, with large hooked 
spines scattered over the surface, the embedded root of each 
spine round and solid. Three rows of stout spines along the 
tail, the middle one running up the back. Colour of the upper 
surface, mottled with yellow, brown and dark, white below. 
The tints of colour vary, and in younger examples what at last 
appear mere blotches, are regular rings or waved lines. It is 
common to find some stout spines on the under surface, and 
