206 THE OCEAN. 
resembles the species just noticed, but the head is 
widened out on each side into an oblong projection, 
at each extremity of which is placed the eye. The 
whole of this part has the form of a double-headed 
hammer or maul. Undoubtedly one result of this 
remarkable structure is a vast-increase of the sphere 
of vision; but why a fish so formidably armed, and 
endowed with such powers of motion, should be thus 
favoured, we are not sufficiently acquainted with its 
habits to determine. 
Another singular deviation from the general struc- 
ture is found in the Saw-fish (Pristis antiquorum), 
which is a shark with the head prolonged into a flat 
Tlammer-Suark (Zygena malleus), AND SAW-FISH (Pristis antiqguorum). 
