THE ATLANTIC OCEAN. 205 
The use of these tendrils appears to be their entan- 
glement among the stalks of sea-weeds, and the con- 
sequent mooring of the egg in a situation of pro- 
tection and comparative security. Near the head 
there is a slit in the egg-skin, through which the 
water enters for respiration, and another at the oppo- 
site extremity by which it is discharged. That part 
of the skin which is near the head, is weaker and 
more easily ruptured than any other part; a provi- 
sion for the easy exclusion of the animal, which takes 
place before the entire absorption of the vitellus or 
yolk of the egg, the remainder being attached to the 
body of the young fish, enclosed in a capsule, which 
for awhile it carries about. The position of the ani- 
mal, while within the egg, is with the head doubled 
back towards the tail, one very unfavourable for the 
process of breathing by internal gills, and hence there 
is an interesting provision made to meet the emer- 
gency. On each side a filament of the substance of 
the gills projects from the gill-opening, containing 
vessels in which the blood is exposed to the action 
of the water. These processes are gradually absorbed 
after the fish is excluded, until which the internal 
gills are scarcely capable of respiration, How curious 
an analogy we here discover with the Frogs and 
Newts among the Reptiles; and how impressively do 
we learn the Divine benevolence, when we find that 
the object of so much contrivance and care is the 
dreaded and hated Shark ! 
In these latitudes the Hammer-headed Shark 
(Zygena malleus), a fish of singular construction, 
attains a large size. In most particulars it closely 
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