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 e^sr, 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 tc| 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 Eeptiles; 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 

 (Zygcena malleus), a fish of singular construction, 



attains a large size. In most particulars it closely 



s 



