THE HAMMER-HEADED SHARK. 



207 



THE remarkable fish depicted in the accompanying illustration affords a striking 

 instance of the wild and wondrous modifications of form assumed by certain creatures, 

 without any ascertained purpose being gained thereby. We know by analogous reason- 

 ing that some wise and beautiful purpose is served by this astonishing variation in 

 form ; but as far as is yet known, there is nothing in the habits of this species that 

 accounts for the necessity of this strange shape. 



The shape of the body is not unlike that of the generality of Sharks, but it is 

 upon the head that the attention is at once rivetted. As may be seen from the figure, 

 the head is expanded laterally in a most singular manner, bearing, indeed, no small 

 resemblance to the head of a hammer. The eyes are placed at either end of the pro- 



HAMMER-HEADED SHARK. Spbyralas zygxaa. 



jecting extremities, and the mouth is set quite below, its corners just coinciding with 

 a line drawn through the two projecting lobes of the head. It is worthy of notice, 

 that several of our commonest British insects those beautiful dragon-flies belonging 

 to the genus Agrion have heads modelled on a very similar principle, and there are 

 some exotic insects where this singular shape is even more exaggerated, the eyes 

 being set quite at the end of long lateral footstalks. 



This species attains to a considerable size, seven or eight feet being a common 

 measurement, and specimens of eleven or twelve feet having been known. Its flesh is 

 said to be almost uneatable, being hard, coarse, and ill-flavored. The Hammer-headed 

 Shark produces living young, and from the interior of a very fine specimen captured 

 near Tenby in 1839, and measuring more than ten feet in length, were taken no less 

 than thirty-nine young, all perfectly formed, and averaging nineteen inches in length. 



