Cuar. X.] SWORD-FISHES. 329 
somewhat flattened at the base, but tapering to a sharp 
point. In strange inconsistence with its possession of so 
formidable an armature, the general disposition of the 
sword-fish is represented to be gentle and inoffensive; 
and although the fact of its assaults upon the whale has 
been incontestably established, yet the motive for such 
conflicts, and the causes of its enmity, are beyond con- 
jecture. Competition for food is out of the question, as 
the Xiphias can find its own supplies without rivalry on 
the part of its gigantic antagonist ; and as to converting 
the whale itself into food, the sword-fish, from the con- 
struction of its mouth and the small size of its teeth, is 
quite incapable of feeding on animals of such dimen- 
sions. 
In the seas around Ceylon sword-fishes sometimes 
attain to the length of twenty feet, and are distin- 
guished by the unusual height of the dorsal fin. Those 
both of the Atlantic and Mediterranean possess this 
fin in its full proportions, only during the earlier 
stages of their growth. Its dimensions even then are 
much smaller than in the Indian species; and it is a 
curious fact that it gradually decreases as the fish ap- 
proaches to maturity ; whereas in the seas around Ceylon, 
it retains its full size throughout the entire period of 
life. They raise it above the water, whilst dashing 
along the surface in their rapid course; and there is no 
reason to doubt that it occasionally acts as a sail. 
The Indian species (which are provided with two long 
and filamentous ventral fins) have been formed into the 
genus Histiophorus; to which belongs the individual 
figured on the next page. It is distinguished from others 
most closely allied to it, by having the immense dorsal 
fin of one uniform dark violet colour; whilst in its con- 
