SEA-BATS AND DORIES 



623 



young of the horse-mackerel seeking shelter beneath the " umbrella " of a jelly-fish till they 

 are big enough to defend themselves. 



But the most remarkable members of this family are the SEA-BATS. Few in species and 

 confined to the Red Sea, Indian Ocean, and Western Pacific, they are nevertheless in those 

 regions very common. Although not used as food-fishes, they are of extreme interest on account 

 of their shape, which is nearly oval and much compressed from side to side, and the form of 

 their fins, which in some species are excessively developed. Young sea-bats differ markedly 

 from the adults in the much greater length of the fin-rays, so much so that they have 

 frequently been described as distinct species. 



We pass now to the DORIES, which recall the Sea-bats in the oval and compressed form 

 of the body. The resemblance to sea-bats is, indeed, so close that the latter are frequently 

 described as dories. The mouth of the members of this family is so constructed that, 

 when opened, the upper jaw is thrust forward, and the whole mouth forms a kind of long tube. 

 Dories inhabit the seas of the temperate regions, two species being fairly common in British 

 waters. The best known of these two is perhaps the JOHN DORY, the largest specimens 

 of which attain to a weight 

 of 18 Ibs. Mr. Cunning- . 

 ham has described the very 

 peculiar way in which the 

 dory captures its prey. " It 

 does not," he writes, " over- 

 take it by superior speed like 

 the mackerel, or lie in wait 

 for it like the angler, but 

 stalks it and approaches it 

 by stealth. It is able to do 

 this in consequence of the 

 extreme thinness of its body 

 and the peculiar movement 

 of its hinder dorsal and 

 ventral fins. The dory places 

 itself end on towards the fish 

 it desires to devour, and in 

 this position it is evident 

 that it excites no alarm on 

 the part of its prey. The 

 appearance of the dory, seen 

 in this way, is a mere line 

 in the water, to which no 

 particular significance can be 

 attached. I have not par- 

 ticularly noticed the effect 

 of the ribbons of membrane 

 which project from the dorsal 

 fin. But I have observed 

 that the movements of the 

 dory are very gradual, except 

 in turning; it alters the 



position of its body by a n,,,t, ir. saviii..K.*t,f.z.s.] 



turn of the tail or side-fins, LONG-FINNED DORY 



and then SWimS forward by nh ifeclei cmc iy resembles a fossil form. It has nothing to do -with the True Dories, but is 



vibrating the Second dorsal one of the Coral-fahcs, and is placed here for the sake of contrast 



