520 



R A I A. 



THE E^GLE RAY (Myliobatis aquila). This is a 

 rare species upon the Brjtish coasts, though pretty 

 well known on the shores of the Mediterranean. In 

 form it differs much from all the other rays that we 

 have enumerated. The head is considerably disen- 

 gaged from the pectoral fins, so that the eyes, which 

 in most of the others are actually within the disc, are 

 in this one about midway between the anterior mar- 

 gins of the pectorals and the termination of the 

 muzzle. The muzzle is also short and truncated, the 

 eyes much farther apart from each other, and nearer 

 the sides, and the whole head has much more ihe air 

 of that of an ordinary fish than in any of the other 

 rays. In these there is some difficulty in drawing a 

 line of distinction in the disc between what is the 

 body of the fish and what are the pectoral fins, from 

 the gradual manner in which the one passes into the 

 other. But in the eagle ray the body of the fish can 

 be easily made out for the whole of its length, and 

 the pectoral fins have the appearance of what they 

 are in reality appendages. On the upper side the 

 body appears elevated above the pectorals, tapering 

 in a sort of spindle shape toward the caudal extremity, 

 and terminating in a very long tail, which tapers gra- 

 dually, and is very slender at the point. In the 

 distal, and by far the greater part of its length, it is 

 perfectly plain, without either spine or fin. It re- 

 sembles the tapering thong of a whip,, on which 

 account the fish is often called the " whip"-ray. 

 Toward the base it is different ; for there there is a 

 little lobe of fin, and under it a serrated blade like 

 that of the sting-ray in form, but not quite so large 

 in proportion to .the size of the fish. The pectoral 

 fins in this species are very tiny, pointed, and narrow 

 .in proportion to their length, which gives them much 

 of the character of wings. It is generally supposed 

 that, in the sting-ray, in this, and in all the rays that 

 have a single powerful serrated weapon, or an other- 

 wise simple and tapering tail, the weapon is either 

 renewed periodically, or provision is made for the re- 

 placing of it by another in the event of ks being 

 broken off; for a smaller one has been observed by 

 the side of the large one attached to the same base. 

 The eagle ray has no pointed teeth in the mouth, 

 though the jaws are abundantly supplied with both 

 teeth and muscles. The outline of the jaws is rounded 

 so that the one is capable of having a rolling or 

 grinding motion upon the other, for which reason the 

 fish is sometimes called the " miller." The , teeth 

 are very hyd, and nearly flat in their crowns, form- 

 ing a sort of mosaic pavement upon the jaws. 



This curious species is found in the Medi- 

 terranean, and in various parts, of the ocean, 

 especially in the Pacific and the southern seas, 

 where several other species having similar characters 

 are said to have occurred. All of these appear to be 

 very seaward and discursive ; and the character of 

 the mouth and teeth would lead to the supposition 

 that they feed upon Crustacea and shelled mollusca 

 much more than upon fishes, though it has been, 

 stated, but without direct proof, that they use the 

 caudal dagger in transfixing their finny prey, alter 

 having entangled it in the coils of the long tail. This 

 is, we think, very unlikely, and would require to be 

 established by direct observation, which, so far as we 

 are able to ascertain, has not been done. In the ab- 

 sence of such observation, we would say that it is 

 impossible. The tail, though long and flexible, is not 

 absolutely prehensile, and inast be regarded as an 



instrument for striking, not for grasping. Even sup- 

 posing that the tail could grasp, and that it actually 

 coiled itself round the supposed prey of the fish, where 

 is the force by means of which the weapon could be 

 made to inflict a wound under such circumstances ? 

 Neither it, nor any other spine or weapon with which 

 we are acquainted upon the body of any fish, has any 

 means of motion ia or of itself, independent of the 

 motion of the part upon which it is placed. It has 

 not an apparatus for protruding and withdrawing like 

 the sting of a bee, and, therefore, it can inflict no 

 wound, unless it gets its momentum from the muscular 

 action of the body and tail of the fish, ucting as one 

 whole. It follows, as a necessary consequence of tin-;, 

 that, in order to use the caudal weapon with effect, 

 the body of the fish must be free. In proof of this, 

 it will be seen that, both in the sting rays and the 

 eagle rays, the weapon is placed near the base of the 

 tail, where that organ is. thick and strong, can have 

 little motion in itself, and thus give but small mo- 

 mentum to any weapon, unless the whole body of the 

 fish moves. All this tends to show that the weapon 

 in the tail of these rays has really nothing to do with 

 the capture or the killing of that on which they feed, 

 any more than the electric or galvanic power of the 

 torpedos has to do with such a purpose. It is purely 

 a defensive weapon ; and the fact of its being so tends 

 to prove that these fish do not contend with formi- 

 dable prey. The law is general throughout all ani- 

 mated nature, that, wherever an animal is furnished 

 with defences, it is an animal more subject to be at- 

 tacked than disposed to attack. Those defensive 

 weapons never in the least assist in obtaining the food 

 of the animal. 



" Bulls aim their horns, and asses lift, their heels ;" 

 but neither the hums of the bull iior the heels of the 

 ass are of any service to them in the taking of their 

 vegetable food. The same runs through all the de- 

 fended animals : the insects which have stings never 

 use those stings for the purpose of killing or wound- 

 ing their prey ; and the lancet-fishes and others,* 

 which have a powerful defence in spines upon their 

 bodies, are most of them vegetable feeders, or feeders 

 upon animals of such small dimensions that the spines 

 could not possibly be used against them. There is 

 no reason why those rays which have their tails 

 armed with formidable spines should form an excep- 

 tion to this general law. We arc, therefore, war- 

 ranted in saying that they do not form an exception 

 to it ; and that the conjectures to the contrary are 

 altogether groundless, and calculated to mislead, iu a 

 manner far more serious than the individual case, 

 inasmuch as they are at variance with a principle of 

 natural history, from which there is no deviation in 

 nature itself. 



That the eagle ray ever made its appearance on 

 the British shores is a point not fully ascertained, 

 though, as the habits of the fish are understood to be 

 discursive, and it is certainly well organised for 

 vigorous swimming, it is by no means unlikely that 

 it should come into our seas ; but it does not appear 

 to be a very shoreward animal in any part of the 

 world. Some fragments have been noticed that were 

 supposed to bqlong to it, but 'the supposition rests 

 upon very slender foundation. The fish is so curious, 

 however, that it is ivell worth looking out for by 

 all who take an interest in the inhabitants and the 

 wonders of the deep. 



We shall close this brief sketch of the very 



