OF THE SWORDFISH. 
part of the eye, on the outside of the choroid, and near the 
margin of the uvea. Blainville thinks he has observed 
ciliary processes in the eye of the Squdlus maocimus. At 
the place where the optic nerve penetrates the inner layers 
of the choroid, it has a very contracted and strangled ap- 
pearance ; and the retina which it forms, is proportionally 
the most bulky I have yet met with in any animal. The 
retina forms a thick pulpy coat, of a bluish- white colour, 
and becomes more thick and opaque as it advances towards 
the uvea, near the base of which it terminates by a smooth 
and even margin. We observe a straight white line or fissure 
extending, on the nasal side of the eye, in this animal, from 
the entrance of the optic nerve to the base of the uvea, 
along the inside of the choroid coat. Along the whole of 
this line the retina is firmly bound to the choroid coat, and 
it has no connection with the choroid at any other part. 
This remarkable appearance has the closest resemblance to 
the long fissure of the choroid through which the retina 
enters in the class of birds, but is very rarely met with in 
fishes. The eyes of the cod, the haddock, and many other 
osseous fishes, present no appearance of this kind, but have 
the retina quite free round the optic nerve. The retina 
appears to form a larger mass than could result from the 
mere expanded filaments of the contracted part of the optic 
nerve. The pulpy external layer of the retina is so thick 
in the Swordfish, particularly near its anterior termination, 
that it can be torn with the forceps, like cellular substance, 
into several layers. The white membrane or ligament, cor- 
responding to the pecten of birds, already discovered by 
Blainville, in six dififerent genera of fishes, is strong and 
distinct in the Swordfish, proceeding from the anterior end 
of the fissure of the choroid, through which the retina en- 
ters, to the capsule of the lens. Although the lens is a so- 
lid sphere, an inch in diameter, the pecten is so firmly at- 
