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life. On examining a vessel of water brought from the canal, I discovered, in 
about a fortnight’s time, a rare and beautiful Stephanoceros , several Melicertce , 
Paludicella, and young Cristatellce. Paludicella, like Fredericella , is an 
exception to the rest of the family, being perennial. — Vide Annals of Natural 
History, No. xcix. 
The Nevj and TJnfigured Birds of America will be fully described in the 
forthcoming work of Mr. D. G. Elliot, of New York. This work is to be issued 
in parts, 19 by 24 inches in size, containing each five plates coloured by hand, 
with a concluding part, of text ; price for each part, 10 dollars. Only 200 
copies will be published. Mr. Elliot is author of a monograph of the Pittidce , 
or ant-thrushes, in one volume, imperial folio, with 31 plates ; and of a mono- 
graph of the Tetraonince, or Grouse tribe, in one volume, with 25 plates. In 
each, the birds, with only two exceptions, are of life size. 
The Physiology of the Fish's Eye. — A very elaborate paper, descriptive of 
the anatomy of the fish’s eye, has been published by Dr. Henry Fripp. We 
cannot here go into the minute details of the anatomy of the eye in fishes, but 
we give the following conclusions as those at which the author has arrived : — 
1. That the fish’s vision is clear for near objects, and that the great refractive 
power of the lens (a prolate spheroid having great density of substance) is 
adequate to the production of a defined picture at short focal distance, even 
when rays of light pass through so dense a medium as water ; objects in the 
air near the water being seen also, just as if they touched its surface at 
the point where the ray is bent. 2. That no “accommodation” such as is 
known to exist in the human eye, for the perfect definition of objects at a 
distance, occurs in fishes — or, at least, is not provided for in the same manner ; 
the passive state of the fish’s eye being that in which it is enabled to see near 
objects, no active or physiological change appears necessary for ordinary 
vision, whilst physical dispersion of light on the water renders distant objects 
less liable to excite attention. 3. That the iris has no power of reflex action on 
stimulus of light, and its immobility is in harmony with the optical deficiency 
of “ accommodation” and the physically deficient illumination of the waters. 
4. That the choroid gland is not an organ intended to assist or produce 
“ accommodation” of focal distance of the lens, but that its vascular charac- 
ter, and the absence of any muscular or gland element in its composition, 
lead necessarily to an interpretation of functions directly relating to the 
static condition of the circulating fluid, and the changes of dynamic force 
exerted by the heart under varying pressure from without on the fish’s body 
That, in fine, by such an arrangement (analogous examples of peculiarities in 
the venous circulation of mammals and other animals dwelling in the water 
being well known), protection to the delicate tissues of the eye is afforded in 
the compensation balance of pressure within and without the circulating 
system. 5. That there results from the globular shape of the eyeball, a 
secondary reflection of rays of light from the bottom of the eye against the 
inner pigmented surface of the choroid, which may perhaps intensify the 
retinal action, and probably stimulate the cells of the pigment membrane to 
secrete their molecular pigment from the venous flexuses of the choroid.— 
Vide Proceedings of the Bristol Naturalists' Society. 
The Metamorphoses of Insects . — In the interesting and instructive lectures 
which Sir John Lubbock delivered in the Royal Institution, the following 
