DR. COBBOLD ON THE EYE OF THE COD-FISH. 145 
where it is accompanied by a blackish shade; discal point black ; 
exterior border cinereous, this hue attenuated hindward. Hind wings 
with a cifereous fringe. Length of the body 6 lines; of the wings 
16 lines. 
The structure of this species does not quite agree with the typical form 
of Nyssia. 
199. Nyssta? BIGUTTATA, n.s. Fem. Cinereo-fusca, alis anticis pal- 
lide cervinis, gutta discali nigra, spatio exteriore obliquo fuscescente 
intus linea nigro-fusca concisa marginato. 
Female. Cinereous brown, stout. Palpi porrect, very broad and obtuse. 
Antenne simple. Fore wings pale fawn-colour, excepting the oblique 
exterior part, which extends from near the tip of the costa to the mid- 
dle of the interior border, and is blackish brown and concise along 
its inner side ; discal dot black, rather large. Length of the body 5 
lines ; of the wings 14 lines. 
{To be continued. } 
Histological Observations on the Eye of the Cod-fish (Morrhua 
vulgaris), with especial reference to the Choroid Gland and the 
Cones of the Retina. By T. Spencer Cozsoxp, M.D., F.L.S., 
Lecturer on Botany, Zoology, and Comparative Anatomy at 
the Middlesex Hospital College. 
[Read March 6th, 1862. ] 
By introducing observations of this kind to the Linnean Society 
J am aware that I am treading a well-beaten path; but as there 
are still many points connected with the minute anatomy of the 
vertebrate eye which remain to be solved, I trust that the facts 
and opinions which I proceed to bring under the Society’s notice 
will obtain due consideration. 
With the exception of Mr. Nunneley’s researches, most of the 
recent investigations into the minute structure of the eyeball 
have been made after the organ in question had been steeped for 
a longer or shorter time in chromic-acid solutions ; and from this 
circumstance I think we have been frequently led into error as 
regards the precise character of the ultimate elements of the organ, 
although, in the hands of Hannover, Koélliker, and Heinrich Miller 
more especially, the relations of the component layers of the eyeball 
have been most satisfactorily determined. 
To take the vitreous humour, for example, it is quite clear that 
Hannover’s views (published in Miiller’s ‘Archiv’ for 1845) as to 
LINN. PROC.—ZOOLOGY, VOL. VI. 10 
