PLATE X (continued). 
Fig. 
profile, showing a small spur, by which possibly they adhere to the 
conoidal rods, though in the great majority this spur cannot be 
seen; they appear to be true globules. g. Conoidal rods and ovoid 
bodies become granular. 
10.—From duck. a@. Cylindrical rods, which are larger and more numerous 
than in the fowl; in one duck all the rods were cylindrical, aud many 
of them were surmounted by the ruby- and canary-coloured globules : 
there were none conoidal, except such as shewnate. 46. Conoidal 
rods from another duck. ¢. Ovoid bodies without coloured globules. 
d. Ovoid bodies with coloured globules. e. Ovoid bodies with a 
conoidal leg attached at the zzzer side ; this process becomes detached 
and breaks up into dises, as do the cylinders, while the more globular 
portion becomes granular; so that it is difficult to say whether 
these are ovoid bodies with a portion of rod and globule accidentally 
attached, or whether the ovoid bodies are not really altered conical 
rods deprived of the inner process. jf. Cylindrical rods and ovoid 
body with coloured globules accidentally attached. x 450. 
1].—From swan and goose. a. Conoidal rods with coloured globules. 4. 
Ovoid bodies with similar globules. c. Three of the rods altered. 
d. Coloured globules fusiform in shape. e. Strong cylindrical nerve- 
fibres in retina from swan, jf. Cylindrical and conoidal rods. gy. Ovoid 
bodies. %. Rods curled round so as closely to resemble ovoid bodies. 
2. Rod curled into hook at one extremity. x 450. 
12.—From Guinea fowl. a. Outer surface of retina with rods and globules 
in situ. 6. Coloured globules detached. x 450. 
13.—From green turtle. a. Long and short cylindrical rods, neither of 
which are very numerous. &. Conoidal rods, for the most part sur- 
mounted by a coloured globule. c. Ovoid bodies surmounted by 
coloured globules. d. Very nearly similar bodies without coloured 
globules. e. Ovoid bodies with a short cylindrical leg attached at 
inner side, intwo of them it is seen breaking off; they are surmounted 
by coloured globules. f These different bodies after the lapse of 
a few hours; immediately on the addition of water; and also from 
another turtle, which, before being killed, was in a very languid and 
feeble condition. g. Average size of ruby globules. 4%. Of canary 
globules. ¢. Three of these globules in profile to show spur which 
some appear to possess, but by far the greater number seem to be 
true globes; when not exactly in focus, as the globules of birds, 
they appear to have a nucleus, which, however, they have not. 7. 
Nerve- fibres forming a layer in retina. 4. Finely granular cells. 
x 450. 
14.—Turtle; form, size, and position of elements of outer coat of retina, 
showing the cylindrical and conoidal rods with the coloured globules, 
and at their base the ovoid bodies. x 450. 
15.—Section of retina of turtle. a. Rods. 8. Coloured globules. c. Ovoid 
bodies. d. Granular cells. e¢. Nerve-fibres and blood-vessels. (7. 
Transparent cells between last and the hyaloid surface. x 450, 
