. Zoölogy [microform] : descriptive and practical. Zoology; Zoologie. »54 I'i! u '.rt Practical it. If the eye be held In the hand while trying to cut its tough outer "oat, the jellylike contents are easily squeezed out, ruin- ing the dissection. Let the eye rest on the board aU the time, and after first cutting into the cornea it is not necessary nor ad- visable to touch it with the fingers. When studying the lens, be very careful to tip it up gently and compare its front and back surfaces before removing it from the eye. 1. Lay the eye on the board, with the cornea uppermost.
. Zoölogy [microform] : descriptive and practical. Zoology; Zoologie. »54 I'i! u '.rt Practical it. If the eye be held In the hand while trying to cut its tough outer "oat, the jellylike contents are easily squeezed out, ruin- ing the dissection. Let the eye rest on the board aU the time, and after first cutting into the cornea it is not necessary nor ad- visable to touch it with the fingers. When studying the lens, be very careful to tip it up gently and compare its front and back surfaces before removing it from the eye. 1. Lay the eye on the board, with the cornea uppermost. Hold the eye firmly with the thumb and fingers of one hand; with the thumb and forefinger of the other hand hold the blade of the scalpel half an inch from its tip; with a steady motion push the blade horizontally through the cornea, near its edge. 2. The liquid in the cavity back of the cornea is the aqueous humor. 3. Slightly enlarge the cut horizontally; then with the forceps take hold of the upper edge of the cut, and with the scissors cut around the margin of the cornea and remove it. 4. The dark membrane now exposed is the iris. Pinch the eye slightly at the sides to make the iris show more distinctly. The hole in its center is the pupil. With the forceps raise the edge of the iris around the margin of the pupil to see that it is here unattached to the structures underneath. Observe the color and markings of the iris. 5. From one end of the pupil cut outward to the outer margin of the iris ; then cut around its outer margin and re- move it. Observe the color and markings of the posterior surface. 6. The body now laid bare is the crystalline lens. Touch it. 7. Lay a piece of newspaper i-/ose to the eye, on which to receive the lens, which sometimes pops out suddenly. With a very sharp blade make a quick, light gash across the surface of the lens to cut through the thin coat which envelops it, the lens capsule. Usually the lens may be made to come out by applying gentle p
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectzoology, bookyear1903
