218 PRACTICAL NOTES ON HISTOLOGY. 



wood and eosin, or logwood and picro-carmine, and mounted in 

 Canada balsam. 



Lachrymal Gland can be hardened in alcohol. One-sixth per 

 cent, chromic acid, or a mixture of spirit and a half per cent, 

 solution of chromic acid, equal parts of each ; and in a day or 

 two place in spirit. Osmic acid, one-fourth per cent., is a good 

 hardening agent, and small pieces should be teased in glycerine 

 and mounted. 



Sclerotic— Agents : — Either spirit, Miiller's fluid, or chromic 

 acid, one-sixth per cent., of which take 2 parts, and spirit 1 part. 

 Stain in logwood and picro-carmine and mount. 



Tenon's Capsule. — Take a fresh eye and remove all the adher- 

 ing mass of tissue except the eye-muscles, leaving the loose con- 

 nective tissue. The eye thus cleared is rinsed in distilled water 

 and a few drops of nitrate of silver solution poured over the 

 posterior part. After about three minutes rinse off the silver by a 

 stream of distilled water, and place the eye in water in the sun. 

 When stained, remove and fasten under water to a loaded cork 

 by a long pin passed through the cornea, and a piece of the 

 capsule of Tenon is dissected off the globe, floated flat on to 

 a slide, and removed from the fluid. After the excess of water 

 has been got rid of_, the piece is covered by glycerine, and 

 examined for the epithelioid markings. 



Lamina fusca. — The epithelioid layer lining the Lamina 

 fusca is also prepared by nitrate of silver. Dissect a square piece 

 of the sclerotic from a fresh eye ; the convex outer surface of it 

 is then pressed and made concave, dip in distilled water, silver 

 solution two minutes, rinse in distilled water, transfer to spirit, 

 place in sunlight with the inner surface, or Lamina fusca, upper- 

 most. When stained brown, place in water, wash well, and mount 

 in glycerine. The Lamina fusca may be seen in eyes prepared in 

 Miiller's fluid. Pin a small piece of the sclerotic under weak 

 spirit, equal parts water and spirit, dissect off the Lamina fusca 

 from its inner surface, and float on to a slide ; allow the spirit to 

 evaporate, so as to leave the delicate membrane moistened only 

 with water. Cover the preparation and add a little glycerine 

 to the edge of the cover-glass. 



