92 Modern Microscopy. 



Protococcus. This can be obtained by scraping the 

 bark of trees. Place it in a bottle of water, and let it 

 stand for a few hours ; now add a little copper solution 

 this will kill the specimens, and they will sink to the 

 bottom of the bottle ; pour off the water, and add more 

 copper solution. Now make a cell as for spirogyra ; take 

 up some of the protococcus in a dipping-tube and place 

 them in the cell ; wait a minute for the forms to settle on 

 the bottom of the cell, and then apply a cover-glass ; drain 

 off the excess of fluid, dry the slides with a cloth, and apply 

 a coat of cement. 



Volvox. Treat as above. 



Red Algae. The copper solution does not suit red algae ; 

 they must be preserved in dilute methylated spirit, or 

 dried between folds of paper. To mount same, remove 

 from the spirit, and soak in several changes of water until 

 all trace of spirit is washed away, then mount in glycerine 

 jelly. The dried specimens only require soaking in water 

 until they come off the paper. They are . also to be 

 mounted in glycerine jelly. 



Antheridia and Archegonia of Mosses should be 

 preserved in methylated spirit. Soak in water before 

 mounting, and if very hard, in dilute potash ; wash away 

 the potash with plenty of water, tease out the specimen 

 with needles on a slide, apply a few drops of glycerine 

 jelly and a cover-glass. 



Fertile Branch of Chara. Chara is usually very dirty ; 

 when so, wash well in repeated changes of water, and then 

 in very dilute acetic acid for a few minutes only ; then wash 

 again in water, and preserve in camphor water. 



Make a cell with shellac cement as directed above, place 

 a fertile branch of chara in it, and place under a dissecting 

 microscope or lens ; with needles clear away the leaves from 

 the archegonia and antheridia, fill the cell with camphor 

 water, and apply a cover-glass. 



When a deep cell is required for a specimen to be 

 mounted in acetate of copper, never use one made of any 



