ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 849 



handle, and a human hair mounted so as to form a small loop. Also 

 a " lifter " made of a " thick " thin glass cover, about f inch diameter 

 (this is more convenient if three of its sides are squared), cemented 

 to a piece of glass tube i inch diameter, and i inch bore, by filling 

 about ^ inch with broken shellac, to be carefully melted, and then 

 placed on the square edge of the cover, which should be hot. 

 Chemicals : nitric acid and chlorate of potash, and distilled water. 



The modus operandi is as follows : select, say a medium-sized 

 Deutzia leaf, cut out a square, or any other shape, but take care to 

 leave none of the margin, half fill the saucer with equal parts of 

 nitric acid and water, and to this add a small pinch of the chlorate of 

 potash, and gently boil over the lamp ; carefully watch the leaf, and 

 when the upper and lower cuticles begin to separate remove them by 

 means of the lifter into a watch-glass filled with distilled water ; the 

 two cuticles will sometimes separate of themselves, but much more 

 frequently require a little manipulation with the bristle to separate 

 them : this may be done by carefully inserting it between them. 

 When separated, float the lower cuticle * on a thin cover, and with 

 the hair loop gently scrape off any remains of fibre, &c. The upper 

 cuticle may be cleaned whilst floating by scraping the under surface 

 with the loop ; when clean float on to a glass slip. It is usually very 

 difficult to turn the cuticle over, and as it is always desirable to have 

 the external surface uppermost, it is necessary to mount one on the 

 cover and one on the slide. A more difficult but better plan is to 

 leave one of the margins of the leaf intact, and when clean float both 

 cuticles on to the slide ; when dry place the cover or the slide in 

 turpentine, and mount in Canada balsam. The siliceous cuticles of 

 Equisetum stems, barley-straw, cane, rice-husks, may all be obtained 

 by this process, but they will not bear drying ; they must, therefore, 

 be removed first to strong methylated spirit, and then ether, and 

 lastly turpentine. 



Mounting RapMdes.f — Mr. S. A. Webb gives the following 

 process for obtaining and mounting raphides : — 



" The hanging plant known as ' Wandering Jew ' (Tradescantia) 

 contains myriads of these needles. Place a slide upon the turn-table, 

 cut oif the stem of the plant transversely (somewhat obliquely j, and you 

 will find the juice forming a half drop on the cut end. Set the table 

 in motion without delay, and place the drop on the cut end upon the 

 centre of the slide, slowly moving it outward as the table turns, so 

 that it shall not twice pass over the same sjDot, until you have formed 

 a scroll-like circle with the juice of about | inch diameter. Let the 

 slide remain fifteen or twenty minutes, place a drop ot fresh balsam 

 upon the centre, and place upon it a half-inch cover-glass. Let the 

 cover sink down slowly until it is in contact with the balsam 

 throughout. If not level, press it gently, so that the balsam shall 

 fill out handsomely. Set it away, but do not heat it. It will require 

 some time to harden, but if in haste to use it, as soon as the balsam 



* By Tipper and lower cuticle is meant that which may be upwards or down- 

 wards in the saucer. 



t Amer. Men. Micr. Journ., ii, (1881) p. 71. 



