ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
381 
2 # 5 to 5 ju. The fixation of the sections on the slide may be effected by 
Gustav Mann’s albumen method. Mr. Ryder adds that a very simple 
form of this apparatus for holding the filter-paper in position may be 
obtained from Messrs. Charles Lentz and Sons, of Philadelphia. 
C3) Cutting-, including- Imbedding and Microtomes. 
Sectioning Fern-Prothallia.* — Mr. M. B. Thomas describes a pro- 
cess for imbedding fern -prothallia and other delicate objects in collodion, 
and sectioning with the microtome. Before imbedding the object must 
be well hardened and dehydrated. It is then placed in a solution of 
1*5 grm. gun-cotton in 100 ccm. of equal parts of ether and alcohol ; the 
liquid is slowly evaporated until solid collodion remains behind. The 
subsequent treatment is much the same as that of objects imbedded in 
paraffin. 
Universal Razor for Microscopists.| — Dr. Eternod has devised, for 
the use of students, a razor which can be used for cutting sections either 
Fig. 73. 
by hand or by the microtome. It is composed of the following parts : — 
(1) A special blade, (2) an aluminium handle, (3) a bolt for connecting 
c * The Microscope, 1893, pp. 167-8. See Bot. Centralbh, lxi. (1895) p. 317. 
^ t Zeitschr. f. wiss. Mikr., xi. (1895) pp. 465-9. 
