ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
161 
drying medium, more so than the one I use. In fact I am anxious 
to find some solvent which will evaporate faster, and yet, if possible, at 
the same time, to avoid much contraction. Obtain a white sample 
of balsam in liquid form, and take by weight in all cases, in a 
wide-mouthed bottle, balsam, 3 oz. ; turpentine, 1 oz. ; chloroform 
(pure), 1 oz. ; gently turn the bottle several times to mix well, and 
let it stand till free from air-bubbles and is thoroughly mixed. Pour 
out a small quantity at a time in a one dram bottle, and keep it 
covered with a cork, with a glass rod drawn to a point passed through 
it, or take a piece of glass rod and heat till soft, and press the two 
ends together so as to produce a flange. It is then easily wiped and 
cleaned with a rag moistened in turpentine. Caro is taken to lower 
the cover very slowly. As a question, may I ask if any one who has 
been to Europe and returned here with specimens, has noticed how tho 
climate causes great shrinkage to balsam mounts? As an instance, 
I have mounts of Cole’s studies, and special mounts of his, and I find 
now that the zinc white has let air pass through and ruined the 
mounts, in many cases I have had to remount them. I may say hero 
that I am not in favour of the usual white zinc cement, and recommend 
either brown varnish (Ward’s, Manchester, England), or Hollis’s gluo. 
The last is the best, for it may be used with immersion lenses, and 
it renders ringing unnecessary afterwards, which is a bugbear if you 
should be in a hurry to examine a specimen, which is often the case in 
medical work.” 
Mounting Arranged Slides.* — Mr. G. II. Bryan remarks : — “ I have 
recently discovered another use for tho ‘ pressureless mounting clips ’ 
which I described in the ‘ Journal of Microscopy ’ for Jan. 1890. I 
find, namely, that by their use it is possible to mount slides containing 
an arranged group of various objects, such as several plant sections or 
parts of an insect, with great ease. To do this, the objects are placed as 
nearly as possible in the required position in a drop of liquid balsam. 
On putting down the cover, it will generally happen that, even with tho 
utmost care, some of the objects will become displaced. Let the cover be 
now fixed between the jaws of two of my “ pressureless clips.” Then, 
by using several badger-hairs or bristles mounted in handles, and of 
sufficient length to be pushed right under the cover, the objects can be 
moved about in the balsam and brought into any required positions. 
If the specimens again become displaced during the process of hard- 
ening the balsam, the slide may be warmed and the objects pushed again 
by means of a hair thrust underneath the cover into the softened 
balsam.” 
Simple Method of fixing Paraffin Sections to the Slide.f — Dr. G. 
Lovell Gulland writes : — “ In Dr. Gaskell’s interesting paper ‘ On the 
Origin of Vertebrates from a Crustacean-like Ancestor,’ \ he describes a 
method (on p. 382) by which he succeeded in overcoming the folding of 
sections of the cranium of Ammocoetes. It consists in floating the 
series of sections on the surface of warm water, which flattens them, and 
* Internat. Journ Slier, and Nat. Sci., iii. (1891) p. 328. 
f Journ. Anat. and Physiol., xxvi. (1891) pp. 56-GO. 
i Quart. Journ. Micr. Sci., xxxi. (1890). 
1892. 
M 
