ZOOLOGY AND BOTANY, MICROSCOPY, ETC- 
103 
able to prepare lantern slides which show the natural beautiful colouring 
and not mere dark shadows. 
Preserving Medulla oblongata of Rabid Animals.* * * § — Dr. E. J. 
Frantzius has found that for the experimental detection of rabies, it is 
sufficient to expose the spinal marrow of the suspected animal, and, 
having removed a piece from the medulla oblongata, to place this in 
a bottle filled with either glycerin or sterile water. When properly 
corked and packed in a wooden case, it is ready for transportation. All 
other precautions are unnecessary. Pieces of the central nervous system 
of rabid animals treated in this way retain the virus so effectively that 
animals may be successfully inoculated after several weeks’ immersion. 
The instance of a brain immersed in glycerin remaining virulent on the 
152nd day is quoted. 
Detection of Blepharoplasts in Onoclea and Marsilia.j — Sections 
of Onoclea Slruthiopteris in paraffin prepared a year beforehand, fixed by 
1 per cent, chromic acid, and stained with cochineal-alum and Bismarck 
brown, were washed in xylol, absolute alcohol, and water, placed in 
1 per cent, chromic acid for 24 hours, and then stained by Flemming’s 
safranin-gentian-violet-orange preparation. Sections prepared in this 
way by Mr. W„ R. Shaw, displayed an excellent distinction between 
cytoplasm and nucleus in the antherozoids which had collected in the 
mucilage before the open archegones. Male and female prothallia of 
Marsilia vestita and quadrifolia were treated in the same way with great 
success. 
Killing and Preserving Marine Animals. | — Dr. H. 0. Sorby finds 
that by adding a small quantity of menthol to the sea- water in which 
marine animals are kept, they fully expand themselves, and finally die in 
a distended condition, and can be so preserved permanently in a 4 per 
cent, solution of formalin. In this manner he has preserved Synapta 
in its natural form and several species of sea-anemones beautifully dis- 
tended. The author has also more fully developed a method of killing 
some animals with diluted glycerin, which is afterwards removed by 
water, and has thus been able to mount sundry worms in Canada balsam, 
so as to preserve even the minute blood-vessels filled with the natural 
red blood. 
Technique of the Tuberculous Serum Reaction. §— For obtaining 
homogeneous cultures of tubercle bacilli suitable for demonstrating the 
agglutination phenomenon, MM. S. Arloing and P. Courmont recom- 
mend beef or veal bouillon with 1 per cent. jDeptone and 6 per cent, 
glycerin. The cultivation-flasks should be flat-bottomed, and the cul- 
tures should be frequently shaken. Cultivations from 8 to 12 days old 
are the most favourable for the reaction. 
For observing the agglutination phenomenon satisfactorily, it is 
necessary to use blood-serum only. The serum is obtained by means 
of special tubes, or by centrifuging if there be no clot in the tubes. 
With each serum three mixtures of different strengths are prepared, 
* Centralbl. Bakt. u. Par., l te Abt., xxiv. (1898) pp. 971-4. 
f Ber. Deutscb. Bot. Gesell., xvi. (1898) p. 178. 
t ‘ Floreamus’ (Sheffield), 1898, No. 4, p 68. 
§ Comptes Rendus, cxxvii. (1898) pp. 312 -5, 425-8. 
