ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
109 
The granules increased in size and in a few weeks had become pretty- 
large yellowisli-wbite grains which penetrated within the substance of 
the agar so that they could only be removed with difficulty. Micro- 
scopical examination afterwards showed that the colonies grew radiatcly, 
forming branches and mycelia like some moulds do, whence it would 
seem highly probable that Actinomyces is a sort of mould fungus. This 
appearance does not resemble that of the club-shaped elements found 
in human pus and in the fresh pus and nodules of ruminants, but is 
identical with that of the nodules found in human organs or in human 
pus after treatment with caustic soda. 
In older agar cultivations bulb-shaped expansions formed on the ends 
of the filaments, but whether these were gonidia or an involution form 
the author cannot yet say. 
Two photographs from sections magnified 340 and 840 times were 
obtained as follows : — An agar cultivation three weeks old was cut up 
into small pieces and placed in absolute alcohol for 48 hours ; then for 
21 hours in 1 per cent, and afterwards for six hours in 5 per cent, jdioto- 
xylin solution. From these pieces sections were made in the usual way 
and removed from spirit to a slide, and when they were dry (20-30 
minutes) were stained by Gram’s method. The photographs were taken 
with Zeiss’s apparatus by sunlight. Zettnow’s light-filter was used and 
Attout-Tailfer’s isochromatic plates. 
Cultivation of Typhoid Bacillus in Sewer Water. ^—M. L. Olivier 
states that sewer water is a very favourable medium for the cultivation 
of typhoid bacilli ; they develope in it quite as well as in bouillon. 
(2) Preparing- Objects. 
Preparation of Cells for showing the Division of Nuclei and the 
Formation of Spermatozoa.f— For examining cell-fission, and the 
formation of semen in the hermaphrodite glands. Dr. G. Platner recom- 
mends immersion in the strong Flemming’s mixture. Fresh pieces of 
gland cut up small, if necessary, are placed in the mixture for an hour ; 
the fluid is then diluted with three or four times its bulk of water, and 
allowed to harden further for 24 hours longer. They are then thoroughly 
washed in the usual manner, and afterwards transferred to spirit of 
increasing strength. The best nuclear stain is logwood, and the author 
recommends Apathy’s modification of Heidenhain’s haematoxylin (hosma- 
tox. crystals 1, absolute alcohol 70, aq. dest. 30, the fluid to be kept in 
dark-coloured bottles). 
The objects were stained in toto for 24 hours, and afterwards acted 
on by a 1 per cent, alcoholic solution of bichromate of potash. This 
solution is made by mixing 10 parts of bichromate with 300 of distilled 
water, and then, when required, diluting 30 ccm. of it wdth 70 ccm. of 
strong spirit. This gives the proper colour after acting for 12 hours. If 
a lighter stain be desired, it must work for 24 hours. The objects are 
then transferred to 70 per cent, spirit, and kept in the dark for one or 
more .days. After this they are dehydrated in absolute alcohol, and 
Comptes Eendus Soc. Biol. Paris, 1889, No. 27; Centrabl. f. Bakteriol. u. 
Parasiteuk., vi. (1889) p. 519. 
t Arch. f. Mikr. Auat., xxxiii. (1889) pp. 125-52 (2 pis.). 
