188 THE AMERICAN MONTHLY | [July 
12 The plague bacillus is destroyed by sulphur fumi- 
gation and by formaldehyde gas in the strengths in which 
these disinfectants are usually employed. The gases can 
only be depended upon as surface disinfectants. In dis+ 
infecting ships, warehouses, dwellings, and other places 
infested with rats, fleas, and vermin, sulphur is better 
than formaldehyde, because sh esionnts cos gas fails to one 
. the higher forms of animal life. 
13 A temperature of 70° C. continued a shokt time is 
invariably fatal for the plague bacillus. The ordinary an- 
tiseptics are all efficacious in their usual strength for 
non-spore-bearing organisms. Efficient surface disinfec- 
tion may be accomplished by exposing objects all day to 
the direct sunshine on warm days. The temperature in 
the sun must be above 30° C. 
Work on Ciliate Infusoria. 
In a recent bulletin of the California Academy of Sci- 
ences, N. M. Stevens has described two new Infusorial 
forms. During his studies he worked on them microscopi- 
cally and writes, in part, as follows: 
Technique.—The respiratory tree was removed from the 
living holothurian, plunged into the fixing fluid, and later 
washed, and hardened in alcohol. Small pieces were im- 
bedded in paraffine in the usual way, and sections 5 to 7 
microns thick were cut and mounted in series. For in toto 
preparations, portions of the respiratory tree were stained 
washed, and run into glycerine or through alcohols, fol- 
lowed by clove oil, teased upon the slide to free the infu- 
soria from the respiratory membrane, and mounted in 
glycerine, glycerine jelly, or balsam. 
A large number of fixing agents were tried: picro-ace- 
tic, picro-sublimate-acetic, Gilson’s fluid, sublimate-ace- 
tic, iridium chloride-acetic, Flemming’s strong and weak 
solutions, Vom Rath’s solution, platinum chloride-acetic, 
Hermann’s fluid, absolute alcohol, absolute-acetic, palla- 
