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MRS. G. C. FRANKLAND AND DR. P. F FRANKLAND 
decidedly less rapid; whilst B. Icevis possesses the power of liquefying gelatine to a 
much less extent than either of the other two. 
Agar-agar cultivations. — B. snbtilis is very sharply distinguishable from the other 
two by the property wdffch it possesses of imparting a characteristic wrinkled 
appearance to the surface of the agar-agar. 
Colonies on gelatine plates .—The colonies produced by B. Icevis are, as has been 
shown above, very different from those of the other two, whilst we have not been 
able to establish any substantial difference between the colonies of snbtilis and cereus 
beyond the difference in the rate of liquefaction, already referred to, and the longer 
and more spiral form of the whip-like extensions which we have constantly observed 
to be characteristic of B. cereus. 
Microscopic appearance .—In this respect, again, B. Icevis exhibits a marked 
difference from the other two, its dimensions being very decidedly smaller. 
12. Bacillus (Micrococcus) Prodigiosus. 
This organism was first described by Cohn as a micrococcus, but is now generally 
regarded as a bacillus. 
We have met with this organism both in air and water, but w r e have especially 
studied it from a cultivation obtained by one of us from Dr. Koch’s laboratory in 
Berlin. 
Microscopic appearance. —The cells are rather longer than broad, the largest forms 
being about 1'7/r in length and about 1/x in width ; they are frequently found 
hanging together in pairs. More distinctly bacillar forms have been described by 
Cornil and Babes (‘ Les Bacteries,’ 1886, p. 141) as occurring in broth-cultivations. 
We can fully confirm these observations, having ourselves seen them in drop- 
cultivations, and, what is more convincing,in single colonies. (See Plate 20, fig. l,No. lc.) 
Appearance in Cultivations. 
Gelatine. —Grows very rapidly, liquefying the gelatine in the form of a conical sack 
(see Plate 20, No. 16) which soon extends across the tube at the top and, gradually 
passing downwards, involves the whole tube. The liquid formed is very turbid, with 
an abundant flocculent deposit of an intensely crimson colour. Near the surface there 
is generally seen adhering to the glass a thin layer of still darker red colouring 
matter which has the peculiar fluorescence of an aniline colour when in a concen¬ 
trated state. 
Agar-agar. —Grows very rapidly over the surface, producing a deep, blood-red, 
smooth and shining expansion, the colour being only developed on the surface. (See 
Plate 20, No. la.) 
Broth. —Grows rapidly, rendering the broth turbid, and producing in the first 
