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Scientific Memoirs by
presenting uniform and quite distinctive peculiarities ; forming a comparatively thick stra-
tum of a warm Indian yellow colour surrounded by a halo of neutral tinted discolouration of
the surface of the medium ; odourless ; surface dryish and very conspicuously nodulated
as though composed of masses of confluent colonies ; elements consisting of short, thick
commas very similiar to those present in most growths occurring in neutralised agar-agar
media. (Plate IV, Figs. 10, a . and b.)
5. Growth in bouillon.—Presenting no characteristically distinctive features where
the medium has been neutralised, and entirely absent in cases where it has not been so.
Form v .
1. Growth in neutralised agar-agar media. —Occurring rapidly both superficially and
interstitially ; superficially forming a thick layer almost invariably of highly adhesive or
ropey consistence ; elements somewhat variable in form ; but ordinarily short and fairly
well-curved.
2. Growth in non-neutralised agar-agar media. —Uncertain ; in some cases as much
retarded and abortive as those of forms ζ o r
θ a n d t h e n c o m p o s e d o f c o c c o i d e l e m e n t s , b u t
in others occurring with fair rapidity and consisting of elements resembling those in cul-
tivations in neutralised media.
3. Growth in common nutrient gelatine.—Liquefaction occurring rapidly, especially
latterly, so that complete solution of the medium occurs sooner than it does in cultiva-
tions of any of the other forms except α and ι. (Plate I, Fig. 6, b . Plate III, b, Figs. v.)
4. Growth in potatoes. —Has never been obtained in spite of numerous attempted
cultivations.
5. Growth in bouillon. —Showing no distinctive peculiarities ; entirely absent where the
medium is not neutralised.
Form ξ.
1. Growth in neutralised agar-agar media. —Occurring rapidly both superficially and
interstitially ; superficial growth almost always tenacious or ropey ; elements almost always
characterised by small size and very defective curvature.
2. Growth in non-neutralised agar-agar media. —Occurring relatively rapidly, but
confined solely to the surface of the medium ; elements consisting of very short rods, many
of them clearly formed of paired cocci, the majority straight, but a certain number more or
less curved ; only a very few retaining the characters of typical commas.
3. Growth in common nutrient gelatine.—Liquefaction occurring comparatively
slowly ; channel of liquefaction conspicuous from the opacity of its walls and containing a
considerable amount of deposit. (Plate I, Fig. 7, a . Plate III, b, Figs. ξ . )
4. Growth in potatoes. —Primarily occurring readily and freely, but entirely abortive
after prolonged cultivation in agar-agar media ; when free, giving rise to the formation of
thick, bright-pink expansions with a dryish and somewhat irregular surface ; surrounding
surface of the substratum at first of a conspicuous neutral tint, passing on gradually into
a dull brown ; almost entirely odourless ; elements in most cases presenting the character of
those in cultivations on non-neutralised agar-agar media, but occasionally taking the form
of elongated curved rods of considerable size. (Plate IV, Fig. 11, a and b .)
5. Growth in bouillon. —Showing no distinctive peculiarities ; entirely absent where
the medium is not neutralised.