264 BOTANICAL GAZETTE [ OCTOBER 
in diameter and becomes more deeply colored, sometimes show- 
ing a slight zoning, the deeper pink in the center. The only 
evidence of liquefaction at first is that the surface of the gelatine 
sinks perhaps more rapidly than could be accounted for by 
ordinary evaporation, forming a hollow cup-shaped cavity lined 
by the smooth dry pink layer of the expanded 
surface colony. If the gelatine is rather stiff 
this surface sinking takes place very slowly. 
This dry cavity may reach two or three centi- 
meters in depth in the course of a month 
(fig. 2). The deep growth along the needle 
track remains colorless and little developed. 
oe Agar.—To the eye the agar plate colonies ue 
do not differ materially from those on gelatine. hae 
They appear on the fourth day at room temper- 
rature as minute dots, which take on a yellowish tinge. 
ined under low power they are seen to be very irregular, and 
unlike the gelatine colonies they do not become smooth edged 
and round upon reaching the surface, but retain their irregue 
larity, the edges showing a slight raggedness. The texture 1s 
uniform and very finely granulated, being somewhat more dense 
in the center and thinner on the periphery. They become sal- 
mon-pink in the course of a few days and increase very slowly 
in size (fig. 3). 
Agar streak shows beginning of development in twenty 
Fie, 7. 
Exam- 
-four 
hours as a slight whitish growth along the needle track. In 
forty-eight hours it has become 4 ar 
pink, a much more creamy OF yellowis J 
pink than the rose culture of M. fs 
of a day or two older but of about t 
Fic. 3. same development. Later the ie 
becomes quite luxuriant, gra . 
deepening in tint. It has much the same appearance 
the agar growth of a pink yeast, Torula III, except perhaps 
for a more decided salmon color. On fresh, moist agar 
edges are.smooth and the whole growth a straight, shining: 
