404 The Botanical Gazette. [December, 
such constancy on laboratory cultures of horse dung that it 
seems hardly possible it should have escaped previous descrip- 
tion as a chromogenous coccus. The only form which has 
been described on this substratum to which it could possibly 
be referred is Micrococcus fulvus Cohn’. This species appears 
however, to be a true Micrococcus and, judging from the spec- 
imen in Rabh. Alg. Eu. no. 2501, bears little resemblance to 
the present form. The drop-like masses are at first more or 
less coherent and may be transferred intact to a slide for ex- 
amination; but they soon become deliq t, adjacent guttul 
coalescing into viscous masses more than a millimeter in diam- 
eter. The variation from flesh-color to orange-red forms 
may indicate an additional species, the orange type retaining 
this tint in agar cultures without varying towards the flesh- 
colored form. The morphological differences if there are any, 
are, however, too slight to warrant a specific distinction. 
Myxocoecus virescens n. sp.—Rod masses greenish yellow. 
Rods as in M. rubescens. Spore masses clear yellow-green 
rather smaller spore masses. When cultivated on potato 
agar it tends to lose its green color and become yellowish. 
The spores seem constantly larger than in the preceding 
species. | 
Myxococeus coralloides n. sp.-—Plate XXIV, figs. 29-33-— 
Rod masses pale pinkish, thin. Rods slender, curved, 4—7 
X.4#. Spore mass firmly coherent, ereet, variously branched 
or lobed, the lobes or branches usually tapering towards the 
rounded apex, flesh-colored, becoming bright pinkish when 
dry; maximum height 350y, the lobes about 20-30/ in diam- 
eter. Spores spherical, 1-1.2 in diam. 
On decaying lichens, Cambridge, Mass. 
This striking form made its appearance in laboratory cul- 
tures and was readily cultivated on lichens and potato agar. 
The coral-like form of the spore mass is very variable, pre 
senting every imaginable variation from a simple papilla toa 
complicated structure similar to that represented in fig. 29. 
In addition to the species above enumerated the writer has 
observed several others, among them a very minute and peculiar 
*Cohn: Beitr. z. Biol. d. Pflan. 1, 3, p. 181. 
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