OLIVE : MONOGRAPH OF THE ACRASIEAE. 
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ground that “the myxamoebae undergo no differentiation into stalk 
and head cells, whereas in Cienkowsky’s form, there is a slight dif¬ 
ferentiation.’’ The fact that certain species of Guttulinopsis show 
both stalked and sessile forms in the same culture diminishes the 
importance of the stalk as a character of generic value and justifies 
the resumption of the original name given by Fayod. 
G-uttulina aurea van Tieghem. 
Bull, de la soc. bot. de France, t. 27, p. 317, 1880. 
“ Guttulina aurea has its fruit pedicelled and resembles closely 
6r. rosea, but differs in color. Spores spherical, 4 /x-6 jx, golden 
yellow. Upon dung of horse.” France. 
Guttulina sessilis van Tieghem. 
Bull, de la soc. bot. de France, t. 27, p. 317, 1880. 
“ Fruit sessile; a simple droplet of pure white, resting directly on 
the substratum. Spores oval, colorless, aggregated in a sphere 
and cemented, as in the preceding species, by a gelatinous substance, 
4 p, X 8 fx. On the integument of beans in a state of decay.” France. 
Guttulina aurea and G. sessilis are known only from the original 
descriptions above quoted. Should it prove that these two forms 
possess pseudospores instead of spores, they should then be trans¬ 
ferred to Guttulinopsis. 
A form found on skunk dung by Dr. Thaxter (pi. 5, fig. 23- 
24) possesses oval, colorless, resting bodies of approximately the 
same size as those of Guttulina sessilis. Lack of figures and of 
other sufiicient information concerning van Tieghem’s species pre¬ 
vents, however, any certainty as to the relationships of the two 
organisms. 
Dictyosteliaceae Rostafinski. 
Myxamoebae possessing slender elongated pseudopodia. Sori 
consisting of spherical masses of spores or of a chain of spores ; 
stalked, the stalks composed of distinct parenchyma-like cells with 
cellulose walls. 
