OLIVE : MONOGRAPH OF THE ACRASIEAE. 
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these amoebae that Cienkowsky examined, he noted one especially 
which was easily distinguished by the presence of two nuclei con¬ 
nected with each other. This double nucleus is also a feature which 
Dangeard observed in Sappinia and he regarded it as a stage of 
nuclear division. Many of the individuals of the American forms 
showed the same peculiarity even in the resting encysted condition, 
but I was not able to decide whether they were concerned with the 
phenomena of nuclear division. Gruber has, in fact, described a 
species. Amoeba hinucleata, which normally possesses a double 
nucleus, so that the conditions in Sappinia may be of a similar 
nature. 
It is, moreover, not impossible that in the union of numerous 
individuals of Amoeba verrucosa into a common aggregation, 
described by Rhumbler (’ 98 ), we have a phenomenon similar to the 
aggregation in Sappinia. It is suggested by Calkins, however, 
(tOl, p. 218) that the phenomenon in the case of Amoeba verrucosa 
may be the result of the production of numerous swarm spores, as 
in Paramoeba. 
Guttulinaceae. 
Myxamoebae either Umax shaped, without pseudopodia, or of 
the ordinary form with rounded or lobose short pseudopodia. Sori, 
irregular in shape or spherical, sessile or stalked, consisting either 
of spores, which possess a definite wall of cellulose or similar sub¬ 
stance, or of pseudospores, which are simply encysted individuals 
without definite walls. 
Guttulinopsis Olive, 1901. 
Plate 5, fig. 8-22, 25, 26. 
Proc. Amer. acad. arts and sci., vol. 37, p. 335, 1901. 
Myxamoebae having lobose pseudopodia. Sori sessile or stalked, 
composed of pseudospores, those of the stalk usually slightly 
elongated. 
Guttulinopsis vulgaris Olive. Plate 5, fig. 8-19. 
Proc. Amer. acad. arts and sci., vol. 37, p. 336, 1901. 
Sori usually stalked, sometimes sessile, about 150 /u,-500 /u, in 
