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to ramify more, and already to form an anastomosis here and 
there. 
After nourishment had been taken, vacuoli first began to 
appear in the Amoeba, but these were entirely absent both in 
the stationary and in the swarming spores. Generally there 
appeared first a single vacuolum, less frequently two or three 
together, like bright, slowly pulsating, circular spots in the 
reddish-yellow Amoeba-body. But it could be already estab- 
lished, by continuous observation, that the vacuoli were not 
constant retractile vesicles, but were accumulations of fluid 
within the contractile homogeneous plasma-parenchyma. 
They sometimes appeared in one place, sometimes in another, 
without reappearing after they had vanished. I could many 
times immediately follow in the swarms of Protomyxa under 
my eyes the formation of a plasmodium by the growing 
together (concrescence) of two or more Amoebae. Some- 
times it happened that two Amoebae, which had left a Navicula 
free at the opposite ends, and had drawn themselves over it, 
by meeting in the middle, flowed together into one (figs. 8, 9). 
After the subsequent digestion the united plasma-mass with- 
drew itself, like a single Amoeba-like individual, from the 
empty siliceous shell. But in the free Amoebae also, which 
met upon the glass and touched with their outstretched 
pseudopods, the process of union could be immediately 
observed. There, when the Amoebae crept near and among 
each other in thick groups on the surface of the glass, I often 
saw three or four unite together at once (fig. 7) . Thus origi- 
nated larger plasmodia, which already showed a transition to 
the above-described full-grown Protomyxa (fig. 10), from 
their larger number of vacuoli, and from the more numerous 
ramifications and anastomoses of the extended processes. 
Whether the formation of a plasmodium, i.e. the origination 
of larger sarcode bodies by concrescence of several Amcebse, is 
a necessary and inseparable process in the development of 
the growing Protomyxa, or a mere accidental and indifferent 
one, I am unable to decide. But I think the latter case is 
more probable. I isolated several simple Amoebae singly in 
small glasses, and furnished them with plenty of diatoma- 
ceous nourishment. In a few days they became perceptibly 
larger, and attained from four to six times their original 
volumes. The pseudopods became longer, and formed more 
numerous branches and anastomoses. There is no reason for 
presuming that none of the above-mentioned Amoebae, by such 
continuous growth, could reach the full size of the completely 
developed Protomyxa, and could then reproduce itself just as 
well, and in the same manner, by sporogony as the plasmodia. 
