316 
MAYNARD M. METCALF 
and that this Ufe cycle is a complicated one. The phenomena 
observed by Calkins cannot be properly judged without further 
study. 
B. Amoeba sp. (?) 
In the same aquaria in which were found the Amoebae described 
in section A of this part of this paper, and also in other foul 
aquaria stocked from other localities, one sees very numerous 
Amoebae of a different species (figs. 43 and 44), which also have 
external gemmules. They are smaller than the forms just de- 
scribed, and have much smaller gemmules, each containing but 
a single refractive spherule. Most of these gemmulating Amoebae 
are encysted, but some are found with no surrounding cyst. The 
gemmules when freed give rise to excessively minute Amoebae 
with no marked pseudopodia, resembling in form short and stocky 
A. limax. Further description and discussion will be reserved 
for a future paper. The gemmulating Amoebae of this smaller 
sort somewhat resemble individuals described by Penard^^ as A. 
radiosa var. gemmifera and their manner of reproduction is 
similar to that discribed by Mercier for Amoeba blartae.^'' 
C. A European Amoeba with reticulate Amoebospores 
In Wiirzburg I found gemmulating Amoebae in the surface 
scum of foul aquaria, stocked from the ponds in the garden of the 
Zoological Institute. Neither these Amoebae nor their gemmules 
contained refractive plastids. The gemmules, when freed, first 
became Amoeboid, but soon developed very long ani exceedingly 
delicate reticulate pseudopodia, whose branches were so fine as to 
be on the very border of visability with a Zeiss 2 mm. apochro- 
matic objective and illumination from a gas mantel (fig. 45). 
These reticulate amoebospores unite into groups of from two to 
five by means of their branchiag pseudopodia, but true copula- 
tion was not observed. 1^ 
" Notice sur les Rhizopodes der Spitzburg, in Archiv f. Protistenkunde, Bd. 
ii, 1903, see p. 245. 
i« Le cycle evolutif d'Amoeba blattae Biitschli, Archiv f. Protistenkunde, Bd. 
16, 1909. 
17 These were studied only a few times and but few hours at a time. My failure 
to observe copulation is therefore no indication that it does not occur. 
