312 
MAYNARD M. METCALF 
dia were generally rather active, the Amoebae moving about with 
sufficient rapidity to render camera drawing a little difficult. 
Upon the rounded portion of the body in these Amoebae, one 
observed, in different individuals, from six to thirty globular pro- 
tuberances C^gemmules") each containing from eight to a dozen 
or fifteen little highly refractive spherules, doubtless nutritive 
plastids similar to those so common in Foraminifera, Flagellata 
and Cihata. 
With the aid of some of my students, individual Amoebae of this 
sort were kept under continuous observation, once for forty-eight 
hours, and three times for a period of thirty-six hours, while other 
individuals were observed at intervals of a few hours, each one for 
more than a week at a time. No gemmule was ever see o to de- 
tach itself from an Amoeba. On the other hand many Amoebae 
were found, from which gemmules had recently been set free. 
Many of these Amoebae were wholly or partially surrouuded by 
a thick degenerated or degenerating cyst, while others showed 
no trace of an enveloping cyst. From the fact that so many 
hundreds of thousands of these Amoebae were seen with the freed 
gemmules still lying near them, it is evident that the gemmules, 
after being freed, often, if not always, remain inactive for a con- 
siderable time. 
All through the liquid were countless millions of biflagellated 
organisms (Cercomonads) of the same type as the gemmules at- 
tached to the Amoebae, as just described, and showing :he same 
highly refractive plastids within them (figs. 35 a-h). Often also 
a minute contractile vacuole was visible. These Cercomonads 
swim but slowly by feeble movements of the flagella. Frequen tly 
one sees them draw in their flagella and become amoeboid. 
Again, after a time, they may resume the flagellate condicion, often 
one flagellum (the anterior one) forming before the other. Some- 
times some of these amoeboid individuals attach themselves to 
the cover glass, flattening out upon it and showing grotesque 
shapes as they crawl slowly about (fig. 37 a-f). The resemblance 
of these amoeboid and biflagellate forms to the gemmules already 
1^ All the figures given are from camera drawings. 
