A FLAGELLATED HELIOZOAN. 
HOWARD CRAWLEY. 
Ix sore water taken from the pond in the Botanical Gardens 
at the University of Pennsylvania, in August, 1899, the two 
Heliozoa here figured were found. : 
Of these, that shown in Fig. 1 possessed a typical heliozoan 
body of foamy protoplasm. There was a clear, colorless outer 
layer, while the central portion consisted of an aggregation of 
small spherical bodies, greenish, reddish, and yellowish in color. 
The nucleus was invisible, and a contractile vacuole was not 
observed. 
The most striking feature of the animal was the pseudopodia. 
These were of two kinds. The longer closely resembled those 
of Actinophrys. They projected in a more or less radial direc- 
tion and showed considerable freedom of movement, frequently 
sweeping through large arcs. They always, however, preserved 
their straightness. At different times they varied greatly in 
length, and were often wholly withdrawn. i 
The shorter pseudopodia were extremely delicate strands of 
protoplasm that projected radially from the surface of the 
animal. The outer end of each of these was modified in such 
a way as to render it more conspicuous, but I was not able to 
determine the exact nature of this modification. In the speci- 
mens that were observed, the entire system moved in concert, 
the movement consisting in an alternate lengthening and 
shortening of the pseudopodia. Fig. 1 shows them at the 
greatest length that I observed. | In such cases the spherical 
body of the animal appeared as if inclosed by a definite ring. 
At other times these pseudopodia were wholly withdrawn. 
The animal was highly polymorphic, and occasionally, when 
all the pseudopodia of both kinds were drawn in, its shape 
departed so far from the spherical that it might have been 
taken for a sluggish Amoeba. 
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