PROTOZOA OR SIMPLEST ANIMALS. 
19 
Fig. 15. 
; polymorphus , the Trumpet Polypus (Fig. 11), has a funnel-shaped High Wall 
body of green colour, about of an inch in length, and is usually Case ^ f 
to be found singly or in groups attached by the narrow end to Gallery, 
duck-weed, sticks, &c. ; when swimming, the organism changes its 
shape considerably, becoming ovoid or 
pear-shaped. The cilia are uniformly 
distributed over the whole surface, but 
form a spiral fringe of long cilia round 
the anterior edge. See Plate XIIa., 2, 
in the Case. 
Paramecium aurelia , the Slipper 
Animalcule (Plate XIIa., 1, in the 
Case), has an oval flattened body with 
cilia uniformly distributed over the 
whole surface. Stylonychia (Fig. 15) 
has cilia only on the under surface of the 
flattened body; the thick spine-like organs 
are peculiarly modified cilia by means of 
which the organism can stalk about. 
Acinetaria. 
The body, in this group of Corticata, 
is provided with tentacle-like organs in 
place of cilia and flagella. Dendrosoma 
radians (Plate XIII. in the Case) is a 
fresh-water Infusorian of rather large 
size, attaining a height of ^ of an inch. 
A fixed stolon gives rise to branching Stylonychia myiau ^ the Mussel . 
Animalcule. Magnified 150 
diameters, a , mouth; b , con- 
tractile vacuole ; c, nucleus. 
trunks ; each branch terminates m 
numerous suctorial knobbed tentacles, 
which act by plunging into the bodies 
of their prey and sucking up the protoplasm. In the young stage, 
Dendrosoma is free and provided with cilia, which disappear when 
the animal becomes fixed. 
