PROTOZOA OR SIMPLEST ANIMALS. 
15 
Flagellata. 
The Flagellata are Corticata in which the cell-body is provided High Wall 
with one or a few flagella. The cell may be solitary (Fig. 11a), or ^, as ® nd of 
may be joined with others to form colonies (Figs. 11b, c). Gallery. 
Fig. 11. 
Flagellata. a. Cercomonas crcissicauda, a one-celled Flagellate (x 400). 
b. Gonium pectorale (X 325). c. Volvox globator with daughter and grand- 
daughter colonies ( x 55). (After Carter.) d. Surface view of Volvox 
showing cells in hexagonal spaces in common jelly ; n, nucleus ; cv, con- 
tractile vacuole. Very highly magnified. (After Butschli.) e. Vertical 
section of wall of Volvox ( x 800). a, pairs of flagella. (After Cohn.) 
Volvox glolator (Figs. 11c, d, e), and Plate IXa. in the Case, occurs 
at times in great abundance in ponds, even to the extent of giving a 
green colour to the water. The little organism, which is about of 
an inch in diameter, looks like a tiny green speck moving about in 
