PROTOZOA OR SIMPLEST ANIMALS. 
11 
coloured with crimson, blue and yellow tints, and have been well High Wall 
termed “ gems of the ocean.” Their skeletons assume an endless ^ as ® nd of 
variety of beautiful and curious shapes, such as spiny latticed Gallery, 
spheres, rings, beehives, &c. The Radiolaria, of which about 
4,000 species have been described, are primarily classified according 
to the structure of the central capsule, the shape of the skeleton 
tending to conform, more or less, to the shape of the latter. 
Professor Haeckel divides the group into four Orders : — 
Fig. 8. 1 
Haliomma wyvillei. Magnified 200 diameters. (After Wyville Thomson.) 
I. Spumellaria (Fig. 8), and see Plate VII. and Models 9-12 
in the Case, with spherical central capsule uniformly perforated by 
pores. Here the skeleton is typically formed of a latticed sphere or 
of several concentric latticed spheres united by radial beams which 
do not penetrate the central capsule, and with radiate spines. 
From “The Voyage of the Challenger — Atlantic.” 
