High Wall 
Case 
E. end of 
Gallery. 
14 GUIDE TO THE CORAL GALLERY. 
Eucecryphalus schultzei has only two segments, the lower being 
expanded out, and the central capsule is lobed ; see Model 16 in Case. 
IV. Phaeodaria (Models 17, 18), with a double-walled central 
capsule with a few large orifices, and surrounded by dark brown 
pigment. The skeleton of Aulosphmra (Model 17) is formed entirely 
of tubes of silex, which join to form a spherical lattice with triangular 
meshes, a tube with verticils of spines radiating from each node. 
This species, which lives at the surface in the Mediterranean, has a 
large shell of an inch in diameter. 
Aulcicantha (Model 18) has a skeleton formed of hollow siliceous 
tubes of two kinds, viz., radiating spines and loose needles arranged 
tangentially on the surface. 
CORTICATA OR INFUSORIA. 
If any animal or vegetable substance be allowed to remain in a 
vessel of clear water exposed to the air, in a short time tiny specks 
will be seen swimming about. The organisms appearing in these 
infusions were termed Infusoria or Infusions Animalcules. The 
organic matter has simply served as nutriment to the germs of 
these Animalcules previously existing in the water or in the air. 
Infusoria abound in fresh and stagnant water and also in the sea. 
The organisms grouped under this name differ from the Gymno- 
myxa, in having, in their adult phase, a dense cortical body-layer and 
often flagella or cilia in place of pseudopods. A cilium is a hair-like 
organ which can only bend and straighten itself, and which only 
acts in unison with other cilia. A flagellum acts independently, and 
with a lashing to and fro movement. 
The Oorticata may be roughly divided into four groups : Sporo- 
zoa, Flagellata, Ciliata, and Acinetaria. 
Sporozoa. 
The Sporozoa are parasitic Protozoa which live in the tissue-cells 
and fluids of other animals. The study of these organisms has of late 
years acquired an immense importance on account of the wide-spread 
and dangerous maladies to which some of them give rise in man, 
domestic animals, fishes, &c. For instance— to mention a few of the 
more important diseases — the various kinds of malaria in man, Texas 
fever in cattle, coccidiosis in rabbits and other animals, “ psorosperm ” 
disease (myxosporidiosis) in fishes, silkworm disease, and sarcospori- 
diosis in cattle, are all due to the presence of Sporozoa in the blood 
