LIST OF ILLUSTRATIONS. 
- Gradual transitions between Paludina neumayré (a), the 
oldest form, and Paludina hernesd (7)—from Neumayr . 
. Life history of Amaba 
. Actinophrys sol (Sun- animalcule)—after Grenacher 
. Polystonella, megalospheric form, with large central chamber 
(AZ) and one nucleus (4/)—after Lister 
Polystomella, microspheric form, with large central chamber 
(c.c.), numerous nuclei (), bridges of- protoplasm 
between chambers (8)—after Lister a ‘ 
. Paramecium—after Biitschli . 
. Conjugation of Paramecium aurelia — four stages—after 
Maupas . 
. Diagrammatic expression of process of conjugation i in Para- 
mectum aurelia—after Maupas . . 
. Vorticella—after Biitschli , . : ‘ 
. Volvox globator—after Cohn . i 3 . 
. Life history of MWonocystzs—after Biitschli a . 
. Life history of Gregarina—after Biitschli . . 
. End-to-end union of Gregarines—after Frenzel - 
. Life history of Coccidium—after Schaudinn. . . . 
. Diagram of Protomyxa aurantiaca—after Haeckel . . 
. Formation of shell in a simple Foraminifer—after Dreyer 
. A Foraminifer (Polystomel/a) showing shell and pseudopodia 
—after Schultze . 
. A pelagic Foraminifer—Hastigerina. (Globigerina) Murrayi 
after Brady 
. Optical section of a Radiolarian (Actinomma)—after Haeckel 
. Glossina palpalis, tse-tse fly ‘i 
. Trypanosoma gambiense 
. A colonial flagellate Infusorian—Proterospongia haechelii— 
after Saville Kent . 
. Simple sponge (Ascetta primoriialis)—afier F Haeckel ss 
. A sponge colony : 
. Sponge spicules 
. Section of a sponge—after FE. Schulze F 
. Diagram showing types of canal system—after Korschelt and 
Heider. The flagellate regions are dark throughout, the 
mesogloea is dotted, the arrows show the direction of the 
currents. All the figures represent cross-sections through 
the wall . : 
. Development of Sycandra raphanus—after F, E. Schulze 
. Diagrammatic representation of mag susan of Oscarella 
/obularis—after Heider . 
. A, Young ae i a Whitman. “RB, Female Orthonectid 
(Khopalura giardii)—after Julin . 
. Salinella—after Frenzel 
. Diagram of Ccelenterate structure, endoderm ‘darker through: 
out 
. Colony of Hydractinia on back of a Buccinum shell tenanted 
by a hermit-crab . ‘ . . : . 
