ANIMAL ACTIVITIES. 
138 
1. Habitat. 
2. Mode of Locomotion. 
3. Mode of Breathing. 
4. Kind of Food Used. 
5. Classification. 
Topics for Reports. The Portuguese Man-of-war. 
Sea-anemones. Coral Islands. The Origin of Atolls. 
Coral Reefs. How Corals Have Helped to Build 
Florida. The Origin of Plants and Animals on Coral 
Islands. Examples of Alternation of Generation. 
Commensalism. Colonies. Experiences while Col¬ 
lecting Ccelenterates. Parasitism. Symbiosis. 
VOCABULARY. 
Cam pan u la'ri an (Lat. dim. of 
campana, a bell), a kind of hy- 
droid whose feeding zooids live 
in a bell-shaped case. 
Com.men'sal ism (Lat. cum , to¬ 
gether, and mensa, a table), a 
state of living together for mutu¬ 
al advantage, as in the case of the 
hermit-crab and hydractinia. 
Her maph'ro dite (Gr. Hermaphro- 
ditos , the son of Hermes and 
Aphrodite), having both male 
and female reproductive cells in 
the same animal. 
Hy'dranth (Gr. hydor , water), one 
of the nutritine zooids of a hy- 
droid colony. 
Hy'po stome (Gr. hypo, under, and 
stoma , a mouth), the part of a 
hydroid animai bearing the 
mouth at its summit. 
Las'so cell (Lat. laqueus , a snare), 
a sensitive nettling-cell contain¬ 
ing a coiled thread. 
Me du'sa (Lat. Medusa, one of the 
Gorgons), an umbrella-shaped, 
free-swimming jelly-fish. 
Mes'en te ry (Gr. mesos , middle, 
and enteron , intestine), one of 
the radiating walls in the body 
of a polyp. 
O'vum (Lat. ovum), an egg. 
Pol'yp (Gr .polys, many, and/owj, 
foot), a feeding zooid of a hy¬ 
droid or coral-forming colony. 
Sep'tum (Lat. septum, a fence), a 
radiating portion of a coral skel¬ 
eton. 
Ten'ta clc (Lat. tento , to try to 
hold), a feeler around the mouth 
of a coelenterate. 
The'ca (Gr. theke , a case), a 
portion of a coral skeleton. 
Zo'oid (Gr. zoon, an animal, and 
oid, like), one of the members of 
a coelenterate colony. 
