316 ANIMAL LIFE 
Lagoon’: a pool or lake; the still water inclosed within an atoll. 
Lar'va: 57. 
Lépidép'terous : referring to the Lepidoptera, or moths and butterflies, 
Lit'toral: 160. j 
Lumen: the cavity of a tubular organ. 44, 
Medu'sa: 24, 
Még’alops: 59. 
Més’oderm: 20. 
Métab'olism: the act or process by which dead food is built up into 
living matter, and living matter is broken down into simpler prod- 
ucts within a cell or organism. 
Métamor' phosis: 56. 
Migra'tion: 70. 
Mil'limeter: about one twenty-fifth of an inch; a term used in the 
metric system of measure. 
Mimiicry: 112. 
Mind: 140, 
Molt: 57. 
Mbndg'amous: said of animals in which a male mates with only a 
single female. 
Multiplication: used in the text usually synonymously with repro- 
duction. 
Myrmeciph’ilous: said of insects which are found inhabiting the nests 
of ants. 
Natural selection: 70. 
NG'tochord: an elastic rod, or row of cells, formed in the early embryo 
of chordate animals (including all the vertebrates and some others), 
which lies below the dorsal nervous tube and above the ventral ali- 
mentary tube. 
Nu’cleus (pl. nuclei): 2. 
Cis3ph’agus: 42, 
Olfactory : referring to the sense of smell. 
Oma'sum: 42, 
Organ: 37. 
Organic: referring to the matter of which animals and plants are com- 
posed, 
Organism: a living being, plant or animal. 
Orienta'tion: 95, 
O'tolith: 121, 
