TERMS USED IN DESCRIBING CRUSTACEA 
Abdomen: The posterior part of the body. 
Antenne: Articulated appendages which immediately precede 
the mouth. 
Anten’nules: The anterior of the two pairs of feelers of the head. 
Bira’mous: Having two branches. 
Carapace: A thin chitinous shell covering the cephalothorax. 
Cephalic: Pertaining to the head. 
Cephalotho’rax: The united head and thorax. 
Chela: The pair of pincers, or claw, which terminates some of 
the appendages. 
“Che'liped: A leg with chela, or claw, at the end. 
Endop’odite: The inner one of the two main divisions of the 
limb. 
Epime’ra: Divisions on the ends of the segments of amphi- 
pods and isopods, and belonging to the legs. 
Epip’odite: A third branch of a limb. 
Epis'toma: A triangular area in front of the mouth. 
Exop’odite: The outer one of the two main branches into 
which the typical limb of any segment is divided. 
Gastric mill: The first halfof the stomach, where food is ground. 
Mandibles: The pair of appendages next behind the antenner. 
Maxil'le: The first pair of appendages after the mandibles. 
Mawxillipeds: The three pairs of appendages after the maxille. 
Metame’res : Segments. 
Orbits: Hye-cavities, peculiar to the higher Crustacea. 
Prosto'mium: The region in front of the mouth; the preoral 
part of the head. 
Rostrum: The beak in front of the head. 
Segment: A part cut off or marked as separate from others. 
Somite: A segment of the body. 
Squame: A scale. 
Telson: The last segment of the abdomen. 
Thorax: The middle part of the body. 
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