HOMOLOGIES AMONG CRUSTACEA. 
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VOCABULARY. 
Anal’o gous (Gr. axa, according 
to, and /ogos.) Analogous organs 
are those having the same use 
but not necessarily the same 
structure or origin. 
Bas ip’o dite (Lat. daszs, base, and 
Gr. fous, foot), part of a crus- 
tacean appendage. 
Car’a pace (Lat. capara, a hood), 
the hard covering of the cephalo- 
thorax in crustacea. 
Cephaliza'tion (Gr. ephale, 
head), a tendency to aggregate 
nerves and organs of sense near 
the head. 
Cox op’o dite (Lat. coxa, hip, and 
Gr. fous), the joint of a crusta- 
cean appendage nearest the body. 
Crus ta’ce a, a class of arthropoda 
commonly having a hard shell. 
Dec’a pod (Gr. deka, ten, and gous), 
an order of crustacea having ten 
legs. 
Dif fer en tia’tion (Lat. ds,apart, 
and fero, to carry), the setting 
apart of tissues and organs to 
perform special kinds of work. 
Em bry ol’o gy (Gr. embryon, an 
embryo, and Zogos), the study of 
embryonic life. 
En dop’o dite (Gr. ez, in, and ozs), 
the outer branch of a swim- 
meret. 
Ex u'vi um (Lat. exzo, to strip off), 
the cast-off skin of an insect or 
crustacean. 
Fang, a hollow tooth emitting 
poison. 
Fer til i za’tion (Lat. fro, to bear), 
the union of male and female 
cells to produce living seeds or 
eggs. 
Gill, an organ for breathing the 
oxygen dissolved in water. 
Ho mol’o gous (Gr. omos, same, 
and /ogos), having the same rel- 
ative position and structure. 
T’so pod (Gr. sos, equal, and fous), 
an order of crustacea having the 
legs of equal length. 
Max il/li ped (maxz//a, and fous), 
a foot-jaw. 
Os mo’sis (Gr. osmose, pushing), 
an interchange of gases or 
liquids through a slightly porous 
substance. 
Pro top’o dite (Gr. protos, first, 
and fous), a part of a swimmeret 
consisting of the basipodite and 
coxopodite. 
Re’nal (Lat. renalis, kidney), per- 
taining to the kidneys. 
Ros‘trum (Lat. rostrum, a beak), 
a weapon of defence on the front 
of the carapace of a crustacean. 
Sed’entary (Lat. sedeo, to sit), 
inactive. 
Ses’sile (Lat. sedeo, to sit), joint- 
ed to the body without stems or 
stalks. 
So’mite (Gr. soma, a body), a 
segment of the body of one of 
the arthropoda. 
Swim mer et’, a jointed appendage 
on the abdomen of a crustacean. 
Tac’tile (Lat. ¢ango, to touch), 
having the sense of touch. 
Tel’son (Gr. ¢e/son, a boundary), 
the posterior somite of a crus- 
tacean. 
Tet ra dec’a pod (Gr. Zetra, four, 
deka and pous), an order of 
crustacea having fourteen legs. 
