ORDER L@MIPODA — CAPRELLA. 41 
GENUS CAPRELLA. Lamarck. 
Body linear or filiform, composed of unequal segments. The upper antenne with the last 
segment many-jointed, and as long as the three others. Two sessile compound eyes. 
Feet ten, elongated, arranged by pairs in an interrupted series, unguiculated ; the second 
and third segments furnished with branchial vesicles. Marine. 
CaPRELLA GEOMETRICA. 
C. geometrica. Say, Journ. Acad. Nat. Sciences, Vol. 1, p. 390. 
Description. Body smooth above. Head obtuse, with a short spine in front; three last 
segments of the body shorter, convex above; terminal one smallest, and truncate at the 
tip. Second pair of feet with dilated oval compressed hands armed with teeth; one of 
which is near the base, linear, and almost parallel with the palm; the other large, obtuse, 
little elevated, placed near the base of the claw: thumb curved, attenuated at the tip, where 
it closes on the posterior tooth. Branchial vesicles short, oval. Terminal pair of feet 
longest. 
Color. Body with a few scattering reddish brown spots; eyes red; antenne and feet 
annulate with reddish brown. 
Length, 0°3. 
This species is found among sponges and seaweed along the coast, on which it walks after 
the manner of some caterpillars called Measuring worms. It swims by alternate curvatures 
of the body. Dr. Gould has indicated two species on the coast of Massachusetts, which are 
very probably distinct from any hitherto described. 
(EXTRA-LIMITAL.) 
C. 
(Goutp, Mass. Rep. p. 335.) Delicate, without any spines on any part. Color, thickly 
dotted on the back with dark green. Length, 0°5. Massachusetts. 
C. sanguinea. (Iv. Ib. p. 335.) Head blunt. Lower antenne ciliated, and extending to the second 
segment, and the upper ones to the third segment: a spine on the middle of the first seement. Two 
last segments short and heart-shaped. Color, bright crimson. Length, 1°0. Coast of Massa- 
chusetts. 
C. equilibra. (Say, |. c. Vol. 1, p. 391.) First and second segments of the body equal to one half of 
the whole length. Second pair of feet placed in the middle of the body. Hand toothless: nail 
closing without an interval. Second pair very large; the hand oblong-oval; palm rectilinear, 
bidentate. Length, 1:0. Souwth-Carolina. 
Fauna — Parr 6*. 6 
