46 CAPRELLID. 
Caprella spinosa. Goopstr, Edin. Phil. Journ. xxxiii. pl. 3, 
f. 1-3. Wuure, Pop. Hist. Brit. Crus. p. 197. 
Protella phasma. Spence Bare, Cat. Amph. Brit. Mus. p. 351, 
pl. lv. fig. 4. 
Astacus phasma. Pennant, Brit. Zool. iv. p. 27, Hdit. 1812 
(descr. only). 
Tue head of this species is rounded in front, while a 
sharp, strong tooth, directed forwards as well as upwards, 
is situated upon the dorsal surface of the posterior mar- 
gin just where the head is contiguous with the first joint 
of the body, from which it can scarcely be identified. 
The first joint of the body is likewise furnished with a 
similarly strong, sharp-pointed tooth, situated near its 
posterior margin. The second segment carries near the 
centre a pair of strong teeth, one on each side of the 
dorsal median line, as well as a third, situated in the 
middle of the dorsal surface, near the posterior margin. 
The third and fourth segments exhibit rudimentary pro- 
cesses, probably representing teeth in similar positions. 
The superior antenne are rather more than half the 
length of the animal. The inferior antennz are about 
half the length of the superior. The first pair of legs 
are short; the hand triangular; the palm defined by a 
sharp process. The second pair are very much longer; 
the hand is large, elongate-ovate, the palm having a deep 
excavation near the anterior extremity, and defined by a 
prominent blunt tooth, surmounted by one or more 
spines. The finger articulates with the hand somewhat 
before the apex, so that a sharp process is produced 
above and beyond the articulation. The three posterior 
pairs of legs have the hands arcuate, the anterior margin 
being armed with small tubercles, surmounted by a spine, 
and defined by a strong process, which is surmounted by 
several short spines directed towards the extremity, and 
