CCXXVlll 
APPENDIX. 
Idotea Baffin!. 
I. linearis, antennis externis corpore longioribus dorso spinoso, caudse segmento ultimo elongate, 
apice subulate. 
Plate 1, fig. 4 — 6. 
Brought up by the trawl in considerable numbers from twenty fathoms 
depth, coarse sandy bottom, on the west coast of Baffin’s Bay, in latitude 71°. 
Exterior antennae usually about one-sixth longer than the body, of four 
tubular, cylindrical articulations, exclusive of a peduncle ; the second and 
third equal, and longer than the terminal, which is annulate. Inner antennae 
not larger than the peduncles of the exterior pair, of three filiform articulations 
on a compressed fleshy peduncle, (fig, 6 magnified.) Eyes reniform ; body 
linear, subcylindrical, of six segments exclusive of the head and tail, which 
last consists of two segments besides the terminal ; the third segment of the 
body is equal in size to the two on either side. Legs fourteen, five 
jointed ; first pair short, soft, compressed, ciliate beneath ; second, third, and 
fourth pairs similar, laterally compressed, with long ciliaB on the anterior 
edge, directed forward and increasing successively in size ; the second joint 
of these legs is much shorter than the others ; fifth, sixth, and seventh pairs 
similar, decreasing in size, stout, tubular, and cylindrical, terminated by a 
strong curved nail. Abdomen with a four-valved receptacle. Branchiae five 
pair, fleshy and ciliae, the two first with long peduncles ; covered by a strong 
and single plate, acuminate at the termination, and shut in by two longi- 
tudinal plates beneath ; these are channelled down the middle, attached by 
the exterior side, and unfold from their junction in the middle. The back 
is armed with a double row of strong spines, two on each segment, which 
are strongest towards the tail ; the back, tail, antennae and legs hirsute ; the 
females were observed to have their young attached to the exterior antennae. 
