8 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 
bears a stout process (pro) which terminates in two teeth and a ser¬ 
rate plate, homologous with the teeth and plate of the other man¬ 
dible. A palpus rudiment (p') is present in the fifth stage. The 
paragnaths (p) resemble their corresponding mandibles in that they 
are respectively tapering and conical. 
The remaining appendages are symmetrical in all stages. The 
eyes (pi. 2, fig. 25) are rather immobile and their shape recalls the 
eyes of Pagurid zoeae. The antennulae are uniramous in the first 
stage and on the inner surface near the apex is a long, feathered 
bristle. The inner ramus is developed at this point with the second 
stage, carrying the bristle upon its tip. This ramus becomes naked 
and is without joints in the later stage’s, and is longer than the outer 
ramus from the third stage on. The outer ramus becomes two- or 
three-jointed with the fourth, and five-jointed with the fifth stage. 
There are seven apical bristles in the first stage, four in the second, 
and two in the fourth. In the fifth stage the apex is naked. The 
penultimate joint in the fourth and all the proximal joints in the 
fifth stage bear two bristles each. The peduncular joint of the 
appendage becomes divided into two joints with the third stage, and 
into three with the fifth stage. The antennae have a narrow oval 
exopod, whose inner border bears 10, 12, 15, 13 ( circa ), 23 to 25 
feathered bristles respectively in the successive stages. The endo- 
pod is cylindric; at first feather-tipped, then naked. The protopod 
is two-jointed from the third stage and its apical border always 
bears two unequal spines. The maxillae (pi. 3, fig. 34) and ante¬ 
rior maxillipeds call for no especial mention. The latter have a 
two-jointed protopod, a four-jointed endopod, and a flattened exopod 
tipped with six feathered bristles. 
The third maxillipeds and the appendages lying posterior to them 
undergo more metamorphosis than the anterior appendages. These 
maxillipeds are uniramous and rudimentary in the first stage. The 
endopod appears near the base of the distal protopodal joint (pi. 2, 
fig. 24) with the second stage and remains rudimentary throughout 
the larval lile. The exopod in the second and later stages resem¬ 
bles that of the anterior maxillipeds but is smaller. The chelici- 
peds (&) are uniramous in the first and biramous in the second 
stage, but no trace of the chela can be found even in the fifth stage. 
1 he exopod is first functional in the third stage. The second (/), 
third (m ), and fourth (*n) pairs of limbs are uniramous in the first 
