154 Part I11.— Twenty-first Annual Report 
sort is poured out on the blades. The other hairs on the hand midway 
between the blade and the edge resemble those close to the latter in 
being stouter and less tapering than the hairs on the margins of the 
hand, dactyl, and other joints. When the jaws are closed their hook 
terminations cross over one another and interlock. 
2-5 PrerEtopops. In general appearance the remaining four pereiopods 
resemble one another much, but they ure at once separated into two 
groups. The fifth pereiopod is easily distinguished from the others by 
the presence of the long bristles on the dactylopodite. It is moreover 
considerably smaller than the other three. The second, third, and 
fourth limbs on careful examination show distinctive characters by 
which each may be recognised apart from the others. 
The number and arrangements of the hairs which were found on each 
limb are shown in the drawings: it is only necessary to draw attention 
to the distinguishing marks. They are found on the dactylopodite and 
propodite. In the second (Fig. 95) and third (Fig. 93) pereiopods there 
are on the under surface of the dactylopodite three toothed spines. The 
integument where these are attached is thickened and strengthened 
(Figs. 94 and 92). On the distal lower corner of the propodite there 
is another of these toothed spines (Figs. 91, 93, and 95). In the fourth 
pereiopod the last-mentioned toothed spine is absent (Figs. 89, 99). The 
latter appendage is by this fact separated from the second and third 
pereiopods. The second pereiopod may be readily distinguished froin 
the third by its possessing a long spine (sp) on the dorsal surface of the 
dactylopodite (Fig. 95). 
The hairs found on the fifth pereiopod are shown in Fig. 105. A 
little way short of the tip of the dactylopedite three long curved bristles 
are attached to the lower edge of joint (Fig. 102). The stoutest bristle 
is, on its last third, furnished on the inner side of its curve with a 
double row of teeth (Fig. 96); in one row the teeth are very large, in 
the other much smaller. The longest bristle is more slender than the 
preceding, and is minutely serrated at its tip. The short bristle is 
smooth. 
1. (Figs, 100, 113, 111, 116, 108, and 110.) The pereiopods have 
changed considerably. The large hook is absent from the chela, and 
the propodite and dactylopodite have no toothed thorns. The fifth 
pereiopod resembles the second, third, and fourth. They are still, 
however, very different from those of the adult stage. 
All are profusely supplied with hairs, plain and ciliated ; they are 
also covered with the minute “‘needle-point” cilia. ‘The anterior surface 
of the chela has comparatively few of these little teeth. On the 
coxopodite, basi-ischiopodite, meropodite, carpopodite, the ‘‘ needle- 
point” cilia are restricted to the borders of the joints. There are few 
near the jaws; some are found on the hand. The posterior surface is 
thickly covered, with the exception of the greater part of the dactylo- 
podite. On the other pereiopods the “ needle-point ” cilia are present 
on both sides. 
The sparsely plumose (or ciliated) hairs on the limbs (Fig. 107) have 
the cilia arranged all round the stem of the hair. 
The chela (Figs. 100 and 113) is very thickly provided with ciliated 
hairs. The posterior surface is shown in Fig. 100 and the posterior in 
Fig. 113. The knife-blades are not exactly on the same level, so that 
they pass on to one another when the jaws are closed. The hinge of 
the dactylopodite is seen in Fig. 115. On the carpopodite there is a 
hooked tooth (Fig. 133). 
There are in this stage no marks such as served to distinguish the 
limbs from one another in the Megalops; minute differences which have 
