Peroderma). P. bellottii, which I have examined myself, has only 
3 pairs of feet developed; but behind the last pair a merely rudi- 
mentary structure is seen, which may perhaps represent a fourth 
pair. The 3 pairs are arranged with large interspaces (efr. text- 
figure 1, pag. 12), in which small symmetrically scattered chitinous 
pårcels åre found, looking like ventral parts of the segments, burst 
from each other by the distension of the body during its growth. 
"The feet, compared with those of Sarcotretes, are smaller and of 
a somewhat different shape, and the same may be said regarding 
the antennæ, first maxillipeds and sipho; further there is a vestigial 
pair of 2nd maxillipeds (like those of Lernæa branchialis) about 
midway between the first maxillipeds and anterior pair of feet; 
the dorsal shield of the cephalothorax has quite another shape, 
being distended and burst into pieces at the margins, probably a 
Consequence of the greater development of the two lateral processes, 
which are here somewhat asymmetrical and clumsily branched at 
their outer ends. Only the first of the abdominal terga seems 
preserved; it is here asymmetrically turned to the left side on a 
slight swelling immediately behind the large processes. These 
differences together with the presence of the branched "frontal" 
aåppendages seem to me to .prevent the inclusion of my Sarco- 
tretes in the same genus. Speaking generally, the latter shows more 
likeness to the genus Lernæenicus, f. ex. L. encrasicholi (Turton) 
which I know from my own examination!); but, as already stated, 
this genus possesses four pairs of feet. 
2. The stages of metamorphosis (Pl. II, Figs. 11-15, 22-26). 
A. The vyoungest stage which I have found agrees in the 
manin features mk the stage of Lernæa branchialis, which Claus 
N This species has a short median outgrowth from the dorsal side of 
the cephalothorax about at the level of the two large lateral processes, 
and furthermore on the ventral side, in front of the needs a 
pair of short, clumsy outgrowths. These structures as well as 
maxillipeds and maxillæ have been overlooked by A. Scott (19 za 
P. 94, Pl. II, Figs. 6—9). 
