102 
they were in the early form of larva, altho 
they are only a further elaboration of the 
The support e (fig. 2) has 
become so reduced that the dorsal supports 
appear simply to cross one another (fig. 4, 
e). The supports which pass anteriorly 
from e have united at their ends to form a 
clypeus (not shown in the figure). The sup- 
port f (fig. 2), which was slender in the 
early form, has entirely disappeared. The 
supports @ and m remain essentially the 
same as they were in the early form, but d, 
which at first united almost directly with d, 
has become separated from it, to allow of 
the interposition of a support c, which 
passes forward and unites, at /, with a 
branch (k) from 6, the whole portion at / 
serving as attachment for a muscle to 
extend the labium and maxillae. The 
chitinous supports of the labium and 
maxillae have changed, as will be seen 
later. 
The labrum (fig. 4, 0; fig. 3, 0’) has 
nearly the same outline as in the early form. 
The anterior portion, especially in the very 
last larval stage, is beset with hairs. It 
has two oblique thickenings in each lobe, 
and a Y-shaped thickening through the mid- 
dle. The labrum is protrusile, retractile, 
and slightly movable laterally, as in the 
early form. 
The mandibles (fig. 4, n; fig. 3, n’) 
have characters similar to those which 
they had in the early form. The small 
teeth are, however, absent, and, in their 
place, a ridge extends along the under side 
of the mandible from the large apical teeth 
to the base. The origin and insertion of 
the extensor and flexor muscles are on 
places corresponding to their origin and 
insertion in the early form. 
same plan. 
PSYCHE. 
The maxillae in the later form (fig. 4, 
r; fig. 3, 7”) have undergone considerable 
change in their appearance from that in the 
early form. They are now of the form 
common to lepidopterous larvae —an out- 
ward jointed portion, the maxillary palpus, 
and a double inner jointed portion, the 
maxilla proper. 
The labium (fig. 3, v’) has, in the later 
form, developed a pair of jointed labial 
palpi and a tubular spinneret. The proxi- 
mal portion is hairy. Not only the spin- 
neret, but also the labium itself, can be 
Fie. 4. — Ventral view of the head of Gracila- 
ria syringella in its later larval stages: s, spin- 
neret; other letters as in fig. 2, or explained in 
text. 
turned under, so that the labial palpi are 
directed posteriorly. The position shown 
in fig. 8 is with extended labium; in fig. 
4, with labium folded back. 
The supports which bore the labium and 
maxillae in the early stages (fig. 2, 7) are 
greatly modified in the later stages. The 
support 7 (fig. 4) divides posteriorly into 
two parts, between the ends of which ex- 
tends a support, A (fig. 4). The slightly 
developed line of demarcation between the 
