246 
membrane. The latter shows a thin area through which 
later the larva forces its way. x 210. 
Fig. 75. Larva three days (72 hours) after fertilisa- 
tion of the egg. Dorsal aspect. Both ciliated bands are 
now present, and there are two eyes on the prostomiun. 
Ten minutes after the drawing was made the larva forced 
its way through the thin area in the upper portion of the 
vitelline membrane. x 210. 
Fig. 76. Larva one day after hatching. Dorsal 
aspect. ‘T'wo short spade-shaped sete are present. The 
anterior and posterior ciliated bands and the eyes are also 
shown. The specimen was slightly compressed by the 
cover-glass and therefore appears a little broader than it 
should be. x 210. 
Fig. 77. Larva twelve days. after hatching. Seen 
from the right side. The prostomium bears two eyes and 
several small groups of sense hairs. Sete are present in 
three segments, in the first two of which both notopodial 
and neuropodial sete may be seen. The notopodial sete 
are of two kinds. The alimentary canal is complete from 
mouth to anus, the middle portion is dilated with yolk. 
The eelom is obvious post-orally. The anterior girdle of 
cilia has entirely, and the posterior one almost, disappeared. 
The anterior portion of the ventral band of cilia still 
remains. x 210. 
Fig. 78. A (notopodial) seta from the larva shown in 
hie. VO |< LOO: 
Fig. 79. Two sete from the larva shown in fig. 77. 
Fig. 794. One of the neuropodial crotchets. The 
dotted line indicates the level of the epidermis. x 1000. 
Fig. 9B, The distal portion of one of the notopodial 
sete. The other seta in the same notopodium is sunilar 
to the one shown in fig. 78. x 1000. 
