588 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 
ventrally over the posterior ends of the lateral lobes of 
the brain, and the median tentacle slightly in front of 
the lateral ones. 
The thick-walled pouches of the oesophagus coalesce 
to form the muscular pharynx in which the rudiments of 
the jaws may be recognised as chitinous projections 
(Pl. I., fig. 18). The parapodia of the ninth segment 
have now attained the full development of their parts. 
On the peristomial segment one or two slightly curved 
and extremely stout serrate setae project between the 
dorsal and ventral tentacular cirri, whilst the remaining 
segments bear parapodia with both dorsal and ventral tufts 
of longer serrate setae (Pl. I., fig. 20), of which the 
ventral are longer and more slender than the dorsal. 
A short line of 20 cilia often occurs at this stage 
on the proximal part of either the dorsal or ventral surface 
of the ramus of each parapodium, and sometimes on both 
surfaces; similar cilia occur just in front of the bases of 
the peristomial cirri. Hacker (1896: p. 111, foot-note 2) 
notes the presence of intertrochal cilia on the dorsal rami 
of the parapodia of his Naples Polynoé larva. Rudiments ) 
of the tenth segment appear, but its parapodia remain 
very small and bear no setae during this stage, in which 
there is indeed very little development in the body region; © 
and Hacker has already pointed out that it is a period of 
comparative quiescence. A median caudal appendage, 
20% long by 4# broad, is now present. 
Further development.—The nectochaeta 
stage of Polynoé is regarded as terminating soon after the 
disappearance of the ciliated band, when the size of the 
head is still further reduced and the tentacles and palps 
lengthen till their final proportions are reached; the 
body-segments elongate again and additional ones rapidly 
develop, so that, so far as general proportions are con- 
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