. Discovery reports. Discovery (Ship); Scientific expeditions; Ocean; Antarctica; Falkland Islands. 132 DISCOVERY REPORTS of eyes. There is a characteristic pair of divergent nuchal epaulettes reaching back to the 3rd chaetiger. The tentacles and tentacular cirri are long and unconstricted. The normal dorsal cirri are about half as long as the body is broad. According to Benham the pharynx extends back to the 7th chaetiger, where it bends forward on itself, and turns back to enter the proventriculus, which occupies segments 10-14. The pedal lobes form large, rounded prominences above the brist
. Discovery reports. Discovery (Ship); Scientific expeditions; Ocean; Antarctica; Falkland Islands. 132 DISCOVERY REPORTS of eyes. There is a characteristic pair of divergent nuchal epaulettes reaching back to the 3rd chaetiger. The tentacles and tentacular cirri are long and unconstricted. The normal dorsal cirri are about half as long as the body is broad. According to Benham the pharynx extends back to the 7th chaetiger, where it bends forward on itself, and turns back to enter the proventriculus, which occupies segments 10-14. The pedal lobes form large, rounded prominences above the bristles, and glandular pads are present on the ventral surface. The bristles are bidentate and have the head of the shaft denticulated. Gravier states that there is also in each foot a single, simple capillary bristle. These I have not seen. Sacconereis The specimen from St. WS 228 is a ripe female measuring 18 mm. by i mm. for about 70 chaetigers. There are swimming bristles from the 15th to the 35th chaetigers, and the anterior pair of eyes is greatly enlarged, so as to extend down the sides of the head to the ventral surface. Otherwise it is not modified. Polybostrichus The specimen from St. 42 is a ripe male beginning to turn into a Polybostrichus. Only the head shows signs of modification. The normal eyes have disappeared and their place is taken by a single pair of dark eyes rather deeply embedded in the sides of the head. The anterior pair of appendages shows signs of forking towards its base, or to be more exact, a pair of stout conical lobes appear to have grown out from the head at the point of insertion of the lateral tentacles and to have carried the latter with them attached to the bottom of their outer faces (Fig. 22). In the light of the controversy as to the homology of the anterior bifid appendages in Polybostrichus it may be F'S- ^2- Autolytus charcoti {Poly- , ,-11 11 t bostrichus). Ventral view of head worth remarkmg that the true palps do not seem to be ^^.^^ ^
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