POLYCELETA—BENHAM. 
123 
Fig. 118. A dorsal chseta viewed in the plane with two flanges (x 45). 
119. A dorsal chseta viewed in the plane at right angles to the above ; it is now 
curved, and has one broader flange ( X 45). 
120. A portion of a dorsal chseta lying on its two-flanged side, with the third flange 
projecting upwards ( X 720). 
121. The tenth abdominal neuropod (X 20 ),—d., distal process ; p., proximal 
papilla. 
122. Neuropodial uncinus ( X 360). 
123. The same viewed from above. 
Amythas membranifera (figs. 124-132). 
Fig. 124. Anterior end dorsal view (natural size). The missing gills are indicated by 
the dotted lines. 
125. Anterior end (enlarged)— fj., the anterior gill of right side; g. 2, y. 3, the 
gills, or their bases, of the second and third pairs ; hr ., branchiferous segment; 
pr., prostomium. 
126. Side view of anterior region ( X 2)— pe., peristomium ; other letters as above. 
127. Anterior end, seen from in front (X 3), with the tentacular membrane ( t.m .) 
pressed downwards— l., lateral region of the lower lip (peristomium) ; pr., 
prostomium ; s.o., supra-oral arch. 
128. View from below of the anterior end, dissected from the left side, and the floor 
pressed down— gL, ventral gland shields ; l.a., lateral region of the supraoral 
arch ; i.l., inner lower lip or sphincter ; nrp., neuropods ; pe., peristomium ; 
t.m., tentacular membrane. 
129. Side view of the abdominal segments. 
130. Thoracic uncinus ( X 360). 
131. Abdominal uncinus ( X 360). 
132. Abdominal uncinus, viewed from above ( X 360). 
