Japanese palolo, ceratocephale osawai, n. sp. 11 



and the outer end of the ramus in question. The bristles are 

 exclusively of the setose kind (PL IL, fig. 12) with the blade 

 finely serrated on one edge. They are placed in a bunch, dorsal 

 to both the ligula and the acicula mentioned above. 



The ventral ramus of the parapodium has no ligula, but is 

 supplied with two small and rounded terminal lobes, the upper 

 and the lower. Both are directed outwards and downwards, 

 Further there is present ou the ramus the ventral cirrus (v.o.). 

 This compares well both in size and shape with the distal section 

 of the dorsal cirrus ; but the basal section, clearly distinguishable 

 in the latter, is here only indistinctly indicated in that it shows 

 no bounding constriction against the body proper of the ramus. 

 The acicula (v. a.) is quite similar to that of the dorsal ramus, 

 while the bristles are here of two kinds, the falcate and the 

 setose, and are grouped in four bunches. Of these the lower - 

 anterior bunch consists only of the falcate bristles (PL IL, fig. 

 14). The upper-anterior bunch consists of setose bristles, whose 

 blades are short and finely serrated on one edge (PL IL, fig. 17). 

 The lower-posterior bunch consists of setose bristles whose blades 

 are long and rather coarsely serrated on the convex edge (PL IL, 

 fig. 15). This form of bristles closely resembles that from the 

 ventral ramus of Ceratocephale loveni. The upper-posterior bunch 

 is composed of setose bristles, the longest and most slender of 

 the kind in the entire parapodium (PL II., fig. 16). The blade 

 is slightly curved, with very line serration. 



Variation of the Parapodia. — The parapodia in différent 

 regions of the body are subject to certain variations as regards 

 their size and the relative development of their parts. From the 

 first parapodium (belonging to the second segment) backwards to 



