POLYCH.ETA. 293 



9 or 10 occur they are distinct, when 11 are present the apical tooth is very small. 

 The abdominal notopodia carry a bundle of four spatulate setae. The abdominal 

 uncini show 10 or 11, perhaps sometimes 12 denticulations. All the uncini 

 show the peculiar ribbed structure noted by previous authors in other species 

 (Plate V., fig. 132). 



This species is closely related to PhyllochcBtopterus acicidigerus, described by 

 Crossland from the Maldive Group (' P. Zool. Soc. Lond.,' 1904, p. 278). The 

 aspect of the anterior region varies greatly according to the state of the preserved 

 material ; when well protracted and hardened, it resembles the condition figured by 

 Crossland for P. elioti from Zanzibar (cf. Plate V., fig. 127), except for the absence 

 of eyes in P. herdmani. 



In nine specimens there are ten pairs of thoracic parapodia, in one specimen nine 

 pairs, the latter being the number given for P. aciculigerus. The principal 

 substantial difference appears to be due to the presence in the last-named species 

 of a glandular cirrus of uncertain homologies arising from the centre of the neuro- 

 podial tori of tbe first branchial segment. 



Phyllochaetopterus ramosus, n. sp. Plate V., figs. 133 to 136. 



Locality : A thick cluster of slender brown translucent ramifying tubes (Plate V., 

 fig. 133), overgrown and welded together by foreign incrustations of other tubicolous 

 and colonial organisms and vegetable growths, trawled off Galle, at Station XXXVIII. 



A fairly complete worm measures 25 millims. in length, its tube twice this length, 

 and l - 5 millims. in diameter. The first region of the body consists of 15 segments; 

 the fourth parapodium contains one, sometimes two broad flattened modified setae 

 (Plate V., figs. 134 and 135). The second or branchial region comprises about 

 16 segments. As the worms were all preserved inside their closely investing tubes, 

 the branchial region is not preserved sufficiently well to show details clearly. 

 Practically it may be distinguished from the third or abdominal region by its long 

 styliform notopodia, each supported by not more than four internal slender setae. 

 The abdominal notopodia are clavate papillae, each supported by a single seta. The 

 long tentacles are coloured with brown patches which give them a banded 

 appearance ; they are followed by the small second pair of tentacles. The pro- 

 stomium carries a pair of elongated eye-spots. 



This species represents P. pictus, Crossland (' P. Zool. Soc, London,' 1903, p. 174), 

 from which it differs in the character of the modified setae of the fourth parapodia, 

 the number of branchial segments and the character of the tubes. In the anterior 

 branchial region the uncinigerous tori encircle the sides of the body, appearing like 

 silver bands by reflected light. The uncini are excessively numerous in these bands, 

 and are disposed in a polystichous manner, nine or ten closely packed rows. Each 

 unoinus shows about twenty minute teeth, the lower end terminating in a blunt, 

 curved process (Plate V., fig. 136). 



