POTTS—POLYCH ATA: AMPHINOMID#, 363 
Genus AMPHINOME, Bruguiére. 
8. Amphinome rostrata (Pallas). 
Aphrodita rostrata, Pallas, Misc. Zool. p. 106, tab. viii. figs. 14-18 (1766). 
Amphinome rostrata, McIntosh, Polychieta, ‘ Challenger’ Reports, p. 21. 
The examples of this species show some discrepancy with the most recent account, that 
of McIntosh, so that some discussion of the points at issue is here given. 
The characteristic slate-blue of the body and ferruginous hue of the tentacles and 
branchiz are well shown. So far as can be seen in the rather bad state of preservation, 
the structure of the head is typical. The gills appear to be even more densely 
branching than the ‘ Challenger’ specimens from the Bermudas. From a common base 
spring two main divisions, one inner, the other outer, which both give off five or six 
stout branches, dividing again into numerous terminal twigs. 
Both dorsal and ventral setze appear to be quite free from serration, while both kinds 
of dorsal bristles in McIntosh’s specimens have this character. It is not possible to 
recognise the first stout type of dorsal seta described in the ‘Challenger’ Report, all 
appearing to end in long tapering tips. While an authoritative description of the 
setze in these specimens can hardly be given, it must be pointed out that e.g. in 
Quatrefages’s description of A. rostrata he refers to the dorsal sete as tapering and 
smooth, and describes only a single type amongst them. It is noticeable that his 
material came from the Gulf of Bengal, Amboina, and the China Sea, and the suggestion 
may be made that the Atlantic form as described by McIntosh differs from the eastern 
form. 
On the ventral surface segmental apertures appear, which are probably the external 
openings of the nephridia. A pair is found on each segment between the eighth and the 
end, and each one occurs inwards from the ventral bundle of setze upon a rather 
broad papilla. 
Locality. Goidu, Horsburgh Atoll, Maldives. ‘From a backwater full of weed and 
decaying vegetable matter.” 
9. Amphinome maldivensis, sp.n. (Plate 45. figs. 14,15; Plate 46. figs. 12-17.) 
Measurements. 68 mm. in length, 11 mm. in width; no. of segments 55. 
This amphinomid is remarkable for its grub-like form, a consequence of the 
insignificant development of the setigerous lobes of the parapodia. It has a tetragonal 
cross-section and tapers only slightly towards the head and tail, both being rounded, and 
the former only a little more pointed than the latter. The worm possesses a uniform 
flesh-colour in spirit, and while the ventral surface is smooth, the dorsum is wrinkled 
and covered with slight elevations. The prostomium is invisible from the dorsal 
surface, as in the contracted state of the worm it is tucked under the ventral surface 
and surrounded by the lateral parts of the first segment. It was necessary to make an 
incision from the ventral side to examine its structure. 
The head (Pl. 45. figs. 14, 15) is very similar to that of A. djiboulensis, of which a 
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