1904.] POLYCn.ETA OF THE MALDIVE ARCHIPELAGO. 285 



indicated (brownish with pale dots) stretches to the 20th or 25th 

 segment and fades into the general brownish iridescence of the 

 body." 



The prostomiuni is of chai-acteristic shape and size in both, but 

 a constant difference is found in the median notch of its anterioi- 

 border, which is much less deep in L. ninetta. In that species 

 the short cone-shaped tentacles do not reach its anterior border, 

 while those of L. collaris which are more gently tapered extend 

 a little beyond it, and the characteristic crescentic or kidney- 

 shaped eyes of the Indian Ocean form are replaced by round or 

 oval ones in that of the Mediterranean and Channel. 



The dental apparatus and especially the very characteristic 

 plates of the lower jaw form a striking feature common to both 

 species. The feet and setae also afford no distinction, as though 

 the articulated pieces of the compound setae appear a little longer 

 in the European form, this feature vaiies widely in specimens 

 from the Indian Ocean. 



List op Literature. 



Genus Chcetopterus. 



(1) ScHMARDA. — ' Neue wirbellose Thiere.' 1861. 



(2) JoURDAiN. — Mem. de la Soc. nat. des Sci. nat. de Cherbovirg, 



xi. pp. 76-80 (1865). 



(3) Lespes. — "Etude anatomique sur un Chetoptere " {C. hrevis). 



Ann. Sci. Nat. (5) xv. 1874, Art. 14. 



(4) Grube.— Proc. Roy. Soc. 1874, p. 325. 



Grube. — " Annulata Semperiana." Mem. de I'Acad. Imp. 

 de St. Petersbourg, vii*^ serie, t. xxv. no. 8. 



(5) Marenzeller. — " Siidjapanische Anneliden." Denkschr. d. 



k. Akad. der Wissenschaften, Mathem. - naturwiss. 

 Classe, Bd. xli. (1879). 



(6) Joyeux-Laffuie. — " Monographic du Chetoptere." Arch. 



Zool. exp. et gen. 1890. 



(7) Ehlers. — ' Hamburger Magalhaensischen Sammelreise.' 



(8) De St. Joseph. — " Annelides Polychetes des Cotes de Dinard." 



Ann. Sci. Nat. 8^ ser. t. xvii. (1894). 



Genus Phyllochcetopterus. 



(1) Claparede. — ' Annelides du Golfe de Naples.' 1868. 



(2) Langerhans. — " TJeber einige Oanarischen Anneliden." Nov. 



Act. der Leop.-Carol. Deutsche Akad., Bd. xliii. (1881). 



(3) McIntosh.— ' Challenger' Reports, vol. xii. 1885, p. 374. 



(4) RoULE. — " Campagne du 'Caudan'." Ann. de I'Univ. de 



Lyon, 1896. 



(5) Lo Bianco.— Ann. Pub. nel Golfo di Napoli. 1892. 



