OPHRYOTROCHA PUERILIS. 365 



region, whilst the other leads to the ventral lobe (cirrus) nearer the body. Dorsally are 

 three translucent bristles with slightly flattened tips, which end in a hook. Below the 

 spine are about six compound bristles, the ends of the curved shafts dilated and bevelled 

 for the terminal piece with a simple (?) tip. 



Synonyms. 

 1869. Ophryotrocha puerilis, Claparede and Mecznikow. Zeitschr. f. wiss. Zool., Bel. xix, p. 184, 



Taf. xiii, f. 2. 

 1878. „ Glaparedii, Studer. Arch. £. Naturges., xliv, p. 119, pi. v, f. 11. 



1884. „ minimus, Langerhans. Zeitschr. f. wiss. Zool., Bd. xl, p. 257, Taf. xv, f. 16. 



1885. Staurocephalus Siberti, Mcintosh. Ann. Nat. Hist., ser. 5, vol. xvi, p. 482, pi. xiii, f. 5—8. 

 „ Ophryotrocha pueri lis, Carus. Fauna Medit., p. 217. 



1886. „ ., Yiguier. Arch. Zool. exper., 2 e ser., t. iv, p. 417, pi. xxv, f. 11—17. 



„ Paractius littoralis, Marenzeller. Die Osterr. polarstat. Jan Meyen, III, Zool. Wiirmer, p. 21. 



1888. Ophryotrocha puerilis, De St. Joseph. Ann. Sc. nat., 7 ser., T. v, p. 239, pi. x, f. 96—98. 



„ Paractius mutabilis, idem. Ibid., p. 240, pi. x, f. 103 — 112. 



1890. „ „ Malacuiin. Rev. Biol, du Nord. (Annel. Boulon), T. hi, p. 381. 



„ Ophryotrocha puerilis, Griard. Bullet. Sc. Fr. et Belg., T. xxii, p. 77. 



„ „ „ idem. Ibid., T. xxii, p. 77. 



1892. „ „ Monticelli. Monit. Zool. Italiano, III, p. 250 (fide aut.). 



1893. „ „ Bonnier. Bullet. Sc. Fr. et Belg., T. xxv, p. 198, pis. 1—4. 

 }} „ „ idem. Oompt. Rend. Acad. Sc, T. cxvi, p. 524. 



1895. „ „ (development), Korschelt. Zeitschr. f. wiss. Zool., Bd. lx, p. 543, pis. 



27—34. 

 idem. Ibid., Bd. lx, pp. 543, 689. 

 1902. „ „ Mcintosh. Ann. Nat. Hist., ser. 7, vol. x, p. 257. 



1904. „ „ Allen. Journ. M. B. A., n.s., vol. vii, p. 226. 



1905. „ „ Graeffe. Arbeit. Zool. Stat. Triest., xv, p. 322. 



Habitat.— When at Whitstable in June, 1884, a small Ennicid was noticed in an 

 aquarium belonging to Mr. Sibert Saunders, who kindly forwarded examples to the St. 

 Andrews Marine Laboratory. The specimens had been procured from the oyster- 

 beds at Whitstable, so that in all probability the species haunts the Algaa and other 

 growths attached to the shells of the oysters. Plymouth (Grarstang and Allen). 



Shores of France (Griard and Bonnier) amongst Bryozoa and Ascidians, as well as on 

 the tubes of Sabellaria. Body-cavity of Oucuma/rla plauci at Naples (Monticelli). 



Studer 1 found a very similar species in Kerguelen. 



Head (Plate LXI, fig. 10, and Plate LV, fig. 9) horse-shoe shaped, with a series of 

 rather long palpocils on the whole of the anterior edge. These organs have broad bases, 

 taper to a fine point, and apparently are of great tactile sensibility. Their motions on the 

 edge of the snout are so lively that it seems to be ciliated. The number of eyes is variable, 

 two being situated externally in a dimple behind the dorsal tentacle. They are simple 

 pigment-spots, blackish by reflected and pale brownish by transmitted light. The snout 

 often shows a slight furrow nearly opposite each eye, apparently the second ciliated crown 

 of Bonnier. On the summit of the head just in front of the nuchal fold is a small pair 

 of eyes placed near each other, and occasionally a pigment-spot or two in front of these. 



1 ' Archiv f. Naturges.,' 1878, p. 119, Taf. v, fig. 11. 



