72 ARENICOLA EOAUDATA. 



number of which is thirteen pairs, viz. from the fifth to the seventeeth) bearing somewhat 

 cylindrical, digitiform, often branched, ciliated vascular processes ; ventral lip deeply 

 notched in middle of semi-circular halves. Ova oval with a thick zona. The reproductive 

 organs larger than in other species of Arenicola. 



1. Akenicola ecaudata, Johnston, 1835. Plate LXXXVIII, fig. 8; Plate X.CV, figs. 10 

 and 10 a — ventrolateral view and anterior end; Plate CIII, figs. 13 — 13 b — bristles 

 and hook. 



Specific Characters. — Prostomium conical ; otocysts closed, with a number of spherical 

 refringent otoliths. Proboscis with soft, rounded papillae. Nineteen to forty pairs of 

 gills, the first on setigerous segment 16; 3 — 9 terminal segments devoid of branchiae. 

 Thirteen pairs of segmental organs opening on segments 5 — 17. Twelve pairs of large 

 gonads. Testis in male produced into one or more large, thin reniform lobes ; ovary in 

 female with as many as thirty digitiform vascular processes bearing ova. 130 — 180 mm. 

 long. Anterior diaphragm with two elongated sacs ; abdominal diaphragms from the 

 eighteenth bristled segment. Dorsal bristles alternate, with a very narrow wing; hooks 

 with a longer or more acute rostrum than in A. marina, and the two spines on the crown 

 are larger and longer. Yellowish-red or dark red, and some are dark green with 

 metallic lustre. The post-larval form is distinguished by the extension of the bristles and 

 hooks almost to the hinder extremity and the closed statocsyts. Thirteen pairs of 

 segmental organs. A hook temporarily occurs in the dorsal division of the foot in the 

 last six segments. 



Synonyms. 

 1835. Arenicola ecaudata, Johnston. Loudon's Mag. Nat. Hist., viii, p. 566, f. 54. 

 1840. „ ,, sp., Grube. Anat. Kiemen., p. 3. 



1842. „ „ Chenu. Illust. Conch., i, pp. 1, 12, pi. i, fig. 5. 



1843. „ BoecM, Rathke. Nova Acta Acad. Leop.-Car., xx, p. 181, tab. 8, f. 19 — 22. 

 1851. ,, branchialis, Grube. Fam. Annel., pp. 76 and 136. 



1853. Lumbricus marinus (another species), Dalyell. Pow. Creat., ii, p. 137, pi. xix, figs. 4 — 7. 



„ Arenicola BoecM, Sars. Nyt Mag. f. Naturvid., vii, p. 381. 



1865. „ ecaudata, Johnston. Cat. Worms Brit. Mus., pp. 231, 345, fig. 42. 

 „ „ branchialis (partim), idem. Ibid., p. 231. 



„ „ ecaudata and BoecM, De Quatrefages. Annel., ii, pp. 265 and 266. 



1866. „ „ Lankester. Ann. Nat. Hist , ser. 3, xvii, p. 390. 



1867. ,, „ Malmgren. Annul. Polych., p, 79. 



1870. „ „ Mcintosh. Rep. 39th Meet. Brit. Assoc, p. 90. 



1873. „ „ Lapont. Act. Soc. Linn. Bordeaux, xxviii, p. 264. 



1874. „ „ Malm. K. Vet, Handl. Goteborg, xiv, pp. 88 and 189. 



1879. „ „ Tauber. Annul. Danica., p. 110. 



1880. „ „ Storm. Kgl. Norske Vidensk Selsk. Skr., p. 95. 

 1883. „ „ Levinsen. Aftr. Yid. Meddel. Foren. Kjobenh., p. 92. 

 1885. „ „ Koehler. Ann. Sc. nat., ser. 6, t. xx, art. 4. 



1S8Q - v » Harvey Gibson. First Rep. Fauna Liverp. Bay, p. 156. 



