AMMOTRYPANE AULOGASTER. 15 



Genus LXXXI. Ammotrypane, 1 H. Rathlce, 1843. 



Head terminating in an acute cone anteriorly, devoid of tentacles and eyes, but it may 

 have nuchal organs. Body elongate, more or less fusiform, muscular, elastic, iridescent 

 and ringed, terminating posteriorly in a scoop or in cirriform processes ; forty-eight or 

 more segments. Mouth on the ventral surface as a transverse slit, from which the 

 proboscis is extruded. Ventral longitudinal muscles prominent. Ventral cirrus present 

 or absent. Terminal pair of cirri enlarged and rather short. Feet slightly developed, 

 simple or biramous, the dorsal cirrus being enlarged into a branchia, the setigerous 

 region being sessile, the bristles simple, long, pale golden, tapering and curved, with fine 

 longitudinal lines. 



A notable contribution was made to this group by H. Rathke, 2 who instituted the 

 genus Ammotrypane, with the species A. aulogaster, A. limacina, and A. cestoides. He 

 gave a good description of their external appearance and of their internal structure, 

 with original figures. 



1. Ammotrypane aulogaster, E. Rathlce, 1843. Plate XOV, figs. 3-3d — head, body, tail 



and foot; Plate CIII, figs. 3 and 3 a — bristles. 



Specific characters. — Head acutely pointed, with a stalked mucro in front, and 

 posterior nuchal organs. Body 2^ ins. long, much elongated, fusiform, rounded dorsally, 

 deeply grooved from end to end ventrally ; feet simple, a single tuft of simple bristles, 

 a large ligulate dorsal cirrus (branchia), and a small ventral cirrus. Segments 55—60. 

 Anus terminating in a scoop-shaped hood opening ventrally, and with four cirri along 

 each border posteriorly, a pair of larger and rather thick cirri being at its base with a 

 more slender median cirrus between them. 



Synonyms. 



1843. Ammotrypane* aulogaster, H. Rathke. Beitr. Fauna Norw., Nova Acta Leop.-Car., t. xx, p. 188, 



Tab. x, f. 1—3, Tab. xi, f. 15. 



1843. Ophelina acuminata, CErsted. Annul. Dan. Consp., p. 45. 



1844. „ „ idem. Arch. f. Naturges., Ed. x, p. Ill, Tab. iii, figs. 24—26. 

 „ ,, „ idem. Region. Mar., p. 78. 



1845. Ophelina aulogaster, Kroyer. Nat. Tidsskr., 2 ser, i, p. 414. 

 1851. Ophelia acuminata, Grube. Fam. Annel., p. 70. 



fi ,, aulogaster, idem. Ibid., pp. 70 and 135. 



1853. Ammotrypane aulogaster, Sars. Nyt Mag. f. Naturvid., vii, p. 391. 

 1857. Ophelia aulogaster, Koren. Ibid., ix, p. 94. 



1859. „ „ Danielssen. Reise, 1858, Norske Yidensk. Skrift., iv, p. 119. 



1861. „ „ idem. Reise, 1857, Nyt Mag. f. Naturvid., xi, p. 53. 



1 Aji/uog and rpviravti, sand-borer. 



2 ( Fauna Norvvegens/ pp. 186-208, Tab. x. 



