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Arquivos de Zoologia

Ducts of salivary glands large, run through nerve ring, attached to dorsal wali of anterior esophagus until above cited aperture in buccal mass. Esophagus complex shaped (figs 322, 323), with two longitudinal lateral pouches bearing several transversal, somewhat uniform folds. In anterior esophagus these pouches are ventral, after nerve ring they twist and become dorsal. In opposite side of these pouches two Iow longitudinal folds. No visible glands in inner esophageal surface. Poste-rior esophagus simple, without folds. Stornach (fig. 324) very large and complex (Marcus & Marcus: 504-505, fig. 6; Houbrick, 1974: 44, fig, 15); esophagus opens near intestine-style sac origin; central pad very large, almost touching posterior limit of stornach, somewhat free, only attached in ventral gastric surface by a longitudinal thin lamina; gastric shield and dorsal sorting area well developed; a smali ring-like fold, continuous with anterior region of central pad, separate two gastric chambers, a larger and posterior, which bears most gastric structures, and other smali and anterior, with smooth surface, preceding style sac-intestine apertures; crescentic ridge absent or only visible in left-posterior region of central pad as an annex fold (fig. 324: er), lntestine and style sac united by a longitudinal aperture of almost their entire dorsal region; but this connection is maintained closed. Style sac long, style present. lntestine, after separated from style sac, contours its posterior region, runs newly anteriorly in dorsal region of style sac where presents two loops in M-shape (figs 321, 324), maintained in this position by smali muscle fibers between intestine and style sac. Rectum vcry broad, with successive obliąue folds (fig. 317). Fecal pellets obliąue, compacted. Anus siphoned. Other details of digestive system in Marcus & Marcus (1964: 502-505).

Genital system. Małe organs described by Marcus & Marcus (1964: 505-506, fig. 8). Open pallial spermoduct very long (fig. 317).

Female organs also described by Marcus & Marcus (1964: 506-507, figs 9-11). It is interesting to notę presence of seminal receptacle and a bursa copulatrix; albumen gland introduced in yentral wali of kidney chamber, in some specimens this gland compress greatly kidney tissue. Ovopositor (figs 315,316) in right-dorsal side of foot, bearing two parallel folds; posterior fold narrow and long; anterioT fold shorter and broader in its distal end;

between both folds a deep furrow.

Nervous system. Nerve ring as described j by Marcus & Marcus (1964:501-502, fig.3), situated posteriorly in esophagus, removed from buccal mass (fig. 320).

Measurements (in mm). MZSP 28259:35.3 by 14.7 (figured specimen); 35.8 by 15.3; 38.0 by 15.0.

Distribution. From Florida, USA, to Santa Catarina, Brazil.

Habitat. Intertidal or Iow infratidal, moving on mud or muddy sand bottoms, generally among rocks i

Materiał examined. Brazil; Pemambuco; | Ponta das Pedras, 14 specimens, MZSP 28261 (Montouchet col, 30/viii/l 970). Bahia; Salvador, Ribeira beach, 12 specimens, MZSP 28472 (Simo- j ne col., 27/ii/1997). Sao Paulo; Ubatuba, Enseada j das Palmas, 51 specimens, MZSP 28259 (28/ii/ j 1962); Base Norte IOUSP, 14 km SW downtown, i 23°57’S 45°06’W, 43 specimens, MZSP 28260 \ (Marcus & Marcus col., ii/1964) (lot studied by j Marcus & Marcus, 1964); Sao Sebastiao, Sao Frań- j cisco beach, 1 specimen observed alive, MZSP 28349 (25/x/l 996, Simone col.); Alcatrazes lsland, < Porto dos Faroleiros, 1 specimen observed alive, ‘ MZSP 28324 (01/xii/1996, Simone col., Projeto . Alcatrazes).    ¹

Genus Bittium Leach in Gray, 1847 (Type species: Strombiformis reticulatum

daCosta, 1778)

Bittium varium (Pfeiffer, 1840)

(Figs 27, 28, 48, 64, 78, 102, 103, 329-344)

CerUhium varium Pfeiffer, 1840: 256-257. Cerilhium gibberulum C. B. Adams, 1845: 5;

Reeve, 1865 (pl. 18, fig. 123).

Cerilhium (Bittium) gibberulum: Smith, 1890a: 291; Kobelt, 1898: 245 (pl. 43, fig. 1).

Bittium varium: Dali, 1889a: 258; 1889b: 140; Morretes, 1949:79; Warmke & Abbott, 1961: 73 (pl. 13, fig. h); Marcus & Marcus, 1963: 74-91 (f. 77-95); Rios, 1970: 43; Houbrick, 1977: 104 (f. 4-5); Rios, 1985: 51 (pl. 19, f. 229); Jong& Coomans, 1988:44 (pl. 15, fig. 212); Rios, 1994: 63 (pl. 21, f. 238). Diastoma varium: Abbott, 1974: 107 (fig. 1037);

Rios, 1975: 49 (pl. 13, f. 179).