126 
THE VOYAGE OF H.M.S. CHALLENGEE. 
Habitat . — Fiji Islands (Semper, Ludwig), Mauritius (Haacke, Ludwig), Ceram 
(Ludwig). 
(Mus. Holm.) Eleven specimens of this very characteristic and easily recognised 
form; two dredged at Fiji Islands and nine at Tonga. 
Genus 7. Amphieyelus, Bell, .1884. 
Tentacles twenty-four, in two circles, those in the inner circle smaller, arranged in 
pairs, ten in number and radial in position ; those of the outer fourteen, subequal. 
Calcareous ring and other deposits, excepting terminal plates in the pedicels and 
rods in the tentacles, absent. Ambulacral appendages in the shape of pedicels 
confined to the ambulacra and arranged in regular rows ; in the dorsal ambulacra 
they are set in pairs, but are a little more irregular and crowded in the ventral. 
Interambulacra naked. 
Amphieyelus jajponicus, Bell, 1884. 
Habitat. — Lat. 41° 12' H., long. 140° 45' E.; 43 fathoms; sand and mud (Bell). 
A further examination will possibly shew such a close relation between this species 
and Pseudocucumis acicula, that they may be referred to the same genus. 
Subfamily 2. Gasteopoda. 
Ambulacral appendages in the shape of pedicels alone, arranged in distinct rows on 
the fiat, discoidal, sole-like, ventral surface. The convex dorsal surface naked, 
mostly covered with large scales. Tentacles ten, exceptionally fifteen, nearly 
equal. Calcareous ring of ten simple pieces, not prolonged posteriorly. 
Genus 8. Psolus, Oken, 1815. 
I. Tentacles ten. 
A. Pedicels in three complete longitudinal series. 
1. Dorsal perisome devoid of large seales, only with minute plates or grains. 
Psolus regalis, Verrill, 1866 ; Bell, 1882. Psolus granulatus, Ayres, 1854. 
Body like that of Psolus phantapus, though longer and narrower, and “ its elongate- 
conical tail is much more nearly the result of a gradual tapering of the body ” 
(according to Bell). The sole quadrangular. The lateral series of pedicels 
composed of about four rows ; the odd series much narrower. Dorsal perisome 
