OPISTHOPORUS. 41 
Vlll, Opisthoporus Benson. 
Ep Mon. Pneum: TIE. | p. (25 ;- LIT. p. 96. Dlanford in 
Ann. and Mag. nat, hist. 3d. ser. XIII. 1864. p. 451. — 
Martens Ostas. Zool. II. 1867. p. 110. —- Stoliezka 1n Journ. 
As. Soc. Beng. XLI. 1872. Pt. 2. p. 265. —  Pütel Catal. 
Jo Toxp. po. «919; 
Species : 
l. biciliatus (Pterocyclos) Mouss. (Coll. 1.) I. 40 ( Cyclotus Tay- 
lorianus ). 50 (Pterocyclos). II. 26. III. 36. — Martens Ostas. Zool. 
II. p. 110 *). — Patel Cat. p. 119. —  lssel Moll. Born. p. 73 
(injuneto sequente). —  Cyclostoma 'aylorianum .Pfr.,  Charbonnieri 
FHecl. — Borneo. 
2. ? Q. spiniferus (Cyclostoma) Morelet. 7 
.T. latissime umbilicata, depressa, striatula, albido-fulva, 
flammulis eastaneis, zigzagformibus, subtus pallidioribus, varie- 
gata, spira planulata, medio prominula; anfr. 4!/, sutura pro- 
funda discreti, priores fusco-violacei, convexiuscuh, ultmus 
supra peripheriam angulatus, obsolete plicato-striatus, antice 
vix descendens, spina tubulari albida, recurvata, juxta suturam, 
9 mill. pone aperturam munitus; apertura obliqua, circularis, 
intus variegata; peristoma duplex: internum rectum, continuum, 
prominens; externum albidum, expansum, margine dextro di- 
latato, superne angulatim patente. — Opereulum subeartilagi- 
neum, pallidum, multispirum, oblique lamelloso-striatum, extus 
concaviusculum; nucleo centrah, nitide corneo. — Diam. 17, 
altit. 51/, mill. (M.) 
Cyclostoma. spiniferum .Morelet in Journ. Conch. IX. 1861. p. 177. 
Opisthoporus spiniferus Mart. Ostas. Zool. Il. p. 113. 
*) ,'Testa depressa, late umbilicata, perpendiculariter confertim rugosa, 
seriebus 2 spiralibus ciliorum sat longorum, mollium ornata, virenti-brunnea, 
maculis fuscis latis plus minusve fulgurantibus picta; vertex castaneus pau- 
lum prominulus; anfr. 41/,, convexi, sutura sat profunda, ultimus ad apertu- 
ram descendens, paulo antea tubulo suturali recurvo aperto munitus; apertura 
sat obliqua, circularis; peristoma reflexum, dilatatum, callo junctum, pallide 
flavum, subduplicatum, externum ad suturam sinuatum et effusum. — Oper- 
eulum ealcareum, multispirum, extus planiuseulum, albidum, nucleo nigri- 
eante. — Diam. maj..14— 19, min. 10—14, alt. 61/,; apert. long. — lat, 
61/,— 81/, mill.* 
