128 Cl'CLOPHORIDJE, 



Shell widely uuibilicated, subdiscoid, last v\horl solute, descend- 

 ing laterally ; peristome free, notched above, with a more or less 

 imperfect reiiexed tube at the end of tlie notch. Operciduni 

 shortly cylindrical, multispiral, deeply excavated within, nucleus 

 flat, smooth. 



179. Rhiostoma haughtoni, Benson. 



Rhiostoma hawjhtoni, Benson, A. M. N. H. ser. 3, v, 1860, p. 96 ; 

 Pfeiti'er, Mon. Pueum. Suppl. 2, 1865, p. 39 ; Stoliczka, 

 J.A. S.B. xl, 187J, p. 150; Theobald, Cat. Shells Brit. India, 

 1876, p. 37 : Kobelt & Mollendorff, Nacbr. Ueuts. Malak. Ges. 

 xxix, 1897,' p. 115 ; id., Oat. Pueum. 1899, p. 27 ; Kobelt, Das 

 Tierreich, Lief. 16, 1902, p. 177, tig. 38; id., Conch.-Cab., 

 Cyclophoridae, ii, 1910, p. 759, pi. 110, fig. 14, pi. Ill, figs. 14- 

 16. 



Pterocydos haughtoni, Reeve, Coucb. Icon, xiv, 1863, pi. 5, fig. 30. 



Pterocyclos { Rhiostoma) hanghtoni, Yi&wley & Theobald, Coucb. Ind. 

 1870, pi. '5, tig. 10. 



Pterocyclus [Rhiostoma) haughtoni, Nevill, Hand List, i, 1878, p. 262. 



Original description : — " Testa late umbilicata, convexo-depressa, 

 solidiuscula, oblique scabre striatula, superne castanea, subtus 

 albida, fascia angusta mediana saturatiore, utrinque angulato- 

 marmorata, ornata ; spira depresso-conoidea, apice prominulo 

 obtusiusculo, sutura impressa ; anfractibus 5, convexiusculis, 

 ultimo cylindrico, antice longe soluto, lateraliter descendente, 

 superne carina obtusa a sutura usque ad tubulum marginalem 

 decurrente niunito ; apertura libera, obliqua, diagonali, circuLiri ; 

 peristoraate subduplici, extus incrassato, reflexiusculo, superne 

 ad sinistrani inciso, tubulo imperfecto, antice aperto, sinistrorse 

 erecto, riniam coronante, munito ; umbilico perspectivo, profundo ; 

 operculo testaceo, multispirato, breviter cylindrico, a))ice planato, 

 l^vigato, anfractibus arete convolutis, niarginibus acute carinatis, 

 spatiis intersitis epidermide scabra vestitis ; intus profunde 

 excavato, polito. 



"Diam. major 21, minor 11, axis 8i mill." (Benson.) 

 Hah. Burma : Moulraain {Haughton, Theohald) ; Damotba, N.E. 

 of Moulmain {Stoliczlca). 



Fig. 22. — Rliiosfoma haughtoni. 



" Young specimens have no trace of the upper notch at the 

 outer lip and are generally undistinguishable from the planorboid 

 Cyclopliori, like the Ceylon C. anmdatus, Troscb., or the Nilgherry 



