10 
CyCLOSTOMACEA. | 
CycLOoTUS CONICUS. 
Testa conico-turbinata, late umbilicata, sub epidermide sordide 
brunea aureonitens, spiraliter lirata; apex acuminatus; anfr. 5, 
convexi, sutura profunde discreti, ultimus rotundatus, liris 8-9 
elevatis, mediana nigricante, piligera, basi levi ; apertura cir- 
cularis ; peristoma duplex, internum rectum, album, continuum, 
margini columellari appressum, externum interruptum, breviter 
expansum, nigricans. Operc. typicum. 
Diam. maj. 10, min. 8, alt. 10 mill. 
This species comes next to C. touwrannensis, Souleyet, from Cochin 
China, but is distinguished from it by the sculpture, by the haired 
keel, and by the higher form of the shell. 
Leg. Bowring. 
OPpISTHOPORUS SIAMENSIS, 0. 
Testa discoidea, late umbilicata, striatula, flavida, fusco-fulgu- 
rata, vertice prominulo ; anfr. 44, convewiusculi, sutura pro- 
funda discreti, ultimus rotundatus, antice descendens, non 
solutus, linea mediana pilifera, tubulo recurvo aperto 6 mill. 
pone aperturam munitus ; apertura circularis; peristoma du- 
plex, internum rectum, continuum, externum interruptum, bre- 
viter expansum, superne alatim dilatatum. Operculum calea- 
reum, multispirum, planum, margine incrassato, cavo. 
Diam. maj. 19, min. 14, alt. 7 mill. 
Leg. Bowring. 
Allied to O. diciliatus, Mouss. and O. euryomphalus, Pfr. 
Prerocycios (subg. SprracuLuM) HovsEI, Haines, Ann. of 
Lyc. N. H. of New York, Oct. 1855, vi. p. 157, pl. 5. f. 12-15; 
Pfr. Suppl. p. 29. 
In this species the end of the last whorl is separated from the 
preceding ; the operculum is remarkable from its cylindrical form. 
Leg. House. 
ALyc£us pistortus, Haines, l. c. pl. 5. f. 5-8; Pfr. Suppl. 
p- 33. 
Leg. House. : 
CycLopPHorws SIAMENSIS, Sow.Thes. Suppl?pl. 31 A. f. 292, 293; 
Pfr. Mon. p. 66 ; Gray, Cat. Cycl. p. 37. 
Operculum cartilagineo-corneum, multispirum, crassiusculum, 
extus concavum, albidum, intus aurantium, nucleo centrali, 
mammillato, sanguineo. 
In our specimen the last whorl is rather subangulated. 
Leg. Bowring. 
CycLopHorus FLoRIDUuS, Pfr. Proc. Zool. Soc. 1854, p. 300; 
Mon. Pneumonop. Suppl. p. 43. 
Leg. House. 
