384 OPISTHOPORUS. MYCHOPOMA. RHIOSTOMA. SPIRACULUM. 
acutiuscula, violaceo-nigricans; anfr. D convexiusculi, juxta 
suturam planulati et striati, ultimus dilatatus, teres, leviter 
descendens, demum breviter et anguste solutus, spiraculo brevi, 
terminal, juxta anfractum penultimum munitus; apertura ob- 
liqua, circularis; peristoma simplex, vix expansiusculum, su- 
perne ad spiraculum breviter emarginatum. —  Operculum 
cylindrieum, arctispirum, supra planulatum, apice leviter im- 
merso, subtus omnino excavatum, latere acute spirahter sul- 
cato. — Diam. maj. 22, min. 17, alüt. 19 mill; diam, apert. 
( mill.* (M.) 
Pterocyclos Cambodjensis Morelet Séries conch. IV. 1875. p. 286. t. 13. f. 1. 
Habitat circa. Battambang Cambodjae. 
Obs. Peraffinis videtur O. Cochinchinensi Pfr. 
IX. Mychopoma. Blanford. 
(p. 45.) 
Genus ex sententia Beddomei Cyathopomatis subgeneri 
Jerdoniae injungendum. 
* 
l. hirsutum Bedd. — Conch. Ind. VII. t. 136. f. 1. 4. 
2. limbiferum Blanf. — Conch. Ind. VII. t. 136. f. 2. 3. 
Obs. His proximum Cyathopoma  seticinclum  Bedd. 
A hhiostoma Benson. 
(p. 46.) 
4. Haughtoni Bens. — JPrerocyclos Haughtoni (Rhiostoma) Hanl. 4 TAeob. 
Conch. Ind. I. t. 5. f. 10. 
XI. Spiraculum Pearson. 
(p. 4.) 
l. hispidum Pears. — Prerocyclos hispidus Hanl. & Theob. Conch. Ind. 
Liu. 4. 
