PTEROCYCLOS §. 1. 41 



Plerocticlos Bernardii Reei^e Conch. ic. sp. 23. t. 5. 

 Habitat Siam. 



IV. Pterocyclos Benson. 



Pfr. Mon. Pneum. p. 41. Suppl. p. 28. — Animal speciei 

 haud nominatae ab A. Adams in Ann. and Mag. nat. hist. 

 3 d. scr. Vll. 1861. p. 196 descriptum invenies. — Conf, 

 W. T. Blanford in Ann. and Mag. nat. hist. Jun, 1864. 



Conspectus specierum. 



A. Aberrantes §. 1. Nr. 1 — 4. 



B. Normales. 



a. Anfractu ultimo spiraculo munito §. 2. Nr. 5. 



b, Spiraculo nuUo . . . , . . §. 3. Nr. 6—17. 



C. Species vix notae ......§. 4. Nr. 18 — 19. 



§. 1. 



1. tenuilabiatus Metc. (Coll. 47. — Reevet.l. 220. 



f. 5. — Borneo.) , . Pneum. II. p. 18. 



2. Pt. liabuaaieiiMii^ Pfr> 221. 



T. late umbilicata, subdiscoidea, solida, subtilissime stria- 

 tula, sordide flavida unicolor vel in anfractibus superioribus 

 castaneo distanter flammulata ; spira vix elevata, vertice corneo 

 submucronato ; anfr. 41/2 convexiusculi , rapide accrescentes, 

 ultimus subdepresse rotundatus, non descendens ; apertura fere 

 diagonalis, circularis ; perist. duplex : internum porrectum, 

 superne leviter incisum , externura latere sinistro reflexum, 

 dextro sublate patens, superne cucullatim dilatatum et sub- 

 deflexum. — Operc. planiusculum, calcareum, marginibus 

 anfractuum infundibuliformiter elevatis. — Diam. maj. 18, 

 min. 14, alt. 5 mill. Apert. diam. 5 mill. (Coll. Nr. 48.) 

 Pterocyclos Lahuanensis Pfr. in Proc. Zool. Soc. 1863. 

 Habitat in insula Labuan (Ilugh Low). 



3. Pt. liowianus Pfr. 222 



T. late umbilicata, subdiscoidea, tenuiuscula, subtiliter 

 striatula, sericina, fulva, flammis saturate castaneis amoene 



