PTEROC YCLOS 



Plate II. 



Species 6. (Pig. «, h, Mus. Cuming.) 



Pterocyclos Batciiianensis. Fler. testa perampUter 

 aperte umbiUcald, siMlscokled, fiilvo-casfaneo tincld 

 et undatd, anfractilms rotmidatis, dense slriatis, su- 

 periie obscure spiraUter liratis et malkatis ; nperturd 

 paniusculd, sbm sitblate dilatata. 



The Batchian Pterocyclos. Shell very largely openly 

 umbilicated, subdiseoid, stained and waved witli ful- 

 vous chestnut, whorls rounded, closely striated, spi- 

 rally obscurely ridged and malleated at the \ippcr 

 part ; apei-ture rather small, sinus rather broadly di- 

 lated. 



Pfeiffek, MS. in Mus. Cuming. 



Hab. Isle of Batchian. 



The whorls in this species present indications of spiral 

 equidistant ridges on the upper part. 



Species 7. (Fig. a, b, Mus. Cuming.) 



Pterocyclos Blaxdi. Pter. testd subampJHer aperte 

 nmbillcatd, subdiscoided,fidvo-castaiieo obUqiie strigutd 

 et variegntd, infra peripheriam angiiste fasciaid, ati- 

 fractibus ad suturas impressis, rude striatis ; apertiii-d 

 oblique circulari, labro crasse refexo, dnplicato, sinit 

 flexuose auricido-dilatato. 



Bland's Pterocyclos. Shell rather largely openly um- 

 bilicated, somewhat discoid, obliquely streaked and 

 variegated with fulvous chestnut, narrowly banded 

 below the periphery, whorls impressed at the sutures, 

 rudely striated; aperture obliquely circular, lip thickly 

 reflected, duplicate, sinus flexuously auricidarly di- 

 lated. 



Benson, Ann. Nat. Hist. ser. 2. vol. viii. p. 5. f. 1. 



Hab. Island of Pulo Susson, near Pulo Pcnan^-. 



I have no authority for regarding this shell as P. Blaudi 

 beyond the circumstance of its differing from the other 

 described species of the genus, and agreeing pretty nearly 

 with Mr. Benson's outline figure. 



Species 8. (Fig. a, b, Mus. Benson.) 

 Pterocyclos rupestris. Pter. testd latissimi per- 



aperte umbilicatd, anguste discoided, iistidato-fusro 

 iinctd et obscure fasciatd, anfractilms rotmidatis^ nd 

 snturas lineari-impressis, deinde plicato-striatis -. nper- 

 turd oblique circidarl, sinu tumido el anricnlnto-mn- 

 torto, margine hiferiore ad extremilaiem nncintito. 



The KocK-iNHABiTiNG Pterocyclos. Shell very 

 broadly, very openly umbilicated, narrowly discoid, 

 stained and obscurely banded with l)urnt brown, 

 whorls rounded, linearly impressed at the sutures, 

 then plicately striated, apertm-e obliquely circular, 

 simis swollen and auricularly twisted, lower luaroin 

 hooked at the extremity. 



Benson, Journ. Asiat. Soe. 1832, p. 11. pi. 2. 

 Pterocyclos pictns, Ti-oschel. 

 Steganotoma picttm, Troschel. 

 Cgcloslonia pictum. Petit. 



Hab. Cuttack, India. 



The sinus in this very interesting species is tuniidlv 

 auricularly contorted on the body whorl, and the lower 

 margin curls into it at its extremity in the form ol' a 

 sharp involute hook. 



Species 9. (Fig. a,b, jMus. Cuming.) 



Pterocyclos Albersi. Pter. testd ampliter aperte u,n- 

 bdicatd, snhdiscoided, fiilcd, castaneo undatd, infra 

 peripheriam et circa nmbilicum latifasciald, anfrac- 

 tibus rotnndatis, ad suturas plicato-marginaiis, deinde 

 rude striatis; apertnrd parviusculd, sinu flexnoso-nu- 

 riculato, margine dilatato descendente. 



Albers' Pterocyclos. Shell largely openly umbilicated, 

 subdiseoid, fulvous, waved with chestnut, broadly 

 banded below the periphery and around tli(^ umbili- 

 cus, whorls rounded, plicately margined at the sutures, 

 then rudely striated, aperture rather small, sinus flex- 

 uously auriculated, the dilated margin descending. 



Pfeiffer, Zeitschr. fur Malak. lS-17, p. 1,51. 

 Cijclostoma Albersi, Petit. 



Hab. Khasia Hills, India. 



Encircled with two characteristic dark bands. At the 

 aperture the dilated wing-like process descends forward 

 over the sinus. 



Februarv. 1SG3. 



