PLECTOPYLIS. 131 



Plectopylis cyclaspis, Stoliczka, J. A. S. B. xl, 1871. p. 222, pi. 15, 



Plectopylis (s. s.) cyclaspis, Glide, op. cit. vi, 1899, p. 148. 

 Helix revoluta, Pfeiffer, Malak. Blatt. xiv, 1867, p. 64. 



Original description : " Testa sinistrorsa, late umbilicata, 

 lenticulari-depressa, laevigata, superne demum oblique rugata, 

 ftiscescente ; spira depresse conoidea, apice obtuso, sutura 

 marginata ; anfractibus 7| lente crescentibus, superne planulatls, 

 ultimo non descendente, acute cariuato, carina corupressiuscula, 

 basi convexa, circa umbilicum profundum perspectivum sub- 

 angulata; apertura perobliqua, rotundato-lunari, peristomate 

 expanse, reflexo, superne prope carinam proininente, angulato, 

 marginibus lamina valde elevata lamellam breviter intrantem 

 emittente junctis. 



"Diam. maj. 18, minor 16, axis 6^ millim." (Benson.) 



Hob. Burma: Moulmain (Theobald, Stoliczka); Damsang and 

 E/issom Peak (Godwin- Austen). 



A well defined species which may at once be separated from 

 all its congeners by the keeled periphery. Helix revoluta was 

 described by Pfeiffer as from the Andaman Islands. Unfortu- 

 nately, I have been unsuccessful in tracing the whereabouts of the 

 specimens from which the diagnosis was drawn up, as Mr. Smith, 

 who kindly searched the collection in the British Museum, has 

 been unable to find them there ; and the late Professor Boettger 

 informed me that they are nob in the Pfeiffer collection acquired 



Fig. 65. Plectopylis cyclaspis. 



by Dr. Dohrn. This is all the more to be regretted as no Plecto- 

 pylis has since been discovered in the Andaman Islands. The 

 late Mr. Stoliczka (J. A S. B. xl, 1871, p. 223) was of opinion that 

 this shell could hardly be distinct from Plectopylis cyclaspis, his 

 specimens of which agreed perfectly with the measurements given 

 by Dr. Pfeiffer. He adds that amongst many thousands of shells 

 from the Andaman Islands, he never received P. cyclaspis and h& 



K2 



