Mr. W. H. Benson on Plectopylis. 245 



The 3rd section is distinguished by having the epiphragm 

 near the aperture, and by a still more simple parietal lamina 

 placed vertically, and with a separate horizontal plica below, 

 as in the previous sections, but unfurnished with anterior 

 lamellae. The palatal plica; are six in number, several are backed 

 by a second more oblique row, and the vertical lamina present 

 in the first section is deficient. It comprehends 



Helix pledostoma, B. 

 ■ Pinacis, B. 



The pylaic plicse may be distinctly viewed by filing across the 

 last whorl, a little in front of the barrier, so as not to injure the 

 palatal plicse nor the aperture of the shell, care being taken first 

 to ascertain the distance from the aperture by means of a flexible 

 lamina of quill. The slit may be cautiously enlarged, according 

 to circumstances, and the back of the epiphragm may be exa- 

 mined by a similar process beyond it. 



The following characters require to be added to those hitherto 

 recorded : — 



1. Helix Achatina, Gray. 



Janua pliciformi fauciali prima remota, lamina 1 parietali magna 

 verticali bifurcata, postice sinuosa intrante, antice lamellas 2 emit- 

 tente, mediana aperturam attingeute, iuferiore mediocri, plica 1 

 basali horizontali elongata ; plicis palatalibus 3 superioribus, 1 

 basali intrantibus, lamina 1 verticali lata elongata intersita. 



The pylae or barriers are reproduced at certain distances in the 

 interior whorls ; and the more distant have only a short central 

 lamella, occasionally obsolete, proceeding anteriorly from the 

 parietal lamina, in addition to the basal plica. 



Found at the Farm Caves near Moulmein. 



2. Helix Cyclasjns, B. 



(Annals Nat. Hist. March and April, 1859.) 



Janua pliciformi fauciali prima rernota, lamina 1 parietali magna 

 obliqua subbifurcata, antice lamellani unicani inferiorem brcvem 

 emittente, plica 1 basali spirali ; plicis 3 j)alatalibus superioribus 

 fortibus elongatis sinuosis, 1 basali intrantibus, lamina 1 obliqua 

 satis magna intersita. 



In this shell the large parietal lamina is not so distinctly and 

 widely double as in H. Achatina, and it gives ofi" no medial 

 anterior lamella to connect it with the shortened apertural 

 lamella. 



Mr. Theobald's single specimen was much worn. Examples 

 in good condition, procured by Capt. J. C. Haughton at the 



