232 



SCIENCE-GOSSIP. 



obligingly placed in my hands by Miss Linter, at parietal and palatal armatures from the posterior 



whose request I name it after her friend, Mrs. 



6y.~Plectopylis pen'icrai 



Lumley Perrier. In contour this new species 

 resembles Plectopylis perarcta (ante vol. iii. page 155, 

 fig. 19), but the shell is much larger. The 

 parietal armature further connects it with the 

 species just named, but the palatal armature is 

 more like that of P. kiophis. The two specimens 

 of the new species are stated by Miss Linter to be 

 from Thayet-Mayo, Pegu, Burma ; a third specimen, 

 which is in Miss Linter's collection, is accom- 

 panied by a label bearing the locality, Niningo 

 (Burma ?), but I have failed to trace this name in any 

 of the maps and gazetteers to which I have access. 

 The specimen figured, and the one in Miss 

 Linter's collection, have the measurements given 

 in the diagnosis, but my second specimen measures 

 only 12 5 millimetres in diameter. Figs. 6'ja-c 

 show the shell in three different aspects, natural 

 size ; figs. 67^-/, are enlarged ; d, shows the 



and round the umbilicus, and descending shortly and 

 abruptly in front. Aperture heart-shaped ; peristome white, 

 scarcely thickened, a little reflected; the margins united by 

 an elevated sinuous ridge on the parietal callus, notched at 

 the lower junction. Umbilicus wide and deep. Parietal 

 wall with a thin vertical plate, strongly deflected posteriorly 

 below, and giving oft a short horizontal ridge at the upper 

 extremity on each side ; a long horizontal flexuous fold 

 rises close to the upper extremity of this plate on the anterior 

 side, descending suddenly at first, then ascending gradually, 

 and afterwards gradually descending, following the deflection 

 of the last whorl, becoming united to the ridge at the 

 aperture ; a second, shorter, horizontal fold occurs below 

 this one, rising close to the lower extremity of the vertical 

 plate, proceedmg horizontally at first, and then ascending a 

 little ; another very thin fold rises below the vertical plate, 

 running parallel to the lower suture as far as the aperture, 

 where it unites with the ridge. Palatal folds, five : the first, 

 rather long and thin, near to and parallel with the suture, 

 with a deep indentation near the posterior extremity, divid- 

 ing it into two unequal parts; the second, horizontal, a 

 little deflected posteriorly, with an elongated denticle 

 posteriorly, an 1 a second, smaller, one above the first ; the 

 third fold much shorter, strongly curved downwards 

 posteriorly, with a minute denticle posteriorly; the foiirth 

 fold vertical with an obliquely descending ridge posteriorly 

 at the upper extremity, and bifurcated at the louer extremity, 

 the anterior aim of the bifurcation the shorter; a minute 

 denticle occurs near the ridge at the upper extremity and a 

 second one near the middle, both on the posterior side ; the 

 fifth fold is thin, horizontal, and strongly deflected on both 

 sides. — Major diameter, 15 millimetres; minor diameter, 

 12 milliuietres ; altitude, 5 millimetres. — Habitat, Thayet- 

 Mayo, Pegu, Burma. — Type in my collection. 



side ; e, the inside of the outer wall with the 

 palatal folds and denticles ; and /, the parietal 

 wall with its plate and folds. 



(To be continued.) 



