246 



SCIENCE-GOSSIP. 



descending a little obliquely posteriorly, strongly 

 indented in the middle ; sixthly, two short, stout, 

 slightly oblique folds, the posterior a little 

 higher than the anterior one ; seventhly, a 

 short and thinner horizontal fold near the 

 lower suture, with an elongated tooth a little 

 above (see fig. 36^, which shows the inside of the 

 outer wall with its palatal folds). The large form 

 of this species, which is regarded as the type, I have 

 been unable to obtain ; it is said to measure 32 

 millimetres in diameter, and to show all the palatal 

 folds through the shell- wall. A small variety, 

 stated by Dr. Pfeiffer not to show the palatal folds 

 externally, measures 21 millimetres. The specimen 

 figured, which is from Louang Prabang, Laos, 

 measures 19 millimetres in diameter, and does not 

 show the folds through the shell ; it is in Mr. 

 Ponsonby's collection. A specimen in my collec- 

 tion, however, measuring 21 millimetres, distinctly 

 shows the folds through the shell-wall. 



Pledopylis brachyplecta (figs. 37a-/), from Moul- 

 main, was described by Mr. Benson in the "Annals 

 and Magazine of Natural History," (3), xi. (1863), 

 p, 319, and figured in Hanley and Theobald's 

 •'ConchologiaIndica,"t.57,ff. 7 and 10(1870). The 

 armature was figured by Lieut. -Colonel Godwin- 

 Austen in the " Proceedings of the Zoological 

 Society, 1874, t. 74, f. 8. The shell is disk-shaped, 

 widely umbilicated, dull-reddish chestnut, with 



--^"-'^Wru!- 



c d e 



Fig- 37.—Plccfopylis brachyplecta. 



amber-coloured apex, paler below, finely and 

 regularly ribbed, and decussated by minute spiral 

 sculpture. It is composed of six or six and a-half 

 more or less convex whorls, which increase slowly, 

 the last being rounded and subangulated above, 

 near the suture, and shortly and abruptly descend- 

 ing in front. The aperture is ear-shaped, and the 

 peristome brown, strongly thickened and a little 

 reflexed, its slightly converging margins being 

 joined by a thickened curved ridge, which 

 is slightly notched at the junctions above and 

 below. A strong entering flexuous fold is given 

 off from the parietal ridge, revolving over 



less than a quarter of a whorl. The parietal 

 armature further consists of two strong, vertical, 

 slightly curved parallel plates ; the anterior one 

 has a short horizontal support posteriorly below, 

 and a strong horizontal ridge anteriorly above; 

 the posterior one gives off on the posterior side two 

 short supports, one above and one below. A short, 

 free horizontal fold occurs below the vertical 

 plates. Fig. 37^^ shows the parietal wall with its 

 plates and the fold, while fig. 37/ gives the anterior 

 view of both parietal and palatal armatures. The 

 palatal armature consists of; first, a thin horizontal 

 fold near the suture ; next, four short, broad, oblique, 

 nearly parallel folds, whose lower concave sides 

 face the aperture ; finally, a short thin horizontal 

 fold near the lower suture. A little above the 

 second fold and united to its posterior extremity 

 occurs a very short straight fold, while another 

 short, slight oblique fold is found between the 

 posterior ends of the fifth and sixth folds. (See 

 fig. 37^, which shows the inside of the outer wall 

 with its palatal folds.) Figs. 37^-/ are drawn 

 from one of the type specimens from Moulmain 

 in the McAndrew collection of the University 

 Museum of Zoology, Cambridge, the shells having 

 been lent for this purpose by Mr. S. F. Harmer, 

 the Superintendent. It measures — major diameter, 

 22 millimetres ; minor diameter, 18 millimetres ; 

 axis, 8 millimetres. Among the shells of the genus 

 Pledopylis in the British Museum, I found two 

 specimens in the Theobald collection, labelled 

 Pledopylis dathratula, Benson, from Balcadua, 

 Ceylon. I am not aware that Mr. Benson ever 

 published this name, but Dr. Pfeiffer described a 

 species belonging to a different section of the 

 genus, from Ceylon, under that name. As no 

 species of the section to which these three shells 

 belong has ever been found in Ceylon, it is 

 probable that there is a mistake in the locality, 

 and it is certain that the name is wrong. 

 Judging from the external resemblances to Plec- 

 topylis hrachypleda, I suspected that these shells 

 would prove to pertain to that species, and 

 having obtained permission from Mr. Edgar Smith, 

 the Assistant Keeper, to open one of the shells, I 

 was enabled to confirm my suspicion, for the 

 armature proved to be identical with that of P. 

 hrachypleda. One of these specimens is shown in 

 three different positions in figs. 37a-f . It measures — 

 major diameter, 22 millimetres ; minor diameter, 

 18-5 millimetres; axis, 8 millimetres. 



(To be continued.) 



Errata. — Lieut.-Colonel Godwin Austen has kindly drawn 

 my attention to the following errors : p. 205, second column, 

 fifth line from top, for Henozdan, read hTengdan ; eighth line 

 from top, for Kopameda, read Kopamedza. He also states 

 that the locality given for Mr. Ponsonby's specimen of 

 Plectopylis serica, Sylhet, is impossible, as these species are 

 very local, and one found on the summit of a range of 5,000 

 feet and upwards is not likely to occur in a country like 

 Sylhet, only just above the level of the sea. 



