218 PROCKEDINGS OP THE MALACOLOGICAL SOCIETY. 



posterior plate curved, obliquely descending backwards, with a short 

 support posteriorly above. 



Palatal armature consisting of six short and thin folds, the first five 

 nearly horizontal, the sixth oblique, the first and sixth free, the other 

 four united by a transverse ridge, which projects above the second 

 fold curving forward, and below the fifth curving backwards, then 

 shortly upwards. Diam. maj. 9-5, min. 8 mm. ; alt. 4 mm. 



Hob. — Muong-Kong. Type in my collection. 



This species is allied to P. Mansuyi, but, although having half a whorl 

 less, it is larger; it is also more depressed in the spire, is smoother, 

 the last whorl is scarcely deflexed in front, the parietal ridge at the 

 aperture is not raised and is without entering fold. P. Mansuyi, 

 moreover, lacks the supports at both extremities of the anterior 

 parietal plate, and the present species has the four inner palatal folds 

 horizontal instead of oblique, and lacks the posterior row of denticles 

 found in its ally. 



EXPLANATION OF PLATE IX. 



Fig. 









1. 



Plectopylis Gouldingi, n.sp., shell. 





Iff. 





,, parietal armature. 





u. 





,, palatal ,, 





2. 





anterides, n.sp., shell. 





2«. 





, , parietal armature. 





2b. 





,, palatal ,, 





3. 





if esi-rtym, n.sp., shell. 





3ff. 





,, parietal armature. 





U. 





, , palatal , , 





4. 





verecunda, n.sp., shell. 





4r/. 





,, parietal armature. 





46. 





, , palatal , , 





5. 





cyrtochila, n.sp., shell. 





5rt. 





,, parietal armature. 





5b. 





, , palatal , , 





6. 





fallax, n.sp., shell. 





6«. 





,, parietal armature. 





U. 





,, palatal ,, 





N.B. — By an oversig 



ht the 



posterior parietal plate has been omitted in fig. 



Off, 



while in fig. 5b the first 



palatal 



fold is shown erroneously as a denticle. 





