1891.] LAND-SHELLS FROM BORNEO. 33 



It would be difficult to select two shells differing so much in form 

 as D. Imgonis and D. nasuta ; any classiUcation based on sbell- 

 characters would jdMce them widely apart, yet the animals as regards 

 their structure are closely allied. This points to a long occupation 

 of this island by this group of land-shells. 



Dyakia moluensis, n. sp. (Plate II. fig. 6.) 



Shell sinistral, depressedly pyramidal, not perforate, solid, rounded 

 below, sharply keeled ; sculpture, irregular furrowing, crossed by 

 rough transverse curvilinear and broken granulation ; colour dark 

 chestnut-brown, with a lemon-yellow narrow line on the periphery 

 and also running with the suture, a circle of same colour around the 

 umbilicus ; spire low, sides flat ; apex blunt ; suture linear : whorls 

 5, gradually increasing, flat-sided ; aperture semi-lunate, very 

 oblique; peristome thickened below, with a slightly sinuate margin 

 above ; columellar margin oblique. 



Size : maj. diam. 28"0, min. 24*8 ; alt. axis 9*3 millim. 



Hub. Molu Hills {A. Everett). 



Only one specimen was sent home of this very pretty shell, 

 which is somewhat like the dextral H. albula from Moti Island, one 

 of the Ternate group. 



EvERETTiA, subgen. nov. (Plate III.) 

 (Type, Macrochlamys jucunda.) 



The animal from a spirit- specimen is pale ochre in colour, with jet- 

 black tentacles and a black band on either side of the neck from the 

 base of the tentacles running backwards. 



The pallial margin (fig. 5) is broad, the foot below with a central 

 ambulatory area. The mucous gland (fig. .t a) is large, and in life the 

 extremity of the foot is apparently much pointed and overhanging. 

 There are no linguiform shell-lobes either on the right or left side, 

 but on the latter the lobe is a simple baud turned back over the edge 

 of the peristome ; both the right and left neck-lobes are very small. 



The generative organs (tig. 6) are very peculiar and unlike those 

 of any species I have examined or that I find figured by Professor 

 Semper. The principal difl^erence lies in the amatorial organ or 

 dart-sac ; this is cylindrical below as in other genera, but at the 

 inner extremity terminates in a fringe of very numerous accessory 

 glands (fig. 6 a), very nearly equal in length to the solid fleshy lower 

 portion. These fringe-like glands are finely pointed and lie buried in 

 a mass of mucous glands having a segmented structure, each separate 

 lobe being associated with one of the accessory glands. The lower end 

 is armed with a stout and solid calcareous dart (Liebespiel), having a 

 conical attachment to the muscular portion (fig. 6 b). The penis has 

 no kale-sac. The albumen-gland is very large. 



The odontophore : — The rows of teeth, about 90, gradually de- 

 crease to the outer margin, the formula being 



30. 26. 1. 26. 30. 

 56. 1. .56. 

 Proc. Zool. Soc— 1891, No. III. 3 



