112 Messrs. J. E. Cooper and JEL B. Preston on 



the lip above; labrura acute, simple; aperture subcircular ; 

 interior of shell iridescent. 



Alt. 10, diam. maj. 12, diam. min. 10 mm. 



Aperture : alt. 6, diam. 5*5 mm. 



Hab. Falkland Islands. 



Allied to P. vio/acea, King, but much more solid and 

 globose in form; the iridescence of the shell is only visible 

 when the thick coloured outer layer is chipped away. 



Immature specimens have a very narrow oblique umbilicus, 

 which becomes closed in the adult, leaving only the shallow 

 depression mentioned above. 



Photinula tamiata, King, var. nivea, no v. 



Shell smaller than the typical form, pure white, exhibiting 

 faint traces of narrow spiral banding. 



Alt. 14*25, diam. maj. 18, diam. min. 14*25 mm. 

 Aperture : alt. 8*5, diam. 8 mm. 

 Hab. Falkland Islands. 



Modiolarca gemma, sp. n. (Fig. 4.) 



Shell irregularly oblong, somewhat polished reddish brown, 

 marked witti rather coarse concentric lines of growth ; urn- 

 bones anteriorly situate, neither large nor prominent ; dorsal 

 margin scarcely arched, slightly sloping; ventral margin 

 gently rounded ; anterior side rather angularly rounded ; 

 posterior margin descending abruptly. 



Long. 1-75, lat. 2'75 mm. 



Hab. Falkland Islands. 



Modiolarca picturata, sp. n. (Fig. 5.) 



Shell trapezoidal, somewhat shining, dark olive-green 

 painted with narrow, radiate, transverse bands of reddish 

 purple, and spotted, especially above, with irregular, round, 

 yellowish markings, sculptured with concentric lines of 

 growth; umbones rather large and prominent, dark purple; 

 anterior side descending abruptly ; posterior side produced, 

 bluntly rounded; dorsal margin scarcely arched; ventral 

 margin anteriorly slightly excavated, posteriorly rounded ; 

 interior of shell shining, dark purple throughout. 



Long. 3, lat. 4*5 mm. 



Hab. Falkland Islands. 



Cyamium iridescens, sp. n. (Fig. 6.) 



Shell elongately oblong, iridescent, white, shining, finely 

 concentrically striate, bearing on the posterior side of either 



