A MONOGRAPn OF THE PILL-.VTLLIPEDES. 271 



Vulva like that of Z. hrandti. 



Length about 19 mm. 



Locality. — Ceylon {R. Templeton], 



This species differs from all yet kno^^•n in the spinous character of 

 its legs — a character overlooked by Mr. Butler in bis descrij)tion of the 

 type specimen. 



Arth^osphcEra notkeps (Butler). (PI. B, figs. 2-2a.) 



Syn. Zephroma notkeps, Butler, Ann. N. H. (4), X, p. 355 (1872) ; 

 id., ProG. Zool. Soc. Lend., 1873, p. 179, pi. xix, fig. 4. 



Colour pale brownish-green. 



Head shining, punctured somewhat sparsely, armed with about 

 three teeth on each side ; the ridge that bears these teeth not continu- 

 ous across the head, but divided in the middle line by a wide excava- 

 tion. 



Nuchal-plate sparsel}' punctured ; inferior border strongly sinnate 

 and with upturned margin ; not marked with a fine groove or fine 

 ridge. 



27id tergite thickly and very finely punctured, dull ; in front 

 smooth and shining ; marked close before its front margin with a 

 very faint sulcus, gently rounded off in front and with slightly up- 

 turned edge ; anterior border evenly rounded from above downwards ; 

 the lamina very slightly developed and with thickened margin ; 

 the infei'ior portion of the tergite, above the base of the lamina, faintly 

 ridged. 



TergHes thickly and very finely punctured throughout. 



Anal tergite ( 9 ) rounded from above downwards and from side to 

 side ; punctured like the rest ; furnished below in front on its inner 

 surface with a distincL black ridge, behind and below which the edge 

 of the tergite distinctly notched. 



Vtdva mucb more quadrate and less elongate than in A. heterostida, 

 more resembling that of A . versicolor, but less oval. 



Locality. — Ceylon, A single female example without history. 



Length about 20 ram. 



This species resembles Z. versicolor in the sinuate inferior border of 

 the nuchal-plate ; but it may easily be distinguished by the evenly 

 arched anterior edge of the first tergite, and by the difference in colour, 

 A, versicolor being beautifully marbled with yellow and black. 



