442 DE. G. S. BEADY ON NEW OE 



Xestoleberis olivacea, sp. n. (Plate XLVI. figs. 6, 7.) 



Shell, seen from the side (fig. 6), subreniform, greatest height situated in the middle 

 and equal to two-thirds of the length ; extremities well rounded ; dorsal margin boldly 

 and evenly arched, sloping steeply behind, more gradually in front, ventral rather 

 deeply sinuated in front, boldly arcuate behind, where it forms a curve continuous 

 with that of the posterior extremity ; seen from above (fig. 7), ovate, nearly twice as 

 long as broad, widest in the middle, lateral margins evenly and boldly arcuate ; 

 anterior extremity subacuminate, posterior narrowly rounded. Shell-surface perfectly 

 smooth and without markings, excepting a dark eye-spot. Colour dark olive. Length 

 •55 mm. 



Hah. Rock-pools, Brighton, New Zealand. 



Xestoleberis compressa, sp. n. (Plate XLVI. figs. 10-19.) 



Shell, seen from the side (fig. 10), reniform, highest in the middle, height equal to 

 more than half the length ; anterior extremity obliquely rounded, posterior boldly and 

 evenly rounded; dorsal margin boldly arched, ventral rather deeply sinuated in the 

 middle ; seen from above (fig. 11), compressed, ovate, fully twice as long as broad, 

 acuminate in front, rounded behind. Shell-surface smooth, marked with distant, very 

 minute papilla?. Colour yellowish. Length - 46 mm. Antennules (fig. 13) six-jointed, 

 third, fourth, and fifth joints each with a single strong apical spine and a slender seta, 

 sixth joint with two setse ; second joint fringed externally with fine, short hairs ; in 

 other respects like typical Xestoleberis. 



Hah. Pock-pools, Brighton, New Zealand. - 



G. W. Miiller notes that in many, if not in all, species of Xestoleberis the shell bears 

 a crescentic pellucid patch behind the eyes, and of this he gives several figures. I 

 have not been able to find this patch in any of the species here described, though in 

 X. compressa there is, at any rate in some specimens (fig. 10), a similar mark in front 

 of the eyes. But the shell in this species and in others of the same genus is liable to 

 the presence of similar irregular spots on various parts. 



Genus Cythere O. F. Miiller. 

 Ctthere brunnea, sp. n. (Plate XLVII. figs. 8-15.) 



Male. Shell, seen from the side (fig. 8), subreniform, greatest height in front of the 

 middle, and equal to more than half the length ; anterior extremity wide, rather 

 obliquely rounded, forming a very wide band or fillet, which ceases above at the 

 highest point of the valve, but is continued in a narrower form along the ventral 

 margin, and as far as the postero-dorsal angle ; posterior extremity much narrower 

 than the anterior, subtruncate, rounded off below, almost angular above ; dorsal 

 margin slightly arcuate, sloping continuously and evenly from the front backward; 



