498 DR G. S. BRADY ON 



truncated, rounded off below, but forming an obtuse angle at its junction with the dorsal 

 margin. Dorsal margin prominent over the anterior hinge, thence sloping with a slight 

 outward curve to the posterior extremity, in front of which it is slightly emarginate ; 

 ventral margin gently sinuated in the middle. Seen from above, ovate, more than twice 

 as long as broad, circumference irregularly crenated or emarginate, sides subparallel, 

 extremities obtusely rounded, but not at all truncated, the posterior considerably the wider 

 of the two. Surface marked with undulated ridges very variable in their development 

 (but towards the posterior extremity disposed more or less transversely), and enclosing 

 between them fossae of irregular shape and size. Length '5 mm. 



Habitat. — Noumea, shore-sand, also dredged in 2-6 fathoms ; Suva reef, Levuka, 

 between tide-marks , Sava-Sava-Bay, Vanua Levu, 4 fathoms ; Eambe Island, between 

 tide marks ; Apia, Upolu, reef and shore-pools ; Mango Island, on fringing reef. 



The specimens referred in the " Challenger " Eeport to Cythere crispata are undoubtedly 

 identical with those here described, and bear certainly a very close resemblance to the 

 European species Cythere crispata, but after examining minutely the large series of 

 specimens found in these gatherings from Fiji and New Caledonia, I no longer think that 

 they are properly referable to that species. The outline of the northern form is more 

 flexuous, the ribs generally fewer and more prominent and enclosing larger hollows, and 

 viewed dorsally the posterior extremity is distinctly truncated. Individual specimens, 

 however, vary very greatly, and it is by no means easy to assign distinct limits to the 

 three species crispata, crenata and canaliculata. 



Cythere ochracea, n. sp. (PL II. figs. 8, 9). 



Shell, seen from the side, elongated, subsigmoid, greatest height in the middle, and 

 equal to less than half the length. Anterior extremity evenly rounded, posterior rounded off 

 below, and obscurely angulated above at its dorsal termination ; dorsal margin gently and 

 evenly arcuate, ventral incurved for the greater part of its length, slightly convex behind. 

 Seen from above, the outline is elongated, hastate, widest near the posterior extremity, 

 width and height equal ; from the widest point the sides approximate with a gentle curve 

 to the front, which is attenuated and acute, while behind they converge suddenly with a 

 slight sinuation, terminating in a subacute, slightly produced angle. Surface rather coarsely 

 pitted, the hollows running together so as to form flexuous grooves, which run mostly in 

 an oblique direction, except on the anterior portion of the valve, where they are more or 

 less distinctly concentric. In young adults the pitting is the most conspicuous feature, 

 but in older specimens this gives place largely to the grooved sculpture. Colour 

 yellowish-brown. Length *5 mm. 



Habitat. — Noumea; in shore-sand from Porcheron's Beach, and Artillery Point. 



Cythere injiata, n. sp. (PL II. figs. 3-5). 



Shell, seen from the side, oblong, slightly flexed, greatest height situated near the 

 front, and equal to half the length. Anterior extremity rounded, produced slightly below 



