94 THE VOYAGE OF H.M.S. CHALLENGER. 



Cythere viminea, n. sp. (PI. XVIII. fig. 3, a-c). 



Valves, seen laterally, oblong, subovate, greatest height situated near the anterior 

 extremity and equal to nearly two-thirds of the length ; extremities well rounded and 

 fringed below the middle with a series of six or eight small but stout spines ; dorsal 

 margin sloping gently from before backwards, and slightly sinuated, ventral nearly 

 straight ; seen from above, the lateral margin is angular, nearly straight in the middle, 

 then sloping suddenly to either end, the extremities forming broad truncated projections. 

 Shell sculptured with closely-set polygonal fossse, and produced round the margins so as 

 to form a stout encircling flange. Length, l-38th of an inch ('66 mm.). 



One valve dredged in 1375 fathoms, lat. 46° 46' S., long. 45° 31' E. {Station 146). 



[PI. XVIII. fig. 3, a-c. a Right valve seen from side, h from above, c from front. 

 Magnified 50 diametei'S.] 



58. Cythere lepralioides, n. sp. (PI. XIX. fig. 5, a-d). 



Carapace oblong, subovate, tumid, seen from the side, rather higher in front than 

 behind, the height being about equal to half the length ; anterior extremity obliquely 

 rounded and bordered by even lines of short bhmt teeth ; posterior extremity narrowed, 

 unevenly notched ; dorsal margin gibbous in front over' the hinge-tubercle, thence 

 sloping gently backwards ; ventral margin slightly convex ; seen from above, the shell 

 is oblong-ovate, twice as long as broad, widest behind the middle, lateral margins evenly 

 convex, extremities obtuse and emarginate ; end view very broadly ovate. Surface of the 

 shell marked with closely-packed, large angular excavations and depressed on the dorsal 

 and ventral surfaces along the lines of contact of the valves. Length, l-32d of an inch 

 (775 mm.). 



Dredged at Simon's Bay, South Africa (Station 140), in a depth of 15 to 20 fathoms, 

 and off' the Cape of Good Hope (Station 142) in 150 fathoms. 



[PL XIX. fig. 5, a-d. a Shell seen from left side, h from above, c from below, d 

 from front. Magnified 50 diameters.] 



59. Cythere hodgii, G. S. Brady (PI. XXV. fig. 1, a-d). 



Cythere hodgii, Brady, Trans. ZooL Soc. (1865), vol. v. p. 373, pL lix. fig. 3, a, h. 



Carapace of the female oblong-ovate ; seen from the side, subovate or subrhomboidal, 

 scarcely higher in front than behind, height equal to somewhat more than half the 

 length ; extremities obliquely rounded, the anterior bearing on the lower half of each 

 valve a variable number (3 to 8) of short downward-pointing spines, the posterior one a 

 much larger spine, which also points obliquely downwards (sometimes there are one or two 

 supplementary small spines) ; seen from above, the outline is regularly ovate, widest near 

 the middle, about twice as long as broad, somewhat rnore tapered in front than behind, 



