REPORT ON THE OSTRACODA. 139 



lateral surface of the shell is thickly beset with subangular excavations, and the ventral 

 surface is longitudinally furrowed. Length, l-35th of an inch ('75 mm.). 



Found off Christmas Harbom-, Kerguelen Island, in a depth of 120 fathoms (Station 

 149), and off Heard Island in 75 fathoms (Station 151). 



Though bearing considerable resemblance to the northern species Cytheropteron 

 latissimum (Norman), this is easily distinguished by the character of the sm-face- 

 sculpture, which shows no tendency to run into transverse grooves ; the lateral alse, too, 

 are considerably more prominent. 



[PI. XXXIV. fig. 2, a-d. a Shell seen from left side, b from above, c from below, 

 d from front. All magnified 50 diameters.] 



7. Cytheropteron iKitagoniense, n. sp. (PI. XXXIII. fig. 7, a-d). 



Carapace tumid ; seen from the side, irregularly rhomboidal, highest a little in front 

 of the middle, height equal to two-thirds of the length, anterior extremity scarcely 

 rounded, depressed, posterior produced in the middle into a narrow truncated beak ; 

 dorsal margin high in the middle, irregularly angular, sloping steeply toward the front, 

 but more gently behind, ventral slightly protuberant behind the middle ; seen from 

 above, the outline is broadly ovate, widest near the middle, width about ec^ual to the 

 height, extremities obtusely pointed ; seen endwise, the outline is subtriangular, the 

 ventral line strongly convex, the apex obtuse. Surface of the valves marked by a broad, 

 rounded, and encircling ridge, which is best developed towards the anterior and ventral 

 margins, the space thus enclosed being crossed obliquely near the middle by another 

 similar ridge, and marked also with numerous small circular impressed punctures ; the 

 ventral surface shows similar pittings arranged in curved longitudinal lines. Length, 

 l-50th of an inch ('5 mm.). 



A few valves found in a sounding fi-om 160 fathoms off the Coast of Patagonia 

 (Station 305). Approaching closely in general appearance to Cytheropteron nodosum, 

 Brady (a European species), but much more angular in outUne and more tumid ; different 

 also in some minor details of surface-sculpture. 



[PL XXXIII. fig. 7, a-d. a Eight valve seen from side, h from above, c from below, 

 d from front. All magnified 60 diameters.] 



8. Cytheropteron fenestratum, n. sp. (PL XXXIV. fig. 6, a-d). 



Shell, seen from the side, oblong, subovate, much higher in front than behind, 

 greatest height situated in the middle, and equal to more than half the length ; anterior 

 extremity broadly rounded and fringed with a series of twelve to fifteen short, broad, 

 and nearly equal teeth ; posterior extremity produced and narrowed, bordered with a 

 squamous lamina, which is divided into a number of short, subequal teeth ; dorsal margin 

 boldly arched, rather flattened in the middle, and sloping steeply towards each extremity, 



