REPORT ON THE OSTRACODA. 13J 



small, with short, recurved claws ; eyes clistmct. Copulative organs of the male very com- 

 plex, provided with several irregular processes and a very long spu-ally convoluted tube. 



The members of this genus appear to be distributed abundantly over the whole globe, 

 and are perhaps equally common in the Arctic Seas, as in those of the tropical and 

 temperate regions. With very few exceptions, they are the smallest of all the Ostracoda, 

 the usual range of length being between l-50th and l-70th of an inch. 



1. Cytherura curvistriata, n. sp. (PL XXXII. fig. 10, a-d). 



Carapace oblong, tumid ; seen from the side, subrhomboidal, about equal in height 

 throughout, scarcely twice as long as high ; anterior extremity obliquely rounded, 

 posterior angular, tapering abruptly and broadly truncated in the middle ; dorsal and 

 ventral margins parallel and nearly straight ; seen from above, the outline is l^roadly 

 ovate, greatest width behind the middje and equal to more than half the length, broadly 

 mucronate in ' front, hinder extremity broadly rounded and irregularly emarginate ; end 

 view subeUiptical, height less than the width. Surface of the shell marked with not very 

 prominent, flexuous, longitudinal ribs, the intervals between which are pitted with 

 angular cavities. Length, l-62d of an inch ("40 mm.). 



Dredged at Port Jackson, Australia, in a depth of 2 to 10 fathoms. 



[PL XXXII. fig. 10, a-d. a Carapace seen from left side, b from above, c from 

 below, d from front. Magnified 60 diameters.] 



2. Cytherura ohliqua, n. sp. (PL XXXII. fig. 1, a-d). 



Carapace oblong, tumid ; seen from the side, flexuous, subrhomboidal, higher in front 

 than behind, height equal to about two-thirds of the length ; anterior extremity broad 

 and obliquely rounded off, posterior rounded but much narrower, not beaked; dorsal 

 margin moderately arched, ventral somewhat convex and sinuated towards the front ; 

 seen from above, the outline is hexagonal, scarcely twice as long as broad ; the sides 

 parallel in the middle but converging rather abruptly towards the ends ; end view heart- 

 shaped, broad at the base and tapering to an obtusely rounded summit, height greater 

 than the -width. Shell marked with rather large angular excavations, and on the ventral 

 surface with sinuous longitudinal grooves. Length, l-43d of an inch ('58 mm.). 



The only dredging in which I have seen Cytherura ohliqua is from 20 to 50 fathoms 

 at Balfour Bay, Kerguelen Island (Station 149). The species is rather anomalous in 

 character, having a good deal of the general contour of Loxoconcha, and being destitute 

 of the beak, which is the chief external mark of Cytherura. The same remarks apply 

 partially to the two next described species Cytherura mdis and Cytherura cribrosa ; the 

 generic position here assigned to them must be looked upon as merely conjectural. 



[PL XXXII. fig. 1, a-d. a Carapace seen from left side, b from above, c from below, 

 d from front. Magnified 50 diameters.] 



