262 Prof. T. E. Jones and Mr. J. W. Kirkby on the 



imperfectly. They are very curious Ostracods, apparently 

 more nearly related to Kirlhya than to any otlier group. 



31. Cytherella (?) reticulosa, J. & K. 

 (PI. VIII. tigs. 22 a, 22 h.) 



Cytherella? rettculosa, J. & K., MS. 1885, Geol. Mag. dec. 3, vol. ii. 

 p. 640. 



Oblong ; dorsal and ventral borders straight and parallel ; 

 ends rounded, one a tritle more prominent than the other ; 

 valves moderately convex, and apparently not very unequal 

 in size ; surface regularly reticulated, mesh rather large ; a 

 round muscle-spot is seen in the centre of the valve, in casts. 

 Length i's^ to -jV inch. 



This neat little form has the aspect of Cytherella, and we 

 place it in that genus on that account, though with some 

 doubt, as there is not the usual difference in the size of valves 

 of Cytherella, and we have not seen any interiors. 



It has occurred in the Carboniferous-Limestone series at 

 Dun Quarry (Lowick), Northumberland; and in the Scar 

 Limestone, north of Storr Moss, Westmoreland. 



32. Cytherella valida, J. & K., var. agitata. 

 (PI. IX. figs. 1 «, 1 Ij^i 



Subpentagonal in outline, compressed, urabilicated ; dorsal 

 border subangulate ; ventral border straight; anterior extremity 

 rounded and larger than the posterior, which latter is obliquely 

 truncate; lateral contour much compressed, pointed in front, 

 truncate behind ; surface smooth. Length -^-^ inch. 



This form resembles C. valida in general outline, but differs 

 from it in its compressed and posteriorly truncated lateral 

 contour ; also in its central pit or umbilicus. For the present 

 we retain it under this species as a variety. 



A similar, though probably distinct, form occurs in the 

 Lower Carboniferous at Tweeden Burn and Pittenweem. 



Locality. In Yoredale beds at Gleaston Castle (near Bar- 

 row-in-Furness), Lancashire. 



33. Cytherella (?) elongata, sp. nov. 

 (PI. IX. figs. 2, 3.) 



Small, elongate, highest behind ; dorsal border straight and 

 long ; ventral border straight or flatly convex ; extremities 

 rounded (with dorsal angles) , the posterior being higher than 

 the anterior; free margins rimmed, the right overlapping the 

 left moderately ; shell thin ; surface smooth. Length ^ inch. 



