the PalcBOzoic Bivalved Entomostraca. 57 



ohsoleta and P. ovata, both of Scandinavian origin (see Ann. 

 Nat. Hist. ser. 3. vol. xvi. pi. 13. figs. 12 & 13). Rare. 



1. Cy there Wrightiana^ sp. nov. PL YII. figs. 5 a, 5 h. 



Carapace smooth, elongate-reniform or subcylindrical, like 

 a haricot bean ; ends nearly equal in curvature and compres- 

 sion ; but one (the anterior) is rather more elliptical and rather 

 more compressed than the other ; dorsal line elliptic ; ventral 

 line slightly sinuate, being somewhat incurved at the middle. 

 Dorsal profile elongate-ovate. Rare. 



Modifications of this shape are not uncommon among the 

 carapaces of Cythere, both recent and fossil ; but we cannot 

 definitely match this form with any known species. The same 

 may be said of those that follow. 



We have named this old Cythere after Mr. Joseph Wright, 

 F.G.S., to whose care we owe the many well-preserved speci- 

 mens of Entomostraca that we have seen from Kildare. 



2. Cythere Jukesiana, sp. nov. PI. VII. figs. Qa,Qh. 



Carapace subcylindrical, but very much narrower and rather 

 more compressed at one end (anterior) than at the other, — in 

 fact strongly tapering from the posterior third forwards. The 

 back is arched behind the middle, and the ventral margin is 

 incurved a little in front of the middle. Ends elliptical in 

 curve ; the posterior is broader than the anterior extremity. 

 Dorsal profile subovate, acute at the ends and compressed at 

 the sides. Rare. 



Named after the Director of the Geological Survey of Ireland. 



3. Cythere Bailyana, sp. nov. PI. VII. figs. 1 a,Tb. 



Carapace smooth, somewhat bean-shaped ; straight on the 

 back, rounded nearly equally and attenuated at the ends ; in- 

 curved and compressed at the middle of the ventral region. 

 Dorsal profile acute-oval, laterally compressed. Rare. 



Named after the Palasontologist of the Geological Survey of 

 Ireland. 



4. Cythere Harhnessiana, sp. nov. PL VII. figs. 8 a, 8 ^. 



Carapace smooth, nearly ovate ; the back is more strongly 

 arched than the ventral edge ; and these opposite margins have 

 their greatest convexity in an oblique direction one to the 

 other — that of the ventral margin being in advance of the 

 middle, and that of the back rather behind it. Dorsal profile 

 nearly oval, but subacute at the ends. Rare. 



We dedicate this Lower- Silurian species to Prof. Harkness, 

 F.R.S., of Queen's College, Cork, who has laboured on the 

 Palasozoic rocks of Ireland and the north of England. 



