49 



ROPERIA. 



GENUS 151. ROPERIA GRUN., in H.V.H. Atl., 1885. 



Fig. 226. Roperia tessalata. 



Valve circular or subcircular, with 

 plane surface, structure cellular, cells 

 punctate, puncta decussate, furnished 

 near the margin with a round hyaline 

 spot or pseudo-ocellus. 



A single species. 



R. tessalata (Roper) Grun. 



(in H.V.H. Atl., pi. 118, f. 6* Eupodiscus 

 tessalatus Roper; QJ.M.S.., 1858, vi., p. 19, 

 pi. 3, f. 1 a-b\ fig. 226 in text. 



Valve from 6 to 7 c.d.m., having about 6 

 cells in 1 c.d.m. near the middle of the valve, 

 smaller and more approximate near the margin. 



Hyaline spot, about "25 c.d.m. in diameter. 



Marine. England: Caldy, Pembrokeshire (Roper), Hull (Norman, Gregory, Greville) 

 Finistere (Greville). West Coasts of Africa (" Gazelle " Expedition, Weissrlog). 



Cape 



GENUS 152. ISODISCUS, RATTRAY, 1888. 







".v.v.V.-> - -v.; v ;4-^r.:v :; 



>.! ;.*.:* 



Fig. 227. Isodiscus mirificus. 



Valves circular, with coarse puncta, 

 furnished at the margin with 2-3 large 

 processes, surrounded by fine radiating 

 puncta, and between them several 

 pseudo-ocelli. 



This genus only includes two species, 

 both fossil, from Oamaru. I give in the 

 text I. mirificus Raft., after Rattray (fig. 



227). 



