202 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I44 



Comparison zvith other genera. — Lambert and Thiery (1921, p. 

 371) and Mortensen (1948, p. 247) considered Kephrenia a synonym 

 of Pliolampas. In Kephrenia, however, the petals are closed and have 

 narrow poriferous zones, whereas in Pliolampas they are open and 

 have very broad poriferous zones. It differs from Gitolampas in 

 having a transverse periproct and a higher than wide peristome. 



Remarks. — Fourtau, in his description of the genus, states that 

 its periproct is supramarginal, but in the holotype of the type species 

 it is marginal to inframarginal and visible adorally. 



Range and distribution. — Eocene of Egypt. 



DESCRIPTION OF TYPE SPECIES 



KEPHRENIA LORIOLI Fourtau 



Plate 38, figures 1-6; text figure 167 



Kephrenia lorioli Fourtau, 1909. Bull. Inst, figypt., ser. S, vol. 2, p. 139, pi. 9, 

 figs. 1-5. 



Material. — Holotype and two paratypes studied. 



Shape. — Small to medium size, low, elongate, posterior margin 

 pointed, anterior margin rounded, greatest width posterior to center, 

 adapical and adoral surface flattened. 



Apical system. — Slightly anterior, monobasal, four genital pores. 



Ambulacra. — Petals equal length, broad, closing distally, inter- 

 poriferous zone twice width of poriferous zone; pore pairs conjugate, 

 outer pore transversely elongate, inner round; poriferous zones 

 tapering distally. 



Periproct. — Slightly marginal to inframarginal, slightly visible 

 adorally, transverse, slight groove adoral to opening. 



Peristome. — Anterior, pentagonal, higher than wide, slightly de- 

 pressed around opening. 



Floscclle. — Bourrelets well developed ; phyllodes single pored (text 

 fig. 167), eight pores in each outer series, three in each inner; buccal 

 pores present. 



Tuberciilation. — Adorally, tubercles slightly larger than adapically ; 

 presence or absence of naked medial zone in interambulacrum 5 

 not clear on specimens studied. 



Occurrence. — Lower Eocene, east of Minia, Egypt, 



Location of type specimens. — Geological Museum, Cairo, Egypt. 



Remarks. — Gorodiski (1951, p. 325) described what he considered 

 to be a variety of this species from the Middle Eocene of Senegal. 



