660 



MR. F. CHAPMAN ON KAINOZOIC 



[Nov. 191 1, 



section, and the character of the pillars in the outer layer, suffi- 

 ciently determine the species. The present specimens are only of 

 moderate dimensions, since D'Archiac recorded this form as having a 

 diameter as great as 50 mm. The average length of the chambers 

 in the present examples is *125 mm. ; width of ditto = *025 mm. 



0. pratti occurs typically at Kressenberg (Middle Eocene) and 

 Biarritz (Upper Eocene). 



Lepidocyclina elephantina Munier-Chalmas. 



L. elejphantina Munier-Chalmas, 1891, ' Etude du Tithonique, du Cretace & du 

 Tertiaire du Vicentin. These de Doctorat' : Paris, pp. 71-77, 90 ; Prel. Note 

 (Bull. Soc. Geol. France, ser. 3, vol. xix, p. xxxii). See also P. Lemoine 

 & R. Douville, 1904, Mem. Soc. Geol. France, vol. xii, no. 32, fasc. ii, p. 13 

 & pi. ii, figs. 13, 19. 



A limestone (No. 41) from the Wadi Umzigga consists almost 

 wholly of the agglomerated tests of this species, which is the 

 largest known Lepidocyclina. It reaches a diameter of 8 to 10 cm., 

 according to MM. Lemoine & Douville. It is closely allied to 

 L. dilattita Michelotti, an Aquitanian species which, however, in 

 the microspheric stage, or form with the larger test, attains a 

 diameter of only 4 centimetres. 



One fragment in a thin section shows a raegasphere which 

 measures about V37 mm. in diameter; the thickness of the inter- 

 mediate area of the test is about 6f> mm. On the authority ot 

 Lemoine & R. Douville l (1904), L. elephantina is typical of Aqui- 

 tanian beds in Italy : while H. Douville 2 holds that the species 

 is Stampian (Upper Oligocene). 



Ostracoda. 



LOXOCONCHA CYEENAICA sp. UOV. 



Description. — Valves in side view, subquadrate; anterior border 



rounded below and obliquely 



Loxoconcha cyrenaica, 



Sp. 710V. x 40. 



[No. 28 from near Bint, east of 

 Derna, Middle Eocene.] 



below and 

 truncate above ; posterior ex- 

 tremity bluntly acuminate ; ven- 

 tral border sinuous, and convex 

 in the posterior third ; dorsal 

 border nearly straight. Edge 

 view, subtrigonal, thickest in the 

 posterior third, sloping evenly 

 towards the anterior edge. Sur- 

 face of the valves covered with 

 fine prickles ; the sulcus behind 

 the anterior margin is relieved by 

 a few large pits, with evidence of 

 less conspicuous pits along the 

 extreme anterior margin. 



Mem. Soc. Geol. France, vol. xii, fasc. ii, No. 32, p. 31. 

 Bull. Soc. Geol. France, ser. 4, vol. vii (1907) p. 468. 



