12 F. Chapman — Egyptian Foraniinifera. 



of * Conulites ' Coohi,^ both in the collection at the British Museum 

 (Natural History) - and in the Carter Collection at the Geological 

 Society, in order to make a comparison of the Indian with the 

 Egyptian species. In the collection at the Geological Society's 

 Museum the best specimens of Patellina Cooki are mounted on slide 

 No. 40 of the Carter Collection, and are numbered 2 (from Kelat), 

 3 (from Sind), and 4 (from Arabia). The sections of F. Coolci 

 show the cortical layer to consist of rectangular chambers, but 

 these, unlike the Egyptian specimens, are without the secondary 

 imperfect septa or dissepiments seen in the latter. 



Some West Indian specimens of Miocene age kindly lent me by 

 Mr. Jennings show this secondar^^ septation of the cortical layer, 

 but the chambers in these are more crowded and narrower than in 

 P. Egyptiensis, and the species is probably new. 



It is interesting to note that Patellina Cooki is associated with 

 the following foraminifera in the Indian limestone as given by 

 Carter in the paper above mentioned, namely : Alveolina elliptica, 

 Nummulites ohesa, N. perforata, N. Carteri, Assilina exponens, 

 A. spira, and Orhitoides dispansa. The limestone in which thesf^ 

 foi'aminifera occur appear to belong to the Kirthar Group (Eocene);^ 

 In these Eocene beds the shell-structure exhibits the simplest pla^i. 

 In the Egyptian beds, probably Lower Miocene, we have the inter- 

 mediate stage in the development of the cortical layer. Finally, iu 

 the West Indian Miocene, presumably newer in age, the transition 

 of the outer chambers is carried out still further. 



Thus there appears to be a progression of this form in a westerly 

 direction. 



? Lower Miocene : from a plateau between Cairo and Suez. Very 

 abundant, forming about 50 per cent, of the bulk of the rock. 



DISCOEBINA, Parker & Jones [1862]. 

 DisooRBiNA, sp., near D. globularis (d'Orbigny). 



Bosalina glohiilaris, d'Orb., 1826 : Ann. Sci. Nat., vol. vii, p. 271, 



pi. xiii, figs. 1-4; Modele, No. 69. 

 Discorhina globularis (d'Orb.), Parker, Jones, & Brady, 1865 : Ann. 



Mag. Nat. Hist., ser. in, vol. xvi, p. 30, pi. ii, fig. 69. 



Our specimen occurs in a section of the rock, but there is little 

 doubt, from the thick peripheral wall and globular segments, that 

 it is referable to the above species. It is a well-known fossil in 

 Middle Eocene, Miocene, and Pliocene beds. 



? Lower Miocene : from a plateau between Cairo and Suez. One 

 ■specimen. 



^ See Carter, 1861, Jouru. Bombay Br. Roy. As. See, vol. vi, p. 83. Also 

 Ann. Mag. Nat. Hist., ser. iii, vol. viii, p. 457. pi. xv, fig. 7. 



* To Mr. R. B. Newton and Mr. "W. R. Jones I am indebted for their kind 

 attention when examining these specimens at the British Museum and the Geological 

 Society. 



3 See Manual of Geology of India, 1893, Medlicott & Blanford, 2nd ed., revised 

 by R. D. Oldham, pp. 305-7. 



