INDIAN AND PERSIAN GONIOPORA. 93 



There seems to be considerable uncertainty as to the age of the olive shales in which the 

 Jakhmari specimens occur. Duncan regarded them as Cretaceous, but see Medlicott and 

 Blanford's ' Manual of the Geology of India,' 2nd edition (R. D. Oldham) 1893, p. 287. No 

 argument in favour of the earlier beds can be based upon the fact that the growth-form of the 

 specimens is primitive, for other fossil Gonioporw with the same growth-form are known to be 

 Eocene. 



Geol. Dept. R. 13, presented by the Geol. Survey India. 



63. Goniopora Sind (7 )2. 



[South-west of Lynyan, Ranikot Group (Lower Eocene), coll. Geol. Survey, India.] 



Litlmrasa grandis, Duncan, Sind Fossil Corals, Mem. Geol. Surv. India (1880) p. 57, pi. xi. figs. 11, 

 12, 13. 



Description. — The corallum is of the primitive shape, only slightly convex above, 25 mm. 

 high and 9 cm. diameter, but below fiat round the edges and concave in the centre. [The 

 specimen was elliptical in outline and the epitheca had disappeared.] 



The calicles are very large, 10 mm., some even 12*5 mm. in diameter, polygonal and 

 shallow. The walls are stout, reticular, of irregular outline, sometimes protuberant. The 

 septa in three regular and distinct cycles in the typical formula, each septum stout, plain 

 (i.e. non echinulate), often wavy and not very perforate. Both primaries and secondaries 

 meet the small columellar tangle. The interseptal loculi are large and open. 



Imperfect tabular are formed. 



This Goniopora stands alone in the large size of its calicles, some 4 mm. larger than the 

 calicles of any other known form, and without any increase in the number of septa. 



Duncan added to the description that this " species " is closely allied to G. Sind 1 (his 

 " epithecata"), but differs only in size of calicles and "absence of epitheca." The latter 

 distinction must have been purely accidental. Other distinctions also can be seen in the 

 characters of the septa and walls. 



There is no specimen of this or the three following Gonioporw in the National Collection. 



64. Goniopora Sind (7)3. 



[Jhirk, Ranikot Group (Lower Eocene), coll. Geol. Survey, India.] 



Porites superposita, Duncan, Sind Fossil Corals, Mem. Geol. Sun. India (1880) p. 57, pi. xiv. figs. 5 

 and 6. 



Description. — Corallum small, elliptical, convex ; fresh growths do not quite cover those 

 which preceded them, so that the stock is an irregular pile of convex plates. 



The calicles are 2 mm. across, polygonal, often circular, walls frequently reticular. 

 Septa (24) closely crowded, not much thicker near the wall than near the centre, in three 

 distinct cycles, sometimes fusing but often free, and thus not always showing the typical 

 formula. The columellar tangle large, rises to the surface as granules. The perforations of 

 the septa are said to be small. 



