92 MADREPORARIA. 



column or lobe. It was proljalily the columnar growth which suggested the grouping of this 

 coral with the Red Sea form figured by Savigny in liis Descript. de I'Egypte, pi. v. fig. 2. It 

 appeared to me to be quite a different coral, and also different from the other form which 

 Dr. Klunzinger called G. Savignyi, and which, like tlie type, was from the Red Sea, see G. Red 

 Sea 3. 



The rounded tops and flat sides, with lamellate texture of the tops of the columns, leads 

 one to beUeve that this must be another instance of the expanding-sheaf formation referred to 

 in the Introduction, p. 26. It is worth noting that it is a very common growth-form of the 

 Eed Sea Gonioporm, see Table III. D, p. 171. 



Group v.— INDIA AND PERSIA. 



Containing descriptions or records of Fossil Go7iioporce from Sind (1-7) ; ? " Indus River " (1) ; 



Persia (1-4). 



G2. Goniopora Sind (7)1. 



[Jakhmari, Laki Eange, south-west of Amri (Cretaceous or Lower Eocene, in beds with 

 CarclUa Beaumonti), coll. Geol. Survey, India ; Calcutta and British Museums.] 



Litharcea epithecata, Duncan, Sind Fossil Corals, Mem. Geol. Surv. Irulia (1880) p. 23, pi. ii. figs. 1-9. 



Description. — Corallum thin, fiat, disc-shaped, slightly convex with sharp edges, free upon 

 a well-developed concentrically wrinkled epitheca ; under surface may be slightly concave. 



Calicles rather irregular, usually hexagonal, large up to 6 mm., smaller round the rim. 

 Walls thin, with sharp ridges, irregularly reticulate in sections and tending to rise into points at 

 the angles. Septa long, thin, wavy and conspicuous, in the typical formula, much perforated, 

 with enlargements and lateral echinulations, incised, and bluntly coronulate or moniliform on 

 the free edges, thicker near the wall. The columellar tangle is very slight and inconspicuous 

 at the surface. 



This primitive method of growth is now known to have persisted in other Gonioporm, see 

 Table III. As explained in the Introduction, all the other growth-forms of the genus can be 

 deduced from it.* 



The variety described by Duncan as r'ar. he7nispha:rica, (I.e. fig. 10) from "Barki nala," is 

 either an older growth-phase or the same coral with the disc more concave below and convex 

 above, for it is to be noted that the calicles are of the same type, and shallow. True hemi- 

 spherical forms would only occur if the calicles composing the colony were tall with deep fbssaj. 



It was Duncan's excellent figures of this coral which first led me to the discovery of the 

 septal formula characteristic of the genus. 



There is one rather poor specimen in the British Museum, showing no details of the 

 structure so beautifully illustrated by Duncan. 



* Duucan thought that the basal epitheca was a point of special importance, and Gregory 

 (Geol. Mag. (1898) p. 250) named certain free Egyptian forms "epithecata" without hesitation. See 

 p. 106. 



