444 Norman Taylor— The Cudgegong Diamond Field, 



Septa excessively numerous, the longer ones alternating with the 

 shorter ; septa or pali, furnished with numerous synapticulae. 

 Formation and Locality : — The same as the last-named species. 



EXPLANATION OF PLATE XI. 



Fig. 1. Cyrena sinuosa, Deshayes, subfossil, Sumatra. 

 ,, 2. Pectunculus (cast of), Tertiary Clay-marl, Island of Nias, W. Coast of 



Sumatra. 

 ,, 3. Venus ? non-scripta, Sby., Island of Nias, W. Coast of Sumatra. 

 „ 4. Pema, sp. (fragment of hinge) „ ,, 



,, 5. Pecten asper, Sby. (flat valve) „ ,, 



,, 6. , Sby. (convex valve) „ ,, 



,, 7. Asper gillum (Javanum ?) „ ,, 



„ 8. Acanthocyathus, sp., Tertiary, Grey Sandy Clay, Island of Nias, 



"West Coast of Sumatra. 

 ,, 9. Montlivaltia, sp., (a) side-view; (b) view of top. 

 „ 10. , (a) side-view ; (b) view of the interior of the calyx. 



Tertiary Clay Marl, Island of Nias, West Coast of Sumatra. 

 „ 11. Fungia, sp. (view of under-side), loc. ibid. 



{To be continued in our next Number.') 



IV. — On the Cudgegong Diamond Field, New South Wales. 1 



By Norman Taylor, Esq., of the late Geological Survey of Victoria. 



Communicated by E,. Etheridge, jun., F.G.S. ; of the British Museum. 



The next appearance of the older lead is at the '■'Kocky-ridge," 

 where the river, after running northerly for three-quarters of a mile, 

 along the strike of the metamorphic beds, turns abruptly to the 

 west. This ridge is a basalt-capped hill on the north side of the 

 river, running in a north-west direction ; it is about a mile long, 

 with a bold rocky escarpment on its west side, facing the Sandy or 

 Cudgebeyong Creek. Some tunnels have been driven in, and shafts 

 sunk on this hill, and tolerably rich deposits of gold were found, but 

 never followed out. Only in the southern half of the hill have 

 diamonds been found (all more or less spotted) . The drift is remark- 

 able for the number and size of the agates it contains. The northern 

 half of " the ridge " is underlaid by another outlier of the before- 

 mentioned doubtful purple conglomerate, into which some tunnels 

 have been driven in the western escarpment. The basalt is merely 

 a fringe here, resting against the flank of the conglomerate hill to 

 the east. A few inches of drift rest upon this conglomerate, in which 

 a small quantity of nuggetty gold was obtained ; and from one 

 to two inches thickness of lignite, or carbonaceous clay, is seen 

 between it and the bottom of the basalt. The basalt is intersected 

 by numerous veins of a mineral allied to kaolin. The purple con- 

 glomerate is similar in character to that near " the flat," and contains, 

 on some of the joint faces, small spherical crystalline aggregations of 

 chalybite (carbonate of iron). At the extreme north end of "the 

 ridge " are great quantities of ironstone and conglomerate, but, 

 from their mode of occurrence, I should imagine them to be part of 

 the Carboniferous series, which is largely developed further north. 

 The first diamonds which found their way to Melbourne were obtained 

 1 Concluded from page 412. 



