Vol. 70.] MIOCEXE OF THE VICTORIA XYA>~ZA, ETC. 133 



and in the gully of South Xira Xos. 28 & 29 are altogether 

 absent. 



This group of gravels rests upon a remarkably persistent con- 

 glomerate (No. 30) of calcareous nodules (but not extending far 

 to the east of Kachuku), passing in places into a nodular sand- 

 stone of such hardness that, where it has been undercut by the 

 action of temporary waterfalls in the gullies, it only breaks off in 

 large slabs measuring 12 by 4 feet or thereabouts (PL XXII, 

 fig. 1). In some cases I found a nodule, with its many concentric 

 coats, containing a fossil, such as a Trionyx scute, for a nucleus ; 

 but often no definite nucleus could be traced. The nodules have 

 not been sorted according to size, but lie haphazard in a white 

 calcareous cement, from small pebbles up to boulders 2 feet in 

 diameter. They are always, however, ellipsoidal like river-pebbles 

 and, when they are fractured, the fracture-planes prove to be' 

 frequently coated with dendritic manganese. 



Below this conglomerate occurs a very variable group (Xo. 31) 

 of grey or brown clay with Ampullaria ovata Olivier and 

 Cleopatra hulimoides Olivier, brown seams of rnarlstone, and 

 calcareous conglomerate at the western end (at Xira) of the out- 

 crop ; but towards the east, at Kachuku, this group (only exposed 

 in a narrow gully) consists of 6 feet of grey clay overlying 14 feet 

 of hard buff-coloured sandstones, current-bedded and having streaks 

 of pebbles, very similar to the Triassic pebble-beds at Xottingham. 

 They enclose two zones of gravel composed of overlapping lenti- 

 cular beds (the pebbles consisting simply of quartz and ironstone), 

 and it was only in these hard gravels that bones occurred, often 

 much shattered and fragmentary, and at wide and uncertain 

 intervals. 



The upper gravel zone immediately underlies a discontinuous 

 layer of yellow rnarlstone (PI. XXII, fig. 2), and is particularly 

 characterized by remains of Dinotlierium and Anthracotheres 

 (Bracliyodus, Herycopotamus, Jlerycops africanus, etc.), Rhino- 

 ceros, a Carnivore (Pseud eel in* us africaaus), part of the carapace 

 of a giant Tortoise (Testudo), Trionyx, Crocodile, and a land-shell 

 (Cerastus moellendorffi). 



In the lower gravel zone only much shattered Chelonian 

 remains were present. Grey travertine, 2 feet thick, is visible at 

 the base of this zone. 



Xos. 32 to 36 form a variable group of brown clays, alternating 

 with orange-brown rnarlstone (32 <fc 34) containing Ampullaria 

 and Cleopatra, and often exhibiting small cavities lined with 

 calcite-crystals. At West Kachuku this group passes into brown 

 clay with layers of travertine, overlying a buff-coloured sandstone 

 enclosing streaks of gravel and lenticles of travertine. This in 

 turn overlies an orange-brown rnarlstone containing so much 

 angular quartz that it becomes a quartz-ironstone breccia, facing 

 the Kuja Plain in a low cliff at West Kachuku. 



Finally, the lowest bed (Xo. 37) is a mottled dark-crimson 

 and yellow clay (6 to 12 feet) overlying (at Xira) a dark- 



