. Bulletin of the British Museum (Natural History), Geology. 58 P. M. P. ZABORSKI bulk of the described European Lower Turonian ammonites. A similar subdivision seems to be possible in the Lokpanta area of Nigeria (Fig. 45, p. 56). Here, beds dominated by Watinoceras spp. can probably be correlated with the zone of W. coloradoense. Lying above are beds clearly corresponding with the zone of M. nodosoides. They contain the nominal species, Fagesia and Kamerunoceras puebloense, all characteristic of this zone in the United States western interior (see Cobban & Scott 1972). Below the Turonian
. Bulletin of the British Museum (Natural History), Geology. 58 P. M. P. ZABORSKI bulk of the described European Lower Turonian ammonites. A similar subdivision seems to be possible in the Lokpanta area of Nigeria (Fig. 45, p. 56). Here, beds dominated by Watinoceras spp. can probably be correlated with the zone of W. coloradoense. Lying above are beds clearly corresponding with the zone of M. nodosoides. They contain the nominal species, Fagesia and Kamerunoceras puebloense, all characteristic of this zone in the United States western interior (see Cobban & Scott 1972). Below the Turonian beds at Lokpanta, shales have yielded a possible Metengonoceras which would indicate the presence of Upper Cenomanian sediments. If confirmed, this occurrence would form an interesting geographical link between beds of this age in north-east Nigeria, the middle Benue Valley and the Calabar region in the extreme south-east of Nigeria (see above, Zaborski 1985). The fauna from Ezillo described here is more difficult to date precisely. It contains both Thomasites and Wrightoceras, though the latter occurs a little above the former in north-east Nigeria (Barber 1957, Wozny & Kogbe 1983). Since the entire Ezillo fauna was collected loose from a section several metres thick, however, it is possible that these genera are strati- graphically separated here also. Clearly the affinities of the Ezillo population are with the vascoceratid forms occurring as much as 600 km north in Nigeria, having virtually nothing in common with those at Lokpanta, barely 60 km distant (see Fig. 46). In north-east Nigeria Thomasites gongilensis occurs with Paravascoceras, another Ezillo faunal element, in beds which, according to Hancock & Kennedy (1981), lie very close to, and possibly just below, the Cenomanian-Turonian boundary. Wrightoceras wallsi, on the other hand, is confined to the upper part of the fossiliferous sequences at Pindiga and Ashaka and is of early Turonian age. The ammonite-bea
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