. Bulletin of the Natural Histort Museum. Geology series. FOSSIL PSEUDASTURID BIRDS Tentatively referred London Clay specimens Material. BMNH A 6224 (Fig. 2G), a proximal end of a right tarsometatarsus and portion of siiaft (lacking the crista intermediae hypotarsi). BMNH A 5193 (Fig. 3), a proximal end of a right tarsometarsus (referred to 'Primobucco' olsoni Feduccia & Martin [Aves, Piciformes] by Harrison, 1982). A complete description of this element was provided by Harrison (1982). Geological age and localities . Both the specimens BMNH A 6224 and A 5193 were collected from divisions
. Bulletin of the Natural Histort Museum. Geology series. FOSSIL PSEUDASTURID BIRDS Tentatively referred London Clay specimens Material. BMNH A 6224 (Fig. 2G), a proximal end of a right tarsometatarsus and portion of siiaft (lacking the crista intermediae hypotarsi). BMNH A 5193 (Fig. 3), a proximal end of a right tarsometarsus (referred to 'Primobucco' olsoni Feduccia & Martin [Aves, Piciformes] by Harrison, 1982). A complete description of this element was provided by Harrison (1982). Geological age and localities . Both the specimens BMNH A 6224 and A 5193 were collected from divisions D-E of the London Clay Formation at Warden Point, Isle of Sheppey, Kent, England (A 6224 collected and presented by Mr. D. Ward in 1982; A 5193 collected and presented by Mr. S. Silverstein in 1980). The age of these beds of the London Clay Formation is approximately My a (after Harland et ai, 1990; Berggren et al. 1995). BMNH A 6224 Tarsometatarsus (Fig. 2G). The proximal tarsometatarsus of BMNH A 6224 has a smoothly flattened medial shaft and a flat hypotarsus; the rims of the medial and lateral cotyles (cotylae mediale and laterale) extend distally to about the same level, the area intercotylaris is not raised significantly above the surface of the cotyles. On the proximal surface, both the cotyles are rounded in outline and have raised lateral rims. There are two preserved cristae intermediae hypotarsi. Two oblong proximal foramina are seen on the surface of the shaft; the outer one is somewhat larger but they are both at the same level on the proximal shaft. Measurements Bmnh a 6224: proximal right tarsometatarsus, total preserved length - , medio-lateral width of hypotarsus - Bmnh A 5193: proximal right tarsometatarsus, total preserved length - , width of distal end - , width at tibialis articus scar- (Harrison, 1982). COMPARISONS AND REMARKS Although the tarsometatarsi are clearly visible in dorsal view on the Messel pseudasturid specimen
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