 There is a further small panel in Lisbon of a female head , richly or <unk> dressed , which first appeared in 1907 with the Joseph panel when it was recorded in the inventory of Leo <unk> at <unk> . The figure may represent Saint Catherine of Alexandria , and from both the angle of her cloth and the fact that the river behind her would be parallel to that in the exterior of the London panel it can be assumed that she was kneeling . In the Stockholm drawing she is omitted , or only traces of her dress shown . The Joseph panel has a <unk> of a view through a window to an exterior scene ; if the other female is presumed to be kneeling , the trees above the waterway <unk> with those in the London panel . Some art historians , including Martin Davies and John Ward , have been slow to allow the Catherine panel as part of the altarpiece , though it is undoubtedly by van der Weyden or a near @-@ contemporary follower . Evidence against this link includes the fact that the moulding of the window to the left of the Gulbenkian female saint is plain , while that next to Saint Joseph is <unk> . Such an inconsistency in a single van der Weyden work is unusual . The panels are of equal thickness ( 1 @.@ 3 cm ) and of near @-@ identical size ; the Saint Catherine panel measures 18 @.@ 6 cm × 21 @.@ 7 cm ( 7 @.@ 3 in × 8 @.@ 5 in ) , the Saint Joseph 18 @.@ 2 cm × 21 cm ( 7 @.@ 2 in × 8 @.@ 3 in ) . 
