I have a couple of notably small equids from a Roman site on the south coast of England. A small number of donkeys have been found in contemporary sites elsewhere in Britain, so I can't exclude donkey. However, only one longbone is fully fused and complete. Comparisons with a donkey and a pony at the English Heritage reference collection was less helpful, as my bones were right inbetween in size...
I also have one mandible, where the folds on some teeth are more like horse and some are more like donkey (using the pictures from Cluny Johnstone's Ph.D. as a guide - http://www.york.ac.uk/media/archaeology/documents/researchdegrees/phdthesis/CJohnstonePhDvol2.pdf (p.164-166)).
If anyone here could help me I would be very grateful. I have put photos of the bones up on a flickr set, with measurements where possible.
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