Skip Williams very kindly sent me a copy of the paper I was asking about earlier today (I say this partly to save anyone else the trouble); for those who also did know it, this is the reference:

Cotte J. and Cotte C. 1917. Analyses de résidus organiques de l'époque néolithique (Caverne de l'Adaouste). Bulletins et Mémoires de la Société d'anthropologie de Paris, VI° Série. Tome 8 fascicule 1-2, 66-115.

... and it's pretty clear that the material described cannot all be neolithic. The paper refers to (if my primitive French is accurate)

- rye (Secale) and oat (Avena) grains

- fibres, some of which were flax.some Cannabis, and some  of which were blue - which led them to suppose woad had been used to colour them

- some red fibres they claim to have been dyed with the insect dye kermes

- and hairs they claim to be from mammoth (Mammuthus)

I'm not sure in the end that there were any remains of woad seeds or any other parts of the plant.

It's a fascinating example of very early forensic archaeobotany - bringing in some chemistry as well as microscopy of plant residues. But it does not sound as though the dating is good. My next - inevitable question - is to ask whether anyone knows of a critique of this report? If it is as dubious as it seems, it's a great shame that the record of woad is propagated so repeatedly on the web.

With all good wishes

Allan
--
Dr Allan Hall, Senior Research Fellow, Department of Archaeology, University of York, King's Manor, York YO1 7EP, UK
+44 1904 434950 (fax 433902)
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http://www.york.ac.uk/archaeology/staff/academic-staff/allan-hall/
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