[links checked; tags added. 2/03/2015]
In their paper, ‘A Preliminary Analysis of the Botany, Zoology, and Mineralogy of the Voynich Manuscript’, Tucker and Talbert offer identifications for a number of plants, among which is that of Opuntia ficus indica for a detail on folio 100r. You can
download the pdf of see their paper here.
I agree that the detail shows a leaf and root of what appears to be a succulent, but the supposed ‘spines’ are shown rather too rounded for a sharp spine in my opinion, and I rather think the plant might be a Kalanchoe – perhaps K. pinnata – an identification which would be more in keeping with other details on the same folio and with the character of the manuscript’s imagery overall.
K. pinnata occurs widely but is a native of Madagascar. Known as the ‘air plant’, ‘miracle plant’ or ‘live forever’ plant. I have not researched its traditional non-medical uses.
As so often, taxonomic description in this case has been subject to constant alteration and refinement, but at present:
The genus Kalanchoe includes about 145 species native to the Old World, especially southern Africa, Arabia and South East Asia. Some species of Kalanchoe are characterized by the capability to produce plantlets in notches at the margin of the leaf blade. Two varieties of K. pinnata are recognized in a revision of the Kalanchoe of Madagascar (Boiteau and Allorge-Boiteau, 1995), namely K. pinnata var. pinnata and var. genuina.
quoted from cabi factsheet No.29328
An excellent summary of information and a number of photographs about it on this page. (in Spanish). Link broken (2/03/2015)
I’d argue that the longer ‘spines’ in that detail from folio 100r indicate the plant’s flower buds, and that the otherwise evenly rippled margin represents the leaf’s constant appearance.
On folio 100r, the next lower register also includes two more leaves of similar appearance and approximately similar form. One of them has the leaf drawn almost perfectly circular, so here too one might suggest another Kalanchoe, and another often described as native to Madagascar – K. Fedtschenkoi.
But I am no botanist, though, let alone a specialist in eastern plants, the point here being, really, is that even granted that these are intended as images of succulents, alone it does not constitute proof of content obtained in the Americas. One very difficult objection which those espousing the ‘Nahuatl’ argument will have to overcome is the apparent absence of any sign that the parchment and inks were used much later than c.1438.
Those offering the ‘Nahuatl’ scenario will have to offer evidence – and I do mean evidence, not just rationalisation – that the parchment and/or inks and pigments were used six decades or more after the parchment’s date. Ideally, too, they should be able to comment on (and explain) the manuscript’s dimensions – which better agree with earlier works – and comment on the marks left by previous bindings. Admittedly the last are so poorly described and understood at present I doubt anyone would pay attention to comments made by anyone other than an eminent comparative codicologist who’d seen the manuscript at first hand.
So much said, I have to say that I’ve noticedsome interesting similarities between some maps made for a Spanish Latin audience and the Voynich manuscript’s “bathy-” section. Since it hasn’t convinced me to become a follower of the ‘Nahuatl’ camp yet, I’ll leave those revelations to someone who is.