[Talk] Voynich Talk Episode 1, part 1: A plant is not B plant

[Bernd]

I wonder what you think about veined leaves.

I think it's a stylistic preference and from what I have seen, venation is absent or wildly inaccurate in many herbals. If faithfully reproduced, venation can be valuable to identify plants, see
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I see no reason why the leaves drawn with veins in the VM should have them and others not.
The cases where the petiole ends in the middle of the leaf could represent the abaxial (under) side of the leaf. This side would usually have more prominent venation. Let's look at the plants with veined leaves and use + for the presumed adaxial (upper) and - for the presumed abaxial (under) side where the petiole reaches into leaves:

 f2v +
 f5v -
 f6r +
 f6v -
 f7r +
 f8r +
 f9v +
 f13r -
 f16v -
 f19r +
 f20r +
 f23v -
 f25r +
 f25v +
 f27r +
 f28v + (?)
 f30r +
 f36r -
 f41v + (?)
 f42r +
 f87v +
_______
15+ / 6-
So the veins = leaf underside hypothesis can pretty much be rejected.

In contrast we have petioles intruding leaves without veins:
f9r, f11r(?), f13v, f16r, f36v, f37v, f93v, You are not allowed to view links. Register or Login to view.
In You are not allowed to view links. Register or Login to view. the petiole appears to connect in the leaf center but on the invisible underside so I am not sure this counts. It does not intrude the drawn leaf. Anyway, this seems to correlate to leaf shape and they do appear to represent undersides most of the time. All leaves with intruding petiole have an overall circular shape and are either orbicular or digitate. We do not find any elongated leaves with this feature.
   
You are not allowed to view links. Register or Login to view. is the only case where the petiole reaches into a fruit/flower. Rather than the terrible paintjob suggests this could be an involucre seen from the abaxial side (from 'below') with the dots representing phyllaries (the spines) in frontal view. Something like a burr.
You are not allowed to view links. Register or Login to view. shows venation in the leaves but none in the stipulae. If you look at the Viola drawing from 1853 I posted above, it also mostly lacks venation in the stipulae, probably because of their small size. But they should at least have a mid-vein. So this ultimately is a stylistic choice.
You are not allowed to view links. Register or Login to view. appears to have some venation on the lowermost leaves which are connected by 2 petioles or stems
You are not allowed to view links. Register or Login to view. only has smaller 'bracts' with veins while the large main laves do not.
You are not allowed to view links. Register or Login to view. (B page) is weird, only few leaves have rudimentary venation and the petioles appear to be partly intruding into the leaves. It has a strong resemblance to f36r.

By the way, you still have  a mistake in your blog post in the section 'Typical A-calyx shape'
'It has a bulbous bottom and three tepals – the spiky leaves that surround the petals.'
You mean sepals not tepals. A tepal is a sepal that looks like a petal. All clear?