A return to f25v - the dragon is the key, obviously, but is it basil?

[Searcher]

I would favor the poison-related explanations if more plants had been marked this way. In the VM large plants,  however, we get a single plant with a dragon and another with two snakes entwined in the roots. 

I admit there's some comfirmation bias on my part because the sap thing confirms Dracaena. It would also explain the dragon's sucking rather than biting appearance.  It would indeed be interesting to find out more about the reason why a dragon was apparently associated with plant sap.

Maybe, it was an influence of some ancient legends about dragons, which were mentioned in such work as the Natural History of Pliny, where he refered to Xanthus of Lydia and the king Juba II of Numidia and Mauritania. The matter is about an unknown herb named Balis (Balin, Balus, Balim), which returns to life dragon babies and, in the same time, a man killed by a dragon can be saved with the same plant. This fragment was quoted You are not allowed to view links. Register or Login to view. and You are not allowed to view links. Register or Login to view., for example.
There is the constant confusion with this herb(s) and its name. You are not allowed to view links. Register or Login to view.mentions two herbs: Balis and Batis, which are from the same story above. Now, it is hard to know, where is the correct information as originals are lost, but it is a big field for suppositions not only for us, but, likely, for ancient scholars, too.