If it's a medicinal why the lack of accuracy?

[BessAgritianin]

The botanical accuracy was not priority in many medieval herbals which often represented the plants stylized or schematically.
 For example consider the garlic representation from "Gart der Gesundheit" (1485) and the build in its translation in "Ivan the Terrible Travnik". Neither the first nor the second image would be recognizable from the contermporary man if not for the description. 
However the text lists that the garlic remedies are so numerous-  from head lice to intenstinal worms to heart ailments,  that the today medical practitionaries would never dream of... 
It starts also with the history of the great Masters in medicine- what they have written about the herb.