> Ryan, is this an oversight or is it intentional?
When preparing the monster sections of the SRD, I tried to remove all specific physical descriptions of the creatures. I did that because it would be very hard for a publisher to understand the difference between creating a derivative work based on WotC's illustration, and creating a derivative work based on a physical description. The former is a copyright infringement, the latter would be standard use of the OGL.
The SRD is drafted with an eye towards making it as easy as possible to tell a publisher "if you use what's in the SRD and ignore D&D, you >will< comply with the OGL, and the d20 System Trademark License, and won't infringe WotC's copyrights or trademarks".
Thus, if you want to create illustrations for creatures in the SRD, you need to create them from whole cloth, not by starting with the description in the Monster Manual. For most creatures, that's neither hard to do, nor very time consuming. For a handful, it's both. For most of the creatures, the illustrations you're likely to create will be recognizable to the average gamer, because those monsters are drawn from myth and legend and have commonly accepted forms and shapes. For the handful that don't, you are a bit out of luck. (Although, as I said before, they could be black-boxed. If you started with someone who had never seen an illustration of a Mind-Flayer, and gave them the SRD
description, and they gave you back an illustration of an octopus-headed humanoid, you'd be in the clear, since your work was not derivative of WotC's copyright).