And, where did the upper case in my subject line go? I actually copied it and pasted into the body of my OP. Curious? And I corrected it in the subject line to this follow-up and it went poof. Curiouser?

Albert, I just read this recently on a site referenced in the link. The last sentence is a little sad, I think. I love the old herbarium sheets and botanical illustrations. Microscopes and DNA tests aren't nearly as romantic. smile. josh

One last point that people should recognize is that the identification of plants is an ongoing process, and that plant taxonomy is neither absolute nor fixed, but merely reflects the current state of our knowledge. The ancients attempted to relate types of plants based on what were then the most visible and obvious characteristics. Without microscopes, the smaller features of plant physiology were unknown to them. As our ability to discern smaller and smaller structures has increased, naturally we can get a better idea of what plants are related to what other plants. But the advent of the electron microscope and even more the rise of genetic analysis will no doubt show us many new things and cause many plant relationships to be altered. It is indeed ironic that we are facing a future in which our knowledge and our ability to gain knowledge will have have become so great that we will no longer be able to definitively identify the species of a plant in the field or even under a laboratory microscope.

Here is a link that might be useful: Botanical Nomenclature

Albert - it has certainly changed some categories of plants leading to much confusion to those of us on the selling end! The ability to see plants as more than a 'daisy' head has led to Feverfew being part of several families in the last 10 yrs - Chamomile, Chrysanthemum and now Tanecetum (I think). Most growers still go by Hortus III but sometimes the guys in dark dusty university halls change the name and it takes time for that to filter thru.