Does anyone have any opinions regarding the condition depicted in the attached image?

Dale
How much light is it getting?

Either it's an old leaf ready to fall off which is normal, or you have a mineral deficiency or possibly a ph problem which would tie up certain minerals

Mario,

     That's the thing. It sits under four foot tubes, one cool, one warm and with other figs that don't have this condition. The only other fig afflicted is a clone of the same variety.

Barry,

     Until recently they were getting no fertilizer. Now they are getting Schulz Orchid Food half strength, because that's what I had handy, and I must say that all of the starts perked u pa bit. (It has some trace minerals in it.)

Dale I would also check the under side of the leaf with a magnifying glass and look for critters. It's possible that spidermites or some other noxious nasty is sucking the juice out. If it is only particular to the 2 trees of one variety it could very well be bugs or minerals that this variant is sensitive to.     

Had a rash of the critters a few weeks ago, but they gone now. The other figs infected with spider mites did not dispaly this symptom. It's odd that it seems to travel in these two figs only through the veins and that's why I am guessing it is something systemic.