It looks like your transmission cooler line (runs from the transmission cooler to the transmission). Look for a problem with the line underneath that black rubber piece. Look for cracks and/or a place where the line has been rubbing against something. You can either remove the line and have it brazed or just replace it. I have found that most of the lines like this are pretty reasonable in price. Are you sure that is the transmission fluid pan? Looks almost like the engine oil pan.

What is that in blue type say?

Jim
'85 300D
'95 E320
'97 CRV