93 Honda Accord 10th Anv. Coolant leak down behind the engine.

Im having a leak coming for a odd part down below/behind the engine.
There is a small hose (1inch-1 1/4inch in diameter) that runs off the
left side of the engine down to the the lower left, somewhat behind the
left wheel. Basically directly under the air filter hose part that
runs along top, underneath the hood. This little part from a above
looks like a metal box that the small hose decribed connects to. I
viewed this part from under the vehicle the best I could and it seemed
that this part was the problem. This part im trying to descirbe
almost looked like a plastic box from below, and had small squares in
it, almost like a waffle.

My question is about this part. What is this part? I need to know a
name so I can replace it. Also, is it likely that this could be
leaking? It seems that the leak is coming from it but I cant say Im
100% positive. I did replace that small hose attached to it (described
above) thinking it was the problem but it wasnt.

Any information would be great. Maybe a link even to the coolant
system schematics (sp?) for my model of vehicle.

Alex