Help with a B18A component!

I'm trying to regester my car (a '91 CRX with a B18A), but it failed emission (lucky bastards from FL). Now I'm trying to complete the gas recirculation system. From a visual inspection, I can only spot a missing component as outlined on the picture.

http://home.comcast.net/~srodrigu72/wsb/media/360365/site1_t.jpg

I can't find its purpose on my lousy Haynes Manual. Can somebody tell me what this valve(?) is for? To what it is connected to? Also, would you guys have a vacuum hose diagram for '92-'93 Integra LS?

Thanks in advance for your help.

BTW, this is my engine bay:

http://home.comcast.net/~srodrigu72/wsb/media/360365/site1002.jpg

Can you guys spot other missing emissions related components?