Bought First Bike and one hose is disconnected...

[leedompat]

Just got my first bike. A 93 yamaha seca ii and I noticed that there in a hose behind the petcock that is just hanging there not connected anywhere. Bike runs fine and I dont know what the hose is for or where it connects too. It is thicker than all the other hoses and has a little black cannister attached. If someone could let me know where its suppose to connect to id really appreciate it. I cant find any info about it anywhere, I'll try to upload a pic of it with this post.