Greg, it appears that Gary has found it - good job Gary. However, and for your information, in the 2210 technical manual diagram that I have, in comparison to the diagram that Gary has, it is called a "Breather Pipe", not a transaxle vent. I don't know the reason for this but the part is identical and in the same location on both diagrams.
I tried to locate it on my 2210, but it is obviously tucked away quite nicely and I was not able to find it.
Chuck