Thanks for your suggestions everyone.

I had exported and re-imported the model, so I don't think that was the problem.  I even deleted the offending polygons, recreated that part of the model, and started over with a new uv map - same results.

I think part of the problem is that I don't yet understand splitting, merging, and stitching the uv's.  I think part of this probem might be that I used cylinder mapping, and that row of polygons (and part of the collar) are where the 'caps' might be. 

 

I plan to start over with a new shirt.  This time I will create material zones to try to make it easier to separate the map zones.  Hopefully, I'll get better.

Thanks again.