Legend symbol too large

I've added a new feature layer to an Essentials site in 4.6.1.  This layer is in its own feature service and I've set special permissions to view it to only logged in users.  The problem is that it is showing in Essentials with a dot that is much bigger than the symbol in the feature service.  It's displaying OK in the map: the large dot is only a problem in the layer list and the legend.  I've not set any special settings in the layer to request that it be shown larger in the legend, so this is a real mystery.  This is using the HTML5 Viewer 2.7.0.