How can I determine the type of a Port Group via C# API

I need to determine the type (ex "Virtual Machine Port Group" vs "VMKernel Port" vs ... as shown in vSphere Client) via the published C# (Web Service facade) API.   It s obvious this type is available as the vSphere client can show it but I do not see a way to get it via the API or Managed Object Browser.

Perhaps this is the result of my inexperience with the API but I looked at it well and did Google searches and found nothing.   I would expect this value to be part of some Managed Object (MO; e.g, HostPortGroup) or some data object obtained through a MO.  I do not see any such value.