TypeExtensions.cs

public static class TypeExtensions
{
    public static bool IsAssignableToGenericType(this Type givenType, Type genericType)
    {
        var interfaceTypes = givenType.GetInterfaces();

        if (interfaceTypes.Any(it => it.IsGenericType && it.GetGenericTypeDefinition() == genericType))
        {
            return true;
        }

        if (givenType.IsGenericType && givenType.GetGenericTypeDefinition() == genericType)
        {
            return true;
        }

        var baseType = givenType.BaseType;
        if (baseType == null)
        {
            return false;
        }

        return IsAssignableToGenericType(baseType, genericType);
    } 

    public static bool IsEnumeration(this Type givenType)
    {
        return givenType.IsAssignableToGenericType(typeof(Enumeration<>));
    }
}