Plant identification - Assam/Bhutan

[Julia]

Hi can anyone help identify this lovely white flower from low country in Assam on the way to Bhutan

[Maggi Young]

Is it growing down a bank?

I wonder if it is some kind of Polygonatum, Julia?  In which case we need the advice of Aaron Floden.......

[WimB]

Hi Julia,

someone let me know that it is Pentasacme wallichi. You can find it in "Flowers of the Himalaya, A supplement" by Oleg Polunin.

[Maggi Young]

Pentasacme wallichii - well,  that's another new one to me!

Seems Edinburgh has a herbarium specimen, Julia, which may be of help to you
 http://elmer.rbge.org.uk/bgbase/vherb/bgbasevherb.php?cfg=bgbase/vherb/bgbasevherb.cfg&specimens_barcode=E00179674

http://books.google.co.uk/books?id=E8lAAAAAcAAJ&pg=PA159&lpg=PA159&dq=Pentasacme+wallichii.&source=bl&ots=iqGyC2zjEq&sig=REKiB1p3UJIl1X8MPbmU_ty1RBQ&hl=en&sa=X&ei=IGiYUurwF7SR7AbH44CoCw&redir_esc=y#v=onepage&q=Pentasacme%20wallichii.&f=false


Off now to read what Polunin says.......

[Maggi Young]

Here we are, from Stainton's supplement to Polunin and Stainton' s Flowers of the Himalayas....






Edit:
 I should have added -  it's in the Asclepiadaceae - the Milkweed family.

[Julia]

Thank you all very much.
Maggi its a new plant for me as well 
I am just going through my pictures and will post some more over the weekend
Julia

[Afloden]

 A friend saw this in Arunachal in September and sent me images of this. I had thought Cynanchum originally, but he found the Pentachasme ID as well. Probably the same person as the one who let Wim know.

 A very attractive plant! I hope to see it next spring while looking for Polygonatum.