Nymphaea ‘St. Louis Gold’

Further to my recent post.  So just what Nymphaeas are found in Dal Lake?
I have just come across a letter from the late Mary Briggs past Secretary of what is now the Botanical Society of Britain & Ireland.
I met Mary on her frequent visits to the main herbarium of the Natural History Museum in London.
She had undertaken a couple of treks in Kashmir and was interested in plants from the region (and many others parts of the world having led and incredible number of botanical tours for plant enthusiasts).  Arthur Chater (joint author of ‘An Enumeration of the Flowering Plants of Nepal’) kindly introduced us.   The letter represented comments after she had read my ‘Report on the Kashmir Botanical Expedition, 1983’.
She referred to the ‘naturalised water lily’ on Dal Lake – apparently it was Dr C.D.K. Cook* (then at Zurich) who provided the cultivar name ‘St. Louis Gold’ from her photos taken in 1974.
It seems this cultivar is a hybrid created by Georg H. Priny in 1956, the ‘pure’ (best) forms of which are described as citron yellow stars.  So it did not take long to be introduced onto Dal Lake.
This got me thinking, since I have already posted what Stewart thought of Nymphaea in the Kashmir Lakes, what about Hooker in FBI? 
Well, he recognised a Nymphaea alba var. kashmiriana.   Stewart gives this as a synonym of N.candida Presl.
Stewart observed that the Kashmir white water lilies need more study.  He had 3 names in his Catalogue yet in the field he only recognised only two, a large one, Nymphaea alba and a small one N.tetragona.
He wondered if N.candida (syn. N.alba var. kashmiriana) really was present?  The only record was Jacquemont’s collection of almost 2 centuries ago.
Has anyone better information?
*I note that Qaiser, author of Nymphaceae within ‘Flora of Pakistan’ acknowledges Professor Cook for going through the manuscript, see: http://www.efloras.org/florataxon.aspx?flora_id=5&taxon_id=10618 
Qaiser lists N.alba, candida, nouchalii, pubescens, tetragona – though adds little to what Stewart had stated nor seems to have addressed the issues raised; obviously, he would not have had access to fresh material from the Kashmir lakes in Indian territory and mentions nothing of cultivars.
Professor Cook was senior author of ‘Water Plants of the World: A Manual for the Identification of the Genera of Freshwater Macrophytes’.