Susan Greenfield, the Oxford brain scientist, has not been shortlisted for nomination to the country's leading scientific body after a whispering campaign against her.
Baroness Greenfield has been singled out by some fellows of the Royal Society who have said privately that they would considering resigning if she was elected.
Although Lady Greenfield is widely admired as a communicator of science - she has presented television programmes on the brain - some scientists have suggested that her research is too insubstantial for her to be a prestigious Fellow of the Royal Society.
Her media activities and high profile as the first female director of the Royal Institution have been resented by some senior scientists, who believe that her actions are motivated by self-promotion.
A spokesman for the Royal Society refused to comment in detail on a report today in the Times Higher Education Supplement which says that fellows have rejected her nomination for this year's intake.
"The candidate in question was considered by the relevant sectional committees at the meetings in January and the decision was taken then that she, along with the majority of other candidates, would not be placed on the long-list for election this year," the spokesman said.
The election of 44 new fellows will take place at the end of May and the shortlist has been drawn from a total of 535 candidates who will remain eligible for future election for a further seven years.
Media reports first appeared in February suggesting that some fellows opposed to Lady Greenfield's nomination would resign if she was elected but this did not play a role in the decision to exclude her from the shortlist, the spokesman said.
"The sectional committees held meetings between 13 and 22 January 2004 to make a preliminary assessment of the relative strengths of candidates and each committee produced a long-list," he added.
"The majority of candidates were ruled out during the preparation of these long-lists, which occurred well before the publication on 5 February of the first media reports about Baroness Greenfield," he said.
Lady Greenfield declined to comment yesterday on the reports of her failed nomination. However, in a statement issued in February, she denounced the anonymous fellows who had criticised her nomination.
"It is a great pity that those who do not have the courage to identify themselves can make unsubstantiated criticisms of my science and my activities in public communication," her statement read.
Lady Greenfield, 53, became professor of pharmacology at Oxford University in 1996 and was made director of the Royal Institution, which was founded by Michael Faraday, in 1998. She became a "people's peer" in 2001 and has written several popular science books.
She had attracted wide media coverage, as much for her penchant for short skirts and high heels, as for her science. She once said that her greatest wish is to have a "bum like Kylie Minogue's".
Another, less famous female neuroscientist, Nancy Rothwell of Manchester University, has reached the shortlist. The Royal Society said it is trying to improve the proportion of female fellows, who constitute just 4.3 per cent of its 1,244 fellows.