The book cover shows Austen without her night-cap

"She was not much of a looker," said Helen Trayler, managing director of publisher Wordsworth Editions.

Publishers traditionally use a portrait of Austen painted by her sister but Wordsworth have added make-up, hair extensions and removed her cap.

The book is a new edition of a memoir by Austen's nephew.

The book cover was adapted from this portrait housed at the National Portrait Gallery

"I know you are not supposed to judge a book by its cover. Sadly people do. If you look more attractive, you just stand out more," said Ms Trayler.

The original painting by Cassandra Austen, which hangs in the National Portrait Gallery in London, is thought by some scholars to be the only authentic portrait of the celebrated author.

But another portrait said to be of Austen is going up for auction at Christie's in New York on 19 April and is expected to fetch between $400,000 (£203,000) and $800,000 (£406,000).

The oil painting, known as the Rice Portrait of Jane Austen after a former owner, Henry Rice, has been the subject of debate after some scholars said it was not authentic.

The oil painting being auctioned is by society artist Ozias Humphry

The painting by Ozias Humphry first came to prominence in 1884 when it appeared on the front of a first edition of Jane Austen's letters collection.

Some scholars have argued that the costume Austen is wearing in the picture dates to about 1805, making her about 30 when it was painted - earlier experts thought the painting dated to 1788 or 1789, making Austen about 14.

This has led to doubts about the portrait in some quarters, although a number of academics in recent years have supported the original attribution, as does auction house Christie's.

Jane Austen's novels include Pride and Prejudice, Sense and Sensibility, Emma and Mansfield Park.