Stella, born on the 9th January 1927 in Croydon, Surrey, was the youngest daughter of the eminent geologist George MacDonald Davies. His first wife had died leaving him with one daughter, Margaret, subsequently his second wife, Agnes, gave birth to John Grant Davies (the astronomer) and Stella Madeline Davies.
In 1932 the family moved to a house in Sanderstead, Surrey where, after the death of their parents, Stella and her sister Margaret continued to live until they moved into a retirement home in 2005. Stella attended Croydon High School for Girls (GPDST) and went with the school when it was evacuated to Bradden in Northamptonshire during WW2. After finishing her schooling Stella went up to Cambridge where she studied Natural Sciences at Girton College.
After university Stella worked in the Natural History Museum, London, as an assistant in the Zoology Department. She joined in January 1948 and worked in the Annelid section, with Maurice Burton and Norman Tebble, leaving in April 1951. Stella then had a teaching job in Yorkshire. At one period Stella rode a motorcycle, but she never drove a car. In later life she once said that she was too nervous to drive a car, but would have enjoyed the freedom it could have given her.
For many years Stella worked at St Margaret's, a school in Croydon for children with cerebral palsy, where she was a house parent. She was particularly involved with caring for the physical needs of the children rather than with the teaching side of the school and she stayed in touch with some of the children until her death. She also helped with the Winged Fellowship Trust, now renamed Vitalise, a charity providing holidays for disabled people, and continued to accompany groups until she was in her seventies.She was held in great affection by the Trust and news of her death caused much sadness.
Stella was a longstanding member of the two British societies devoted to the study of molluscs, namely the Malacological Society of London and the Conchological Society of Great Britain and Ireland. Stella herself was internationally well known as a specialist in the biology of slugs. She was very generous in her help to other workers on slugs, particularly in the rest of Europe. Her generally quiet demeanour would become animated and forthright when discussing her favourite animals, which she regularly brought to meetings to show the extent of variation that occurred in siblings. In two important papers, based on meticulous observations made during a period of over 60 years of the slugs in her garden in Croydon, and supported by long-term breeding experiments, she was able to demonstrate that one of our most common horticultural pests, Arion hortensis, was actually an aggregate of three species (Davies, 1977), one of which she described as new to science (Davies, 1979), a conclusion supported by recent DNA techniques. The initial paragraph of the first of these papers is instructive, and sums up much of Stella's philosophy: 'The study of an animal as familiar and supposedly well-known as Arion hortensis is far too easily neglected by the ordinary naturalist. The observations described in this paper began by accident and continued in ways suggested by the slugs themselves'. Her views on the separation of closely related species were ahead of her time.
As a colleague commented "What was impressive was the way in which she related her detailed, original work on the genital anatomy of Arion with equally original observations on the breeding cycles of the different taxa that she established. This came from the most careful recording over many years, in her garden and elsewhere - natural history in the best sense." However, "getting her to publish [her findings] was quite another matter. extracting manuscripts from her was a real struggle, and then she would insist on having them back for rewriting and refining. It is a pity that her perfectionism did not allow her to publish more, especially on the larger Arion species."
Apart from her interest in natural history Stella also had a keen interest in family history. Amongst her papers were a number of trees for different branches of the family and her niece, Kate, has taken these over to continue Stella's interest in genealogy. For someone of her generation she was also very aware of ecological issues and this was well known within her family. Her brother John's son and daughter, Richard and Kate, wrote: "She would talk about water use in the SE of England and the need to use energy sparingly etc.Her interest in the water cycle in the SE is no doubt related to her father's professional interest in the subject; he wasgeologist and I believe he wrote a paper on the subject.In the residential home she would regularly complain about the wasteful use of resources.This was of course after 2005.But she recycled as much as possible for as long as [any] other family members can remember."
"We, that is John's family, have memories of holidays with Stella.If she visited our home she would enjoy being in the garden and helping with the gardening.She was a keen gardener at the family home in Sanderstead.I think she was probably keener on the vegetables than flowers.On family holidays Stella would enjoy going on walks with us.But she was forever stopping to turn over logs and stones and see what she could find, often putting the creatures in her pockets for later study.Stella would sometimes ask other family members to send her slugs from their holidays or where they were living at the time.I [Richard] occasionally did this.Another memory from Christmas holidays (Margaret and Stella often joined us at that time) is of Stella spending time doing large jigsaw puzzles.was always ready for a cup of tea, and a second and a third ...."
"Stella was very shy with strangers.But once she was ona favourite theme - slugs or family history for example - she would have plenty to say and it could be hard to get a word in.Sometimes, both in conversation and in her letters, she would abruptly start a new subject and one wondered what might have triggered it.I was only really aware of this in latter years but possibly she had been like this earlier and I had not noticed.The last letter I received from her told me in some detail about the history of Marmite, a subject that we had never previously discussed other than perhaps to ask for it to be passed across the table."
Stella was a unique and somewhat eccentric person, but she was much loved and respected by her family, friends and her many malacological colleagues.
Her natural history papers were left to the Conchological Society of Great Britain and Ireland.
Davies, S.M. 1977. The Arion hortensis complex, with notes on A. intermedius Normand (Pulmonata: Arionidae). Journal of Conchology, 29, 173-187.
Davies, S.M. 1979. Segregates of the Arion hortensis complex (Pulmonata: Arionidae), with the description of a new species, Arion owenii. Journal of Conchology, 30, 123-127.
[This obituary was written with the help of Richard and Kate Davies, Nick Evans, Michael Kerney, Peter Mordan, John Peake and Richard Preece.]