Lettice Digby (31 July 1877 – 27 November 1972) was a British

cytologist Cell biology (also cellular biology or cytology) is a branch of biology that studies the structure, function, and behavior of cells. All living organisms are made of cells. A cell is the basic unit of life that is responsible for the living an ...

botanist Botany, also called plant science, is the branch of natural science and biology studying plants, especially Plant anatomy, their anatomy, Plant taxonomy, taxonomy, and Plant ecology, ecology. A botanist or plant scientist is a scientist who s ...

and

malacologist Malacology, from Ancient Greek μαλακός (''malakós''), meaning "soft", and λόγος (''lógos''), meaning "study", is the branch of invertebrate zoology that deals with the study of the Mollusca (molluscs or mollusks), the second-largest ...

. Her work provided the first demonstration that a fertile

polyploid Polyploidy is a condition in which the biological cell, cells of an organism have more than two paired sets of (Homologous chromosome, homologous) chromosomes. Most species whose cells have Cell nucleus, nuclei (eukaryotes) are diploid, meaning ...

hybrid Hybrid may refer to: Science * Hybrid (biology), an offspring resulting from cross-breeding ** Hybrid grape, grape varieties produced by cross-breeding two ''Vitis'' species ** Hybridity, the property of a hybrid plant which is a union of two diff ...

had formed between two cultivated plant species.

Education and personal life

Digby was born on 31 July 1877 in Chelsea, London, UK. She was the second of the four children of Sir

Kenelm Edward Digby Sir Kenelm Edward Digby, (9 September 1836 – 21 April 1916) was a British lawyer and civil servant. He was Permanent Under-Secretary of State at the Home Office from 1895 to 1903. Biography Digby was born in Wotton-under-Edge in Gloucesters ...

and Hon. Caroline Strutt who had married on 30 August 1870. She studied at the

Royal College of Science The Royal College of Science was a higher education institution located in South Kensington; it was a constituent college of Imperial College London from 1907 until it was wholly absorbed by Imperial in 2002. Still to this day, graduates from t ...

. By 1907 she was living in Kingsford, Colchester, and she died in

Colchester Colchester ( ) is a city in northeastern Essex, England. It is the second-largest settlement in the county, with a population of 130,245 at the 2021 United Kingdom census, 2021 Census. The demonym is ''Colcestrian''. Colchester occupies the ...

, Essex, UK on 27 November 1972.

Scientific career

Digby was active in research within both botany and malacology, where she applied the technologies of

cytology Cell biology (also cellular biology or cytology) is a branch of biology that studies the structure, function, and behavior of cells. All living organisms are made of cells. A cell is the basic unit of life that is responsible for the living an ...

. Her application of cytology to the Kew primrose (''Primula kewensis'') provided the first example of a polyploid hybrid to be recorded. This fertile polyploid species arose through

chromosome A chromosome is a package of DNA containing part or all of the genetic material of an organism. In most chromosomes, the very long thin DNA fibers are coated with nucleosome-forming packaging proteins; in eukaryotic cells, the most import ...

doubling in an otherwise infertile hybrid. The fertile

with 36 chromosomes was formed at

Royal Botanic Gardens, Kew Royal Botanic Gardens, Kew is a non-departmental public body in the United Kingdom sponsored by the Department for Environment, Food and Rural Affairs. An internationally important botanical research and education institution, it employs 1,10 ...

among infertile hybrids between ''P. verticillata'', originating from Africa and Asia, and ''P. floribunda'', from the Himalayas. The hybrids had been noticed in 1899 by staff at Kew, particularly Frank Garett, and were awarded a First Class certificate at a

Royal Horticultural Society The Royal Horticultural Society (RHS), founded in 1804 as the Horticultural Society of London, is the UK's leading gardening charity. The RHS promotes horticulture through its five gardens at Wisley (Surrey), Hyde Hall (Essex), Harlow Carr ...

meeting in 1900. They were large plants with attractive flowers. The lack of fertile seeds despite repeated efforts at crossing the parents was a problem until some were obtained in 1905. Digby was thus able to compare both fertile and infertile hybrids. ''P. kewensis'' continued to be cited into the 21st century as an example of a new species originating from human activities. Digby made measurements of chromosome length, width and number during

meiosis Meiosis () is a special type of cell division of germ cells in sexually-reproducing organisms that produces the gametes, the sperm or egg cells. It involves two rounds of division that ultimately result in four cells, each with only one c ...

in both plants (such as smooth hawk's-beard ('' Crepis virens'') and ''

Primula ''Primula'' () is a genus of herbaceous plant, herbaceous flowering plants in the family (biology), family Primulaceae. They include the primrose (''Primula vulgaris, P. vulgaris''), a familiar wildflower of banks and verges. Other common specie ...

'') and animals such as ''

Helix pomatia ''Helix pomatia'', known as the Roman snail, Burgundy snail, or escargot, is a species of large, air-breathing stylommatophoran land Snails, snail native to Europe. It is characterized by a globular brown shell. It is an edible species which comm ...

'' and ''

Homarus gammarus ''Homarus gammarus'', known as the European lobster or common lobster, is a species of clawed lobster from the eastern Atlantic Ocean, Mediterranean Sea and parts of the Black Sea. It is closely related to the American lobster, ''H. americ ...

''. She collaborated with John B Farmer and John E S Moore, early investigators of the units of

heredity Heredity, also called inheritance or biological inheritance, is the passing on of traits from parents to their offspring; either through asexual reproduction or sexual reproduction, the offspring cells or organisms acquire the genetic infor ...

. She worked with Farmer on chromosome counts of the

intergeneric hybrid In biology, a hybrid is the offspring resulting from combining the qualities of two organisms of different varieties, subspecies, species or genera through sexual reproduction. Generally, it means that each cell has genetic material from two dif ...

fern Schneider’s Polypody, ''

Polypodium ''Polypodium'' is a genus of ferns in the family Polypodiaceae, subfamily Polypodioideae, according to the Pteridophyte Phylogeny Group classification of 2016 (PPG I). The genus is widely distributed throughout the world, with the highest ...

schneideri''. This was not known to have parents from different genera at the time, and the technology of the time made precise chromosome visualisation in ferns difficult. She analysed the structure and

taxonomy image:Hierarchical clustering diagram.png, 280px, Generalized scheme of taxonomy Taxonomy is a practice and science concerned with classification or categorization. Typically, there are two parts to it: the development of an underlying scheme o ...

of some

gastropods Gastropods (), commonly known as slugs and snails, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, freshwater, and from the land. Ther ...

Moore had collected in

Lake Tanganyika Lake Tanganyika ( ; ) is an African Great Lakes, African Great Lake. It is the world's List of lakes by volume, second-largest freshwater lake by volume and the List of lakes by depth, second deepest, in both cases after Lake Baikal in Siberia. ...

. This was at a time when the relationship of chromosome structures to inheritance was under active investigation. In addition, after the success of genetic studies in

Drosophila ''Drosophila'' (), from Ancient Greek δρόσος (''drósos''), meaning "dew", and φίλος (''phílos''), meaning "loving", is a genus of fly, belonging to the family Drosophilidae, whose members are often called "small fruit flies" or p ...

, the selection of additional model organisms was needed to ascertain whether these findings could be generalised to all plants and animals. Smooth hawk's-beard was proposed as another model organism. Digby had studied its

, determining that it had 3 pairs of chromosomes. Her work on the structure of chromosomes, their changes during mitosis and meiosis and their relationship to the units of heredity was early support for the chromosome theory of inheritance. Digby spent some of her career at the Biological Laboratory, Royal College of Science and at the

Jodrell Laboratory Kew Gardens is a botanical garden, botanic garden in southwest London that houses the "largest and most diverse botany, botanical and mycology, mycological collections in the world". Founded in 1759, from the exotic garden at Kew Park, its li ...

, Royal Botanic Gardens, Kew. In 1903 she exhibited her work at the

Royal Society The Royal Society, formally The Royal Society of London for Improving Natural Knowledge, is a learned society and the United Kingdom's national academy of sciences. The society fulfils a number of roles: promoting science and its benefits, re ...

's ladies' soireé. During the

First World War World War I or the First World War (28 July 1914 – 11 November 1918), also known as the Great War, was a World war, global conflict between two coalitions: the Allies of World War I, Allies (or Entente) and the Central Powers. Fighting to ...

she spent time working as a laboratory assistant at the South African Military Hospital in Richmond Park, London. In 1919-1920 she was working with E.E. Glynn of

University of Liverpool The University of Liverpool (abbreviated UOL) is a Public university, public research university in Liverpool, England. Founded in 1881 as University College Liverpool, Victoria University (United Kingdom), Victoria University, it received Ro ...

to study

pneumococcal ''Streptococcus pneumoniae'', or pneumococcus, is a Gram-positive, spherical bacteria, alpha-hemolytic member of the genus ''Streptococcus''. ''S. pneumoniae'' cells are usually found in pairs (diplococci) and do not form spores and are non mo ...

infections using serological and bacteriological methods, financed by the Medical Research Council.

Awards

* She was elected a member of the Malacological Society of London in 1903. * She was elected an ordinary fellow of the Royal Microscopical Society in 1918.

Publications

Digby was author or co-author of at least 8 scientific papers: * J. B. Farmer, J. E. S. Moore and Digby L. (1902
On the cytology of apogamy and apospory - 1 preliminary note on apogamy
''Proceedings of the Royal Society of London'' 71 (475) 453-457 * Digby, L. (1902
On the structure and affinities of some gastropods from Lake Tanganyika belonging to the genera ''Chytra'' and ''Limnotrochus'' (communicated by Prof G. B. Howes, Sec L.S. and read on her behalf by Mr J. E. S. Moore).
''Linnean Journal of Zoology'' 28 434 - 442 * Digby, L. (1902
On the Nyassa vivipara and its relationship to Neothauma.
Read at the Linnean Society 20 February 1902. *Digby, L. (1903) Preliminary note on the anatomy of the genus ''Cataulus''. ''Proceedings of the Malacological Society of London'' 5 261 * Digby, L. (1905
On the cytology of apogamy and apospory. II. Preliminary note on apospory
''Proceedings of the Royal Society of London Series B'' 76 (512) 463-467 * J. Bretland Farmer and L Digby (1907) Studies in apospory and apogamy in Ferns. ''Annals of Botany'' 21 (81-84) 161-199 * Digby, L. (1909) Observations on 'chromatin bodies' and their relation to the nucleolus in ''Galtonia candicans'', Decsne. ''Annals of Botany'' 23 (89-92) 491-499 * Digby, L. (1910) The somatic, premeiotic, and meiotic nuclear divisions of ''Galtonia candicans''. ''Annals of Botany'' 24 (93 - 96) 727-757 * Digby, L. (1912) The cytology of Primula kewensis and of other related primula hybrids. ''Annals of Botany'' 26 (101-4) 357-U111 * Digby, L. (1914) A Critical Study of the Cytology of ''Crepis virens'' Arch. Zellf. 12 97-146 * J. B. Farmer and Digby L. (1914) On dimensions of chromosomes considered in relation to phylogeny ''Proceedings of the Royal Society of London Series B'' 205 * Digby, L. (1919) On the archesporial and meiotic mitoses of Osmunda ''Annals of Botany'' 33 (130) 135-172

References

{{DEFAULTSORT:Digby, Lettice 1877 births 1972 deaths British malacologists British women botanists English botanists People from Chelsea, London Scientists from London Botanists from London Alumni of the Royal College of Science People from Colchester 19th-century British botanists 19th-century English scientists 19th-century English women scientists 20th-century British botanists 20th-century English women scientists