Cythna Lindenberg Letty, botanical artist, was the daughter of Walter Edward Letty and his wife Josina Christina Letty*, born Lindenberg. Her mother was also a botanical artist and gave Cythna lessons in watercolour painting during her childhood. The family resided for short periods in various Transvaal towns to enable her father to make a living. In 1914 Cythna completed her secondary education at the Girl's High School, Pretoria, but ill health prevented her from matriculating. After working as a governess on a farm near Pretoria for a while she trained as a nurse for a year, qualifying as a midwife. She then worked as a clerk in the South African Railways and moved to Cape Town from 1920 to 1924 to assist her brother-in-law, the physician Dr C. H. Bosenberg.
Letty was not formally trained as either a scientist or an artist. However, when she returned to Pretoria in 1925 she was appointed at the Onderstepoort Veterinary Laboratories to record in colour the typical appearance of post mortem specimens of animals that had died of various diseases. This interesting but gory work, later replaced by colour photography, was the first in which she was able to use her artistic talents. After two years she was transferred to the National Herbarium in the Division of Plant Industry, under Dr I. B. Pole Evans*, where she began to produce her outstanding paintings of African flowers. Her paintings were a tribute to both art and science, with delicate brushwork that gave exactitude and life to what she observed and that showed her dedication to those tiny details that make every flower unique. In due course she developed into one of South Africa's most distinguished and prolific botanical artists. She also described a few succulent species during the nineteen-thirties.
Letty resigned in 1938 to marry Oscar William Alric Forssman (grandson of O. W. A. Forssman, who was a brother of Chevalier M. J. F. Forssman*) and their son was born in 1940. However, she returned to her post in the National Herbarium in 1945 and worked there until her retirement in 1968. During her career she painted 740 plates for the journal Flowering Plants of Africa, plus many paintings and black and white illustrations for other publications such as "Trees and shrubs of the Kruger National Park" (Botanical Survey Memoir No. 26) and the journal Bothalia. She was the major artist with water colours and line drawings in The Stapeliae (1937, 3 vols) by A. C. White and B. L. Sloane and in The Succulent Euphorbiae (southern Africa) (1941, 2 vols) by A. White, R. A. Dyer and B. L. Sloane. Her book Wild flowers of the Transvaal (1962, with R. A. Dyer, I. C. Verdoorn and L. E. Codd) contained 145 colour plates and a contribution by her to the text. An Afrikaans translation was prepared by her cousin, Anna Rothman. When decimal coinage was introduced in South Africa she was asked to submit several floral motifs. Her designs for the 10c coin (depicting Aloe aculeata), 20c coin (Protea cynaroides and P. repens) and 50c coin (Strelitzia, Zantedeschia and Agapanthus) were accepted and the coins released in 1965. She also produced a floral design for the Rhodesian sixpence (Gloriosa virescence) which was released in 1964. After her retirement she produced a revision of the genus Zantedeschia (arum lily), which was illustrated with her own paintings and published in Bothalia in 1973. She also made a number of drawings of indigenous trees for the small books Trees of South Africa (1975) and More trees of South Africa (1980). During her career she collected about 500 plant specimens from various parts of South Africa and these are housed in the National Herbarium in Pretoria.
Letty also wrote poetry, which she regarded as an additional way of expressing her love for flowers. In 1981, when she was in her eighties, a selection of her poetry was published with 23 of her flower paintings under the title Children of the hours. In 1945 Volume 30 of Flowering Plants of Africa was dedicated to her "in grateful recognition of her signal service to South African botany and the art of botanical illustration". In 1966 she visited Europe and the United States when some of her paintings were included in an international exhibition in Pittsburgh. During a second overseas visit in 1970 she received the Grenfell silver medal from the Royal Horticultural Society for an exhibit of her paintings of Transvaal wild flowers in London. In 1974 the University of the Witwatersrand conferred on her an honorary Ll.D. degree in recognition of her lifelong outstanding contribution to botanical art. That same year the newspaper The Star recognized her as "woman of the year". She was elected a Fellow of the American Cactus Society in 1978. In 1981 the South African Association of Botanists awarded her a Certificate of Merit for her contribution to the advancement of botany in South Africa. The plant species Aloe lettyae (which she discovered in 1935) and Crassula lettyae were named after her by G. W. Reynolds and E. P. Phillips* respectively.
