Gowan Coningsby Clark, engineer and entomological illustrator, was the son of Colonel Cresswell Clark, assistant general manager of the South African Railways. He received his schooling in Port Elizabeth and later at the Diocesan College (Bishops), Cape Town, and passed the matriculation examination of the University of the Cape of Good Hope in 1908. Continuing his studies at the University of London he qualified as a civil and electrical engineer and also excelled in sport. Upon his return to South Africa he was employed by the South African Railways as an engineer in the Eastern Cape, with his headquarters in Port Elizabeth, rising to system engineer. He held this position until his retirement in 1948. He served in both World War I (1914-1918) during which he was wounded and severely gassed, and World War II (1939-1945) during which he attained the rank of major.
Clark was interested in natural history from an early age, particularly in butterflies, which he collected and reared. His collection activities were facilitated by the fact that his railway work took him to many different places. These trips were often made by trolley and he usually carried an insect net and other necessities for collecting, including a mosquito net spread out over the front of the trolley from which he picked off specimens at every stop. He was in particular interested in the life-histories of South African butterflies, breeding them out from the eggs and tending them right through to the adult stage, painting each stage with remarkable precision and meticulous attention to detail. He may have been motivated by, among others, the lack of reliable information on the early developmental stages of local butterflies during the nineteen-thirties. He was an accurate observer with an exceptional skill in water-colour painting, which he may have inherited from his mother who was a miniature painter. Eventually he produced complete life-history paintings of some 250 species plus many drawings of caterpillars that had died or been parasitized. Each completed life-history comprised up to 25 different paintings showing the egg, the various larval instars, the pupa and the adult, plus important details of the stages in greater magnification. Detailed notes on the appearance, behaviour and developmental tempo of the various stages were provided with each series of paintings. Some of his work was published in some 15 short papers, most in the Journal of the Entomological Society of Southern Africa between 1940 and 1964, but the bulk of his paintings appeared in several books by him and others: The butterflies of southern Africa (G. van Son, 4 volumes, 1949-1979, 125 plates of Papilionidae, Pieridae and Nymphalidae), Life histories of the South African Lycaenid butterflies (G. C. Clark and C. G. C. Dickson, 1971, 125 plates of Lycaenidae), and Pennington's butterflies of southern Africa (edited by C. G. C. Dickson and D. M. Kroon, 1978, 38 plates of Hesperiidae). His life-history studies of Lepidoptera have been described as unequalled in the world (Van Son, 1964).
Clark became a foundation member of the Entomological Society of Southern Africa in 1937. In recognition of his outstanding contributions to entomology he was awarded the Senior Captain Scott Memorial Medal by the South African Biological Society in 1948. After his retirement he joined the staff of the Port Elizabeth Museum, serving as acting director for over a year. He also continued his collection activities with several grants from the Council for Scientific and Industrial Research. During these years he produced a series of about a hundred wood carvings of South African marine fishes, including the Coelacanth, for the museum. These specimens were painted with his invariable meticulousness. He also spent several years of his retirement attempting a new classification of the Lepidoptera, based on larval features.
Clark was a retiring man who quietly pursued his hobby and shunned publicity. In 1920 he married Mary Jane McCracken, who died in 1922. Four years later he married Norah Williams. He had one son.
