the former Economic Garden, and plant nurseries. Due to the high upkeep of the zoo at the gardens, in 1903, the colonial government decided to sell all the animals and birds and shut it down. More building installations at the garden included E.J.H Corner House in 1910 and Holttum Hall in 1921. This was also the period when Singapore's national flower, the orchid Hybrid Vanda Miss Joaquim, was founded, which was part of the achievement of the pioneering of orchid hybridisation by Professor Eric Holttum, director of the Gardens from 1925 to 1949. His techniques led to Singapore being one of the world's top centres of commercial orchid growing. Presently, it has the largest collection of tropical plant specimens. 1942–1945 During the Japanese occupation of Singapore from 1942 to 1945, Hidezo Tanakadate (田中館秀三), a professor of geology from Tohoku Imperial University, learned of the possibility that the Gardens and Museum might be looted due to the occupation, and negotiated directly with general Tomoyuki Yamashita to gain control of the Singapore Botanic Gardens and the Raffles Museum. At the beginning of the occupation, he ensured that no looting occurred in the Gardens and the Museum. Both institutions continued to function as scientific institutions. Holttum and Edred John Henry Corner were interned in the Gardens and instructed to continue their horticultural work. The Japanese government and army were unwilling to fund the institutions, however, and Tanakadate had to pay for maintenance and staff salaries from his own pocket. The Gardens was also renamed as Shōnan Botanic Gardens (). Tanaka returned to Japan in July 1943, and Dr. , a retired professor of botany from the Kyoto Imperial University and secretary-general of the Imperial Japanese Army's Malayan military administration department's general affairs department, was appointed director to the Gardens and Museum, posts he held until the end of the war. 1945–1986 After the war ended, the Gardens was handed back to the control of the British in September 1945, and Koriba was made a prisoner of war. Corner negotiated for Koriba's release with the British command, citing his contributions to protecting the Gardens, but he chose to remain in custody alongside his countrymen until his release in January 1946. Murray Ross Henderson, curator of the Herbarium before the war, succeeded Holttum as director from 1949 to 1954. Eventually the Gardens played an important role during the "greening Singapore" campaign and Garden City campaign