|The citron is a large fragrant citrus fruit with a thick rind, botanically classified as Citrus medica by both the Swingle and Tanaka botanical name systems. It is one of the four original citrus fruits (the others being pomelo, mandarin and papeda), from which most other citrus types developed through natural hybrid speciation or artificial hybridization.
Citrus medica is a slow-growing shrub or small tree that reaches a height of about 8 to 15 ft (2 to 5 m). It has irregular straggling branches and stiff twigs and long spines at the leaf axils. The evergreen leaves are green and lemon-scented with slightly serrate edges, ovate-lanceolate or ovate elliptic 2.5 to 7.0 inches long. (Source: Wikipedia)