Abstract

                                The familiar forms of castor, Ricinus communis L. are the cultivated varieties raised either dry or irrigated. Distinct from these there also exist certain perennial tree types of which little is known. Mention is made of the perennial variety in most of the literature on castor, but in no instance has an attempt been made to distinguish it from the other types or yet to describe it fully. Popova (3), the Russian worker, makes mention of a wild type of castor growing in India and elsewhere but does not say whether it is a perennial type. Hil'tebrandt (2) recognises the perennial form but does not describe it. Bahl (1) has it that in tropical countries the castor plant reaches the dimensions of a small tree and may attain a height of 20' to 30 or more, with a stout trunk and branches. In cooler countries, he adds, it becomes a shrub or bush 8' to 12' high and in localities where frosts occur it is a herbaceous perennial. There are numerous other refer- ences also which go to show, that, though the existence of a distinct variety perennial in habit and growing into a tree has been known, no detailed study has so far been made of this variety. In this paper an attempt has been made to describe in detail the pere- nnial types collected from various parts of the Madras Presidency and indi- cate the similarities and differences between the cultivated and perennial varieties of castor. The agricultural utility of the tree form has also been discussed as it is felt that some of the economic forms may with advantage be brought under cultivation.

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