Histochemical studies in combination with selective extraction on the vestured pits of some Caesalpiniaceae members revealed that the vestures were free of lignin and cellulose, and were mainly composed of carboxylated polysaccharides.

Root and stem woods of 29 taxa of Caesalpiniaceae were studied in detail with respect to the crystal strands. Although the crystals were of Calcium oxalate nature, variations were recorded in the presence or absence and, if present, in the density of distribution, height, number of constituent cells and pattern of distribution (among other wood tissues) of the crystal strands. The true morphology of the crystal strand is also discussed.

RANJANI K., and KRISHNAMURTHY, M. V. 1988. The gelatinous fibres of Caesalpiniaceae. Can. J. Bot. 66: 394-399.Twenty-seven species of Caesalpiniaceae were studied to compare the gelatinous fibres of root and stem wood. Species that possessed gelatinous fibas in root wood also possessed them in stem wood, but only two taxa showed the reverse condition. Gelatinous fibres did not exhibit an organ-dependent specificity in their transectional distribution. In roots, the gelatinous fibres generally differentiated immediately after initiation of secondary growth, whereas in most stems they differentiated considerably after the onset of secondary growth. The positive correlation detected previously between the distribution pattern, as well as the number of gelatinous fibres, and the eccentricity of the stem or root could not be verified. Even perfectly noneccentric roots and stems showed variations in the distribution pattern and number of gelatinous fibres. In roots, generally, all fibres were gelatinous, whereas in stems both gelatinous and normal fibres were present and showed different distributional pattern. All three types of gelatinous fibres (convolute, thick, and intermediate) recognised by earlier workers and based on the gelatinous layer were observed in this family. Gelatinous fibres of this family formed lignified, partially lignified, and nonlignified gelatinous layers. Differences were also noticed in the relative thickness of the gelatinous layer. RANJANI K., and KRISHNAMURTHY, K. V. 1988. The gelatinous fibres of Caesalpiniaceae. Can. J. Bot. 66 : 394-399.Vingt-sept eseces de CQalpiniades ont 6tk Ctudikes dans le but de comparer les fibres gClatineuses du bois de la racine et de la tige. Les espkes ayant des fibres gklatineuses dans le bois de la racine les avaient aussi dans le bois de la tige, mais seuls deux taxons ont montr6 la condition contraire. Les fibres gklatineuses n'ont pas montd de spkcificitk dkpendante d'organe dans leur distribution sur le transecte. Dans les racines, les fibres gklatineuses se differenciaient en gknkld immfkliatement ap2s l'initiation de la caissance secondaire tandis que chez la majoritk des tiges elles ne se diffkrenciaient que quelque temps ap2s le debut de la cmissance secondaire. La codlation positive d k e l h pdcddemrnent entre le modhle de distribution et le nombre de fibres gatineuses et l'excentricitk de la tige ou de la racine n'a pu Ctre vkrifike. MCme les racines et les tiges parfaitement non-excentriques ont montn-5 des variations dans le modkle & distribution et le nombre de fibres gklatineuses. Chez les mcines en g6nkral, toutes les fibres ktaient gklatineuses, tandis que chez les tiges se retrouvaient et des fibres gklatineuses et des fibres n o d e s qui montraient des modbles diffkrents & distribution. Les tmis types de fibres gelatineuses (convolut6, kpais et intermtkiiaire) reconnus par d'autres et basks sur la couche gklatineuse, ont kt6 observks dans cette famille. Des couches gklatineuses lignifihs, partiellement lignifi6es ont kt6 observks dans l...

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