The fine structural aspects of certain budlike protrusions associated with helical thickening near pits on the vessel wall of Ligustrum lucidum (Oleaceae) have been studied. In addition unusual thickenings of the intervascular pit membranes similar to torus-like structures are described.

No abstract

Jungermanniales Acrogynae. II. Lejeuneaceae

Jungermanniales Acrogynae. I.

This study describes the wood and bark of Prockia crucis L., Flacourtiaceae. Aside from quantitative and histometric data about the secondary xylem, illustrations of wood and bark are furnished. The wood of Prockia crucis presents characteristic features, conforming to the typical structure of the Flacourtiaceae family. Very tenuous spiral thickenings in vessel walls, as wall as the occasional presence of calcium oxalate chambered crystals in fibers were observed for the first time in the genus Prockia. The presence of sclerenchymatous elements, such as fibers, sclereids and crystalliferous sclerotic cells with calcium oxalate, monocrystals, macles and druses, was observed in the pholoem.