Seedling handedness has been studied in 76 genera and 137 species of of the Fabaceae out of which 35 genera and 78 species exhibit handedness. Its presence is more common or sporadic in some tribes and completely absent in other tribes. The taxonomic implications of this character is discussed. The possible causes for the existence of seedling handedness are discussed.

Seedling handedness with regard to first seedling leaf above the coleoptile has been studied in 67 genera and 93 species spread over 11 tribes of Gramineae. In general the tribes Paniceae, Andropogoneae, Festuceae, Hordeae, Aveneae, Bambuseae, Oryzeae and Chlorideae show seedling handedness whereas it is absent in Agrostideae, Phalarideae and Poaceae. Some tribes contain species that show handedness. Seedling handedness may be used for taxonomic purposes for delimiting the various tribes of Gramineae.

Seed morphology of 6 species ofNigella L. (Ranunculaceae) viz.,N. sativa L.,N. hispanica L.,N. arvensis L.,N. orientalis L.,N. nigellastrum (L) Willk. andN. integrifolia Regel, was studied utilising the light and scanning electron microscope to determine the significance of testa features as taxonomic characters. An artificial key based on spermoderm features is proposed to delimit the species studied. The present study supports the treatment ofN. integrifolia Regel as a monotypic genusKomaroffia integrifolia (Regel) Periera.

Seeds ofBiophytum vizB. helenae, B. intermedium, B. petersianum, B. reinwardtii andB. sensitivum are brownish, small (0·87 to 1·63 mm long), tuberculate and show distinct orientations of ridges and furrows and crystalliferous epidermal cells. On the basis of these characters a key is proposed to delimit the five species ofBiophytum.

Nectar composition (sugars and amino acids) of 100 species representing 83 genera from 34 families of angiosperms have been studied. The distribution of the 3 common sugars viz., sucrose, fructose and glucose in nectars of the species studied can be broadly divided into 6 types, based on the presence or absence of any one of the sugars viz sucrose-glucose-fructose, sucrose-glucose, sucrose-fructose, glucose-fructose, glucose and sucrose types with some variations. α-Amino acids were processed in 85 species. Distribution of amino acids was studied in some species and was found to be useful in detecting flower visitors.