Volume 88, Issue 4
July 1979, pages 253-330
pp 253-268 July 1979
Thirteen Indian spp. ofConiogramme (including a new speciesC. purpurea, a new combinationC. denticulato- serrata and a new recordC. serrulata) are described and their distribution indicated.
pp 269-275 July 1979
Morphology of the leaf epidermis of 32 species and one variety ofAsplenium is described. Epidermal cells on both the leaf surfaces are sinuous-walled except inA. adiantum- nigrum, A. bullalum, A. ensiforme, A. septentrionale andA. zenkeranum where the upper epidermal cells are straight-walled.A. griffithianum is the only species which possesses straight-walled epidermal cells on both the surfaces. In a majority of the species stomata are either anomocytic or both anomocytic and polocytic. However, in species likeA. erectum, A. fontanum, A. normale, A. trichomanes,A. unilaterale andA. zenkeranum only polocytic stomata are recorded. The stomata are largest inA. adiantum- nigrum and the smallest occur inA. caudatum.
pp 277-281 July 1979
On the basis of anatomical criteria the floral cup of Lauraceae can be regarded as appendicular, as the traces entering into the floral cup are morphologically compound, differentiated into tepal and stamen traces at higher levels. The ontogenetic studies also support this contention. The term Perigynous hypanthium is retained for the floral cup of Lauraceae as it is formed as a result of intercalary growth occurring underneath the region of perianth and androecium.
pp 283-291 July 1979
The laminae and petioles of two recently named species ofAlangium (A. circulare andA. grisolleoides) have been investigated. The placement ofA. circulare under Conostigma section of Bloembergen on exomorphic grounds is justified and strengthened on the basis of its leaf anatomy. Likewise the position and relationships ofA. grisolleoides that have been controverted is now accorded a place under Bloembergen’s section Rhytidandra based on its foliar anatomy and the preli minary observations on wood anatomy.
pp 293-301 July 1979
Correlative studies on changes in anatomical structures have been made in the first trifoliate leaves of pigeon pea (Cajanus indicus Spreng.) and cluster bean [Cyamopsis tetragonoloba (L) Taub.] as induced by NaCl salinity. Leaves of salt stressed plants are characteristically small, but often otherwise normal in appearance and are succulent. The succulence is mainly due to the increase in thickness of both palisade and spongy parenchyma. Palisade cells seemed to enlarge much more than the spongy parenchyma cells. The leaves further showed considerable reduced inter-cellular spaces, reduced dimensions of xylem vessels, increased thickness of xylem wall, increased cuticle thickness and increased number of chloroplasts. The relevance of these changes in structure and function has been discussed.
pp 303-308 July 1979
Apical application of cobalt chloride to female plants (50 or 100 μg/ plant) ofCannabis sativa caused drying of the shoot tip and formation of axillary branches. The latter bore male, reduced male and intersexual flowers, in addition to female flowers. Pollen in the flowers of altered sex were viable.
pp 309-316 July 1979
InHeuchera micrantha Dougl. the tapetum is secretory and its behaviour variable. The study of tapetum with reference to development and behaviour of meiocytes suggests a correlation between them. In a few sporangia meiocytes follow more than one way of development indicating that their behaviour is not totally controlled by the tapetum. Inner tangential walls of tapetal cells show thickening composed of sporopollenin-like substance. The thickening probably prevents transport of nutrients from tapetum to meiocytes resulting in hypertrophied tapetum and degeneration of meiocytes.
pp 317-319 July 1979
Malleola andamanka Balakr. and Bhargava, sp. nov. of Orchidaceae, discovered from Andaman Islands, is described with illustrations.
pp 321-325 July 1979
Somatic chromosome morphology and induced tetraploidy inPapaver somniferum L. variety Dhaturia has been studied. Detailed studies on total chromosome length, relative length and arm ratio have been made and presented.
pp 327-330 July 1979
The paper gives an illustrated account of a new grass, viz.G. normanii from Burma.