Volume 76, Issue 5
November 1972, pages 181-228
pp 181-193 November 1972
The four novelties which have come to light during the revisionary work of the genusFimbristylis are described in this paper out of which one belongs to the sectionTrichelostylis, two toFimbristylis and one toCymosae.
pp 194-200 November 1972
The results of the investigation carried out on pyroxene-garnet granulite which is closely associated with quartzite and ferruginous quartzite in the granitic rocks of Koppal area, Raichur District, Mysore State, have been described and discussed. Optical and chemical studies of light green pyroxene and pale pink garnet suggest that the clinopyroxene is ferrosalite with Tsch17Jd3Hd50Di30 (Yoder and Tilley, 1963) and the garnet is almandine rich with Alm72 Sp12 Py8 Gro8. On the basis of the distribution coefficient of Fe+2 and Mg+2 in co-existing pyroxene and garnet it has been concluded that the present mineral assemblage of the granulite is possibly due to regional metamorphism of ferruginous shale rich in lime, under conditions intermediate between glaucophane schist and granulite facies. Evidences are given in support of this conclusion.
pp 201-206 November 1972
A few terrestrial strips of the Burabalanga tidal estuary were studied both for their taxa and soil. The present study shows that there is a distinct change in the vegetational patterning and taxa composition from the stabilised estuarine shore towards the upland relief. With increasing distance from the estuarine shore line towards the upland the vegetation cover percentage decreased. Similarly the edaphic parameters show significant differences and show correlation both negative and positive in response to tidal rhythms within a broad topo-sequence. It is concluded that the cause for the sequential changes of taxa and soil correspond roughly to tidal floodings on the intertidal areas and the combined action of precipitation (climate) and local topography on the supratidal area.
pp 207-211 November 1972
The samples of AVCAT aviation fuel were periodically examined from the storage tanks with a view to ascertaining the extent of fungal contamination they harboured. It became possible to locate in some samples the presence ofCurvularia lunata (Wakker) Boedijn var.aeria (Batiota, Lima and Vasconcelos) Ellis, a fungal species having an ability to utilise hydrocarbons as a sole source of energy. The fungus grew copiously and decreased pH value of the fuel thereby rendering it unsuitable for use. Some aspects of the growth of this fungus in AVCAT fuel have been discussed here.
pp 212-218 November 1972
Studies on the digestion and absorption of sugars and proteins were made,in vivo, in two insects,Cybister tripunctatus asiaticus Sharp., a carnivorous aquatic beetle, andPoecilocerus pictus Fabr., a grasshopper.Cybister digested only starch;Poecilocerus digested maltose and sucrose. In both insects the foregut was the chief site of carbohydrate digestion. InCybister, glucose was absorbed by the anterior midgut; inPoecilocerus, gastric caeca was the site of absorption of glucose and fructose.
Protein digestion was first initiated in the foregut of both insects and completed in the midgut. Amino acids were absorbed by the posterior midgut region in both insects. The feeding habits of both insects had no influence on the determination of sites of digestion and absorption.
pp 219-220 November 1972
A single seedling produced by crossing a tetraploid tea plantCamellia sinensis (2n=60) withC. japonica (2n=30) resembled some of the “China-hybrids” and Gambod varieties of tea in cultivation. This suggests that natural hybrids between the two species must have occurred in the past.
pp 221-228 November 1972
Symptomatology, histopathology and etiology ofColletotrichum dematium (Pers. ex Fr.) Grove infection on leaves ofPeperomia tithymaloides A. Dietr. have been described. Isolations from diseased tissue yielded two strains, A and B, differing in certain cultural characters but not in the morphology of their conidia and condiiophores. Strain A is more virulent than strain B. Both strains infect uninjured host leaves but not stem. Adaxial epidermis is more susceptible to infection than abaxial epidermis. Wounding aids infection.
In vitro association of natural sectors or paired colonies of strains A and B leads to the development of densely crowded, large, heavily sporulating acervuli. Mycelia of strains A and B seem to anastomose, yielding conidia which on subculture show sectoring and segregation of the two parental strains.