Volume 67, Issue 1
January 1968, pages 1-34
pp 1-7 January 1968
Some known standard salines for molluscs were found unsuitable for maintaining the heart ofPila in vitro. A new saline forPila has been devised keeping in view the ionic composition, pH and osmotic pressure of blood ofPila. A saline having the composition of blood was not found suitable for maintaining isolated heart ofPila but reduction of percentage of potassium made it so. The osmotic pressure was adjusted with addition of glucose which also provides energy. Changes of pH between 5 and 8·5 did not have an effect on the heart-beat ofPila. It was suggested that a saline containing only the principal ions of blood was not suitable because other trace and organic substances present in the blood were perhaps playing an important role in the regular beating of the heart. Adjustment in the proportion of different ions and addition of glucose did partly compensate for the absence of these substances.
pp 8-17 January 1968
The present paper deals with the anatomical studies in the leaf ofClerodendrum splendens G. Don. The extra-floral nectaries are patelliform and originate from a single epidermal papillate cell. They secrete sugary fluids. The diffuse type of brachysclereids and the spheroidal crystalliferous sclereids occur in the mesophyll, mid-rib region of the leaf and the ground tissue of the petiole. The vascular bundles in the mid-rib region and the petiole are arranged in a ring. The phloem does not form a continuous arc. The smaller vascular bundles in a ring originate from vascular meristems with delayed differentiation. Accessory bundles in the wings of the petiole seem to originate as a result of fusion of two separate strands. The vascular cambium with its characteristic radial alignment of cells is present in between xylem and phloem in the leaf and the petiole.
pp 18-23 January 1968
Tuber extract of nutgrass, when applied to the growing medium, inhibited the germination and growth of 10 crop species under the laboratory conditions. On the basis of above findings, the presence of some phytotoxic substance(s), however, in nutgrass tubers has been confirmed. Although the germination and growth of all the crops, included in this experiment, was inhibited by the phytotoxins present in nutgrass tubers yet the degree of such inhibition varied with different crop species.
pp 24-30 January 1968
The paper reports the occurrence of twelve species of Archiannelids in the interstitial sands of the Waltair beach. Of these, six European species are reported for the first time from Indian waters and their occurrence on the Indian coast is of great interest from a Zoogeographical aspect of their distribution.
pp 31-34 January 1968