Volume 90, Issue 3
May 1981, pages 281-363
pp 281-289 May 1981
The systematics ofNybelinia sp. is briefly presented. The percentage incidence and intensity of infection are seen to be high during colder months, and in the smallest and the largest fish. Both sexes are more or less equally susceptible to the infection. The histopathological change in the infected tissue is in the form of a fibrous connective tissue reaction to encapsulate the parasite. A curious mechanism seems to be involved in the formation of ‘Nybelinia cysts’ on the outer wall of the oesophagus. This aspect is discussed in detail.
pp 291-294 May 1981
The copper and protein contents have been determined in the blood and also in the purified haemocyanin of the freshwater field crab,Oziotelphusa senex senex (Fabricius) in relation to sex. The haemocyanin content was fairly higher in the blood of female crabs when compared to the males. However, the copper-protein ratio in the purified haemocyanin of both male and female crabs is 0·167%. Based on the copper content, the minimal molecular weight of the functional unit of theO. senex senex haemocyanin has been calculated as 76,120 daltons. The sex-based difference in the haemocyanin concentration has been discussed in the light of the existing literature.
pp 295-301 May 1981
Some changes in the haematologicaJ values of the fishHeteropneustes fossilis which were infected with trypanosomes are presented. The presence of trypanosomes in the blood caused conspicuous changes in TEC, TLC, Hb, MCH and DLC values, correlated with the intensity of infection. In general anaemia accompanied with erythropenia, microcytosis, macrocytosis, basophilia or polychromasia, vacuolization of blood cells was noted. The TLC value showed interesting and contrasting results.
pp 303-306 May 1981
The regulation of blood pH during long-term swimming in mullet,Rhinomugil corsula (Hamilton) acclimated to 30° C and forced to swim in a tunnel type apparatus for five hours continuoustly was studied. The accumulation of lactic acid in muscle caused a reduction of muscle pH. But in blood the reduction of pH during the 1st hour of exercise was followed by the recovery of pH to norma level during the later hours of exercise. The maintenance of pH was apparently caused by the retention of CO2 in the form of HCO3 ions in blood.
pp 307-314 May 1981
The histology and histochemistry of the digestive gland and the investing epidermis ofPila virens are described. The digestive gland tubule epithelium is made up of the digestive cells and calcium-cum-excretory cells. The digestive cells are columnar, vacuolated cells and carry out the function of secretion and absorption. The calcium-cum-excretory cells are pyramidal non-vacuolated cells that harbour prominent excretory pellets. These cells serve as reservoirs of calcium and also carry out the function of excretion. The investing epidermis of the gland is composed of low cuboidal epidermal cells interspersed with mucous cells that seem to secrete both neutral and acid mucosubstances. Overlying this is a melanin layer.
pp 315-320 May 1981
The morphology and life history of a cephaline gregarineHirmocystis lepropi n. sp. from the gut of the beetle,Lepropus sp. are described. The parasite passes through an intracellular phase of development before reaching the trophozoite stage. The trophozoite has a length of 77·5 to 580·0μ, and has an epimerite, a protomerite and a deutomerite in its body. The gametocysts are ovoidal bodies and give rise to spores. Each spore measures 6·0×4·0μ.
pp 321-331 May 1981
Homogeneity and diversity of the intertidal polychaetes in the Vasishta Godavari estuary are discussed basing on the collections made at six fixed stations during October 1976 and January 1978. Matrix and rarefaction methods are adopted for arriving at homogeneity and diversity respectively. Homogeneity varied along with the salinity structure in the estuary; high percentage of affinity was observed during the recovery and summer periods while affinity was relatively low during annual freshwater flood period. The factors generally controlling the diversity and the reasons for high polychaete diversity in this estuary are discussed.
pp 333-336 May 1981
Redescription ofRaillietina (Raillietina) kordofanensis, Meggitt and Subramanian (1927) from a new host, viz.,Columba livia domestica is made. The specimens closely resemble the species described by Meggitt and Subramanian (1927) except in having a longer cirrus pouch and smaller rostellar hooks. The teratological aberrations, viz., the presence of two cirrus pouches in the same proglottid with internal seminal vesicle are also reported. Taxonometry in biostatistical terms reveal the closeness of two species.
pp 337-341 May 1981
The analytic potential of arginase has been studied in the liver and kidney of frogRana hexadactyla during prolonged starvation. Starvation involves the alterations of Michaelis-Menten constant and the maximal velocity of arginase in both the tissues. Increased activation energy values for the enzymes of both the tissues during starvation indicated decreased catalytic potential.
pp 343-349 May 1981
A new approach for differentiating between different groups of individuals on the basis of statistical evaluation of pairs of attributes (each member belonging to different group) is proposed. The “polythetic divisive ” classificatory method is employed. The methods discussed may prove helpful in establishing precise interspecific variations as also the variability amongst various higher taxa in cestode taxonomy thus contributing a support in the direction of revision attempts of future workers.
pp 351-355 May 1981
Presence of orbicular muscle mark close to hinge margin and typical exogyriid ligamental area characterised by twisted nature, indistinct anterior bourrelet and sharp-crested posterior bourrelet as revealed in our recently acquired material confirms placement of the genusVultogryphaea Vyalov to subfamily Exogyrinae as proposed by Stenzel. New speciesVultogryphaea erumanurensis comes from Erumanur, Vriddachalam area, Tamil Nadu. The present material takes the time range of the genus to Maestrichtian.
pp 357-363 May 1981
The seasonal variations in the various categories of lipids have been investigated by dividing the year into five seasons, i.e. spring, summer, rains, autumn and winter. The data have been analysed by using student’st-test. Non-significant seasonal variations (p<0.05) are found when all the seasons are compared for total lipids, non-polar lipids, glycerides and unidentified lipids and the ratio of phospholipids and non-polar lipids. All the various lipid components and their ratios vary non-significantiy (p<0.05) in summer vs autumn, summer vs winter and autumn vs winter. Some lipid components vary significantly at different levels when seasons are compared. The significance of the results has been discussed.