Post-graduate and Research Department of Zoology, Loyola College, Chennai-600 034, Tamil Nadu (India).
The reaction of egg cuticle of Diplonychus indicus Venk. & Rao to various fixatives, viz, 5% H2SO4, 5% HCI, ethanol, formaline, acetone, picric acid, acetic acid, Bouin's fluid, butanol, chloroform, 70% alcohol, ether, 5% HNO4 and methanol was observed to record the colour change, it's intensity and time taken for the darkening process. The entire egg, egg chorion and content of both large and small sized eggs were subjected to acid hydrolysis. The darkening of the egg chorion directly influenced the amino acid fractions of the chorion. In small sized eggs, higher fractions of amino acids were seen when compared with large sized eggs. After treating the eggs with chloroform as a fixative, certain amino acids, viz, norleucine, isoleucine, tryptamine and hydroxyproline were lost. Chorion showed vast variation in bound amino acids than the whole egg and egg content. Since the fixatives, viz, formaline and Bouin's fluid didn't cause any colour change on the egg cuticle, these are the best fixatives to preserve the eggs.
