A well‐known result of Ehrenfeucht states that a difference polynomial f(X)‐g(Y) in two variables X, Y with complex coefficients is irreducible if the degrees of f and g are coprime. Panaitopol and Stefǎnescu generalized this result, by giving an irreducibility condition for a larger class of polynomials called “generalized difference polynomials”. This paper gives an irreducibility criterion for more general polynomials, of which the criterion of Panaitopol and Stefǎnescu is a special case.

Two charophytes-Platychara perlala (Peck & Reker) Grambast and Nemegtichara grambosti sp. nov- are described and illustrated from the Deccan Intertrappean beds near Rangapur, district Rangareddi, Andhra Pradesh. The genus Nemegtichara Karczewska & Ziembinska-Tworzydlo, first described from the Palaeogene "White Beds" of the Nemegt Basin in Mongolia and also known from the Cretaceous- Middle Eocene of China is being recorded for the first time from India. The age and palaeobiogeographic implications of the assemblage are also discussed.

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