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Pal, Sunanda and I'd, N. (Dept. Dot., Government College, Darjeeling, West Bengal, India.) Spore ttiorphology arid foxoriortiy of Polypodiaceae. Grana 10: 141-148, illus., 1970.-The examination of spores belonging to eight species reprcscnting five genera of Polypodiaceae reveals that they are typically free, anisopolar and monolete (bilateral). In a majority of cases the sporcs are yellow and have a short Iaesura-about half the length of the greater equatorial axis of the spore. Generally, the spores arc elliptical in polar view and plano-convex to concavoconvex in profile view but in cross section they vaxy in shape. The average measurements in equatorial plane range from 44 p to 71 11 whereas in the polar direction they vary from 27 11 t o 47 p . The cxine is thin (about 2.5 p) and nearly smooth (Iaevigosc-scabrous-foveolose) in MicroJoriirtii and Phyttiarodes but in the other investigated genera, it is thicker, possessing different types of projections. P: E varies from 4.6 to 5.5 : 8. Oil globules are present in the spores of some species.Available data o n morphology of spores of Polypodiaceae have been tabulated in two tables o n a comparative basis and their importance in taxonomy and phylogeny of some genera have been discussed. INTRODUCTIONA critical study of the spores of fcrns and recognition of their charactcristics in considcring phylogcny and classification has reccived little attention in the past. Until rcccnt decades, the spores of ferns wcre not adcquatcly cxamincd and only a fcw gcncralised terms wcre in use 'for describing their morphology. The importance of the morphology of fcrn spores has been rccognised by Copcland (1947) and has also rcccived proper considcration by Selling India is wcll rcprcscntcd by gcncra and species of Polypodiaceae (sensir stricto) and obscrvations have already been made on a number of genera by Nayar and his co-workers and a few others. The present work was undertaken to makc a comparntivc study on sporcs of some mcmbcrs of the family and incorporatcs eight spccics (including one Burmese spccics) representing fivc (including one American) genera. MATERIALS AND METHODSSpores of the following spccics wcrc studicd: Phpirintodes scolopeirdrici (Burm.) Ching (Fig. 1). (Figs. 3 a and b).Microsoriiirti piittctatiiiir: laesura short-over half the length of greater equatorial axis, fccbly rimmed, outline of spore-elliptical in polar view, plano-convex in profile and nearly circular in cross scction; P : E = 5.5 : 8 ; cxinc thin-about 2.5 p, laevigose; size-equatorial 36(44)56 11, polar 25(30)35 p (Fig. 4).M. nirrsijoliritri: laesura vcry short-less than half the length of greater equatorial axis, not rimmed; outline of spore-clliptical in polar view, concavo-convex in profilc and proximally V- Crypsiniis grijjithianrrs: laesura vcry shortSpore ttiorphology of Polypodiaceae 143 diversity in many aspects. In the light of the points raised in the previous paragraph, a critical reinvestigation is warranted for most of these genera. In this connection, a reference ma...

A selective electrode for oxygen reduction reaction (ORR) and electrocatalytic reduction of 4-nitrophenol (p-NP) was fabricated on a glassy carbon electrode using organic−inorganic Bi 2 MoO 6 /H 2 TPP nanocomposites with different weight percentages of tetraphenylporphyrin, synthesized by the solvothermal process. Materials thus synthesized were characterized through UV−Vis diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDX), highresolution transmission electron microscopy (HR-TEM), Fourier transform infrared spectroscopy (FT-IR), and X-ray diffraction (XRD) analysis. The electrocatalytic performance of the modified electrode toward ORR in the 0.1 M KOH solution, the onset potential E onset (0.942 V), E 1/2 (0.704 V) vs RHE, J d (−5.545 mA cm −2 ), and n = 4 physicochemical parameters were well appreciable. It exhibits good catalytic activity toward ORR through a fourelectron pathway with excellent stability and high active site density, and thus, the in situ Porphy-decorated metal oxide system facilitates the electron transport process. High selectivity and efficacy for the oxygen reduction reaction (ORR) are a significant measure for several energy-converting applications. The decorated electrode, glassy carbon electrode (GCE)/Bi 2 MoO 6 /3 wt % Porphy, serves as an electrochemical sensor that exhibited good sensitivity (0.4683 μAμM −1 cm −2 ), good reproducibility, a low detection limit (0.0940 μM), and long-term stability in the aqueous phase without any appreciable effect in the presence of some common organic and inorganic interferences for the detection of p-NP in a linear concentration range of 0.5−350 μM. Therefore, the material performs as an effective electrode for both the ORR and the electrocatalytic reduction of p-NP with real matrix samples at room conditions.

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