The Concept of Perispore—An Assessment

Abstract

The TEhI observations of the perispore reveal: (I) The presence of the perispore in many families tvhich were earlier considered non-perinate. However. this perispore differs in nature from the Lhl-detected layer. (2) The conventional perispore is double layered with septa running in between the two, and may be acetolysis-resistant, acetolysis-affected or acetolysis-soluble. (3) The so-called loose perispore in Aspleniaceae and Aspidiaceae is the only Lhl-visible layer which gives the false impression of being loose. (4) It is fibrillar in nature, although it differs in certain genera. Although extra exosporial in nature, it is doubtful whether the equatorial collar in Preris-group of ferns, the elaters in Eqrriserrrrti and the proximal cuplike structures of the spore coat in Gleicheniaceae, have a distinct position in the line of evolution of perispore. Also, it is not yet definite whether the genetic control regarding the patterning of the perispore is passed through the apertural "fissures" in the developing exine.

Observations on indusia in Adiantum L. (Pteridaceae : Vittarioideae) of North-East India

“…plays a significant role in their systematics. It serves as a reliable source of unit to circumscribe specificity or to establish hypothetical relationships between or among species within a genus (Devi 1980;Das & Dixit 2001). In the present paper, the morphology of indusia in eight (8) species of maiden ferns (A. capillus-veneris L., A. caudatum L., A. edgeworthii Hook., A. flabellulatum L., A. incisum Forssk., A. peruvianum Klotzsch, A. philippense L., A. raddianum C. Presl) found in North-East India is critically studied.…”

Spore studies in the genus Gymnocarpium

“…The perispores were often much more elaborate and irregularly crested than usual. Devi (1980) has reported seeing several cases of highly developed perisporal matter over shrunken or sterile spores, especially in Polystichum and Dryopteris.…”

Chemical constituents of Cyrtomium fortumei (J.) Smith

“…Smith is a popular traditional medicine plant belonging to the Dryopteridaceae family, which comprises approximately 14 genera and 1700 species throughout the world (Dev 1980;Dai et al 2010). In the past, extracts from rhizomes of the plant were usually used as vermifuges for humans (Socolsky et al 2010).…”