The Genus Dicroidium from the Triassic of Nidpur, Madhya Pradesh, India

Abstract

Three new species of Dicroidium are desc1'ibed here from the Triassic of Nidpur, Sidhi District, Madhya Pradesh. Externally these three species are very similar to each other except that in D. nidpurensis and D. papillosum the venation is odontopteroid type, whereas, in D. gopadensis it is alethopteroid type. In the cuticular structure these species differ from each other main Iv in the presence or absence of papillae. In D. nidpurensis cell surface is smooth but in D. papillosum and D. gopadensis surface wall is usually papillate. In D. papillosum, subsidiary cells may be unspecialized or papillate, whereas, in D. gopadensis they are usually papillate.