Evaluation and information of seed structure for systematics and phylogenetic considerations of angiosperm plants are reflected in a number of compiling monographs (Netolitzky, 1926; Corner, 1976; “Comparative anatomy of seeds”, 1985-1999). However, publications devoted comparative seed anatomy of gymnosperms are a few (Chamberlain, 1935; Schnarf, 1937). Morphology and anatomy of developing and mature seeds and ultrastructure of seed coats of gymnosperms (124 species from 51 genera from 16 families) were studied during 1984-1998. During these long-term investigations it is established: 1) main evolutionary structural types of gymnosperm seeds; 2) peculiarities of histogenesis of seed coats in relation to their origin in different gymnosperm taxa; 3) classification of systematic evaluating characters of seed structure on species, genus, family, class levels, using complex analysis; 4) revision different systems of gymnosperms and 5) new phylogenetic scheme of gymnosperms. Obtained data are published in two monographs in Russia (Tarbaeva, 1995; 1997), but the phylogenetic scheme isn’t yet published.

Key words: evolution, gymnosperms, seed structure, systematics, ultrastructure