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The development of the embryo is studied in two species of Buddleja: B stachyoides Chem. et Schldl. and B tubiflora Benth. The main conclusions are: Embryogeny follows the Veronica variation of the Onagrad type. According with the Souèges System, the mode of development may be designated as belonging to the First Grand Division, Serie A, Megarchtype IV. This pattern is present in most of the Scrophulariaceae representatives The hypothesis suggesting close affinities between Buddleja and some genera of Scrophulariaceae seems to be strengthened once more by the peculiarities of their embryogeny. [ABSTRACT FROM AUTHOR]

This paper deals with the endosperm and episperm development of two species of Buddleja: B. stachyoides Chain. et Schldl. and B. tubiflora Benth. The following are the main conclusions: --The cellular development of the endosperm is --according to the EODP system (Di Fulvio, 1983; 1985)-- of the heteropolar type and longitudinal subtype (EODP 1221) with chalazal and micropylar primary haustoria. The cells near the primary haustoria differentiate, secondarily, as haustorial cells. --In the mature seed the endosperm is ruminate and corresponds to the Verbascum type of Periasamy. --The endothelium is differentiated at the time of the anthesis but its cells divide actively after fertilization only by means of anticlinal divisions; in this way, the number of cells around the endosperm remains constant since the anthesis until the seed development is completed. These cells keep pace with the endosperm expansion becoming considerably enlarged. --The episperm consists of only 2 layers, the endothelium and the outer epidermis. The outer epidermal cells develop U-like secondary lignified thickenings along the radial and inner tangential walls; the outer tangential wall is compressed. Cells with reticulated thickenings develop around the micropyle. --Preliminary phytochemical and morphological studies showed close affinities between Buddleja and some genera of the Scrophulariaceae. The present study emphasizes this relationship and suggests that Buddlejaceae should be considered as an independent family, to included in the order Scrophulariales. Moreover, the absence of embryological similarities with Loganiaceae is at the same time demonstrated. [ABSTRACT FROM AUTHOR]