With 7 figures in the text)In his classical work on the embryology of the Leguminosae, Guignard (1882) included an account of the more important features in the development of the embryo in a few species belonging to the Phaseoleae. He found a considerable variation in the organization of the suspensor, some species showing a rudimentary suspensor of a few superposed cells and others showing a massive suspensor. Since then, several investigators have worked on Phaseolus, but the other genera of the tribe have attracted very little attention. During an embryological study of Vigna Catjang (Indian cowpea), a sub-erect annual cultivated for its edible pods, certain interesting features were observed in the nutritional mechanism of the developing seed and they are described in this paper. The material was fixed in Navaschin's fiuid, and the sections were stained in Heidenhain's iron-alum haematoxylin.The ovules are found in a single row on the marginal placenta. There is a short funiculus and two integuments, of which the outer forms the micropyle. At the time of fertilization the ovule shows the four-or five-layered outer integument which is more massive in the micropylar region, the two-layered inner integument ending just behind the apex of the nucellus, and the two or three layers of nucellar cells at the sides (the nucellus is crushed towards the top of the embryo sac). When the fertilized egg starts dividing to form the embryo, the ovule enlarges considerably, and striking changes take place in cells of the nucellus and integument. The cells of the inner layer of the nucellus become transversely stretched and give the appearance of a tapetum. As this layer is disorganized by the growing embryo sac, the remaining layer of the nucellus shows a similar organization, and when the whole of the nucellus is consumed the inner layer of the inner integument assumes the tapetal appearance (Fig. i). As the enlargement of the embryo sac is more rapid in the micropylar half, even the inner integument is crushed at certain points in this region, although in the lower half of the ovule the nucellar layers are still visible. At this stage very prominent meristematic zones can be seen around the embryo sac, particularly in the micropylar region of the outer integument and in the chalaza (Fig. 2). Meristematic activity is also seen along the sides of the embryo sac in the cells of the outer integument. The inner integument, however, shows only the tapetum-like inner layer and a crushed outer layer. In the embryonal region both layers of the inner integument are almost crushed.With the further expansion of the embryo sac, even the tapetum-like layer of the inner integument gets crushed and disorganized. The endosperm which was so far free nuclear forms a single layer of cells in the micropylar part which present the same tapetal organization (Fig. 3). The embryo which is in an advanced stage of development shows a well-
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