. Elementary botany . Fig. 172. Archegonium of riccia, showing neck, venter, and the egg; archegonium is partly- surrounded by the tissue of the thallus. (Riccia crystallina.) Fig. 173- Young embryo (sporogoni- um) of riccia, within the venter of the archegonium ; the latter has now two layers of cells. (Riccia The egg, on the other hand, after acquiring a thin wall, swells up and fills the cavity of the venter. Then it divides by a cross wall into two cells. These two grow, and divide again, and so on until there is formed a quite large mass of cells rounded in form and still co
. Elementary botany . Fig. 172. Archegonium of riccia, showing neck, venter, and the egg; archegonium is partly- surrounded by the tissue of the thallus. (Riccia crystallina.) Fig. 173- Young embryo (sporogoni- um) of riccia, within the venter of the archegonium ; the latter has now two layers of cells. (Riccia The egg, on the other hand, after acquiring a thin wall, swells up and fills the cavity of the venter. Then it divides by a cross wall into two cells. These two grow, and divide again, and so on until there is formed a quite large mass of cells rounded in form and still contained in the venter of the archegonium, which itself increases in size by the growth of the cells of the wall. 313. Sporogonium of riccia.—The fruit of riccia, which is developed from the fertilized egg in the archegonium, forms a rounded capsule still enclosed in the venter of the archegonium, which grows also to provide space for it. Therefore a section through the plant at this time, as described for the study of the archegonium, should show this capsule. The capsule then is a rounded mass of cells developed from the egg. A sin- gle outer layer of cells forms the wall, and therefore is sterile.
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Keywords: ., bookcentury1800, bookdecade1890, bookpublisher, booksubjectbotany
