Organography of plants, especially of the archegoniatae and spermaphyta . e of it thereis the shoot. Whilstusually the whole lat-eral segment of theapical cell is claimedfor the formation ofthe leaf, occasionallya few of the cellsbeing devoted to theconstruction of a freestem-surface, here inthe case of the branch-ing the ventral portionof the segment is de-voted to the makingof a branch, and theupper part of it onlyis left for the leafDifferent in degreeonly is the layingdown of the primor-dium of the branch in the basiscopic basilar portion of the segment, that isto say, the formation of the
Organography of plants, especially of the archegoniatae and spermaphyta . e of it thereis the shoot. Whilstusually the whole lat-eral segment of theapical cell is claimedfor the formation ofthe leaf, occasionallya few of the cellsbeing devoted to theconstruction of a freestem-surface, here inthe case of the branch-ing the ventral portionof the segment is de-voted to the makingof a branch, and theupper part of it onlyis left for the leafDifferent in degreeonly is the layingdown of the primor-dium of the branch in the basiscopic basilar portion of the segment, that isto say, the formation of the leaf out of the segment is complete, but onecell on the under basiscopic portion of the segment becomes the apicalcell of the primordium of a branch, and when this develops we find,as in Radula compianata, the branch underneath a completely developedleaf. Resting buds. The lateral shoots of many species may become restingbuds. In Lejeunia, for example, the first three leaves of the lateral shootcoalesce to form an envelope surrounding the primordium of the shoot which. Fig. 40. Bryopteris Clicina. Habit. Tlie shoot branches in one plane. Atthe base are stolons with reduced leaves which can give rise to new shoot-systems and at the same time help in anchoring the plant. Magnified 4. RHIZOIDS 45 rests for an indefinite period. In the further development of the bud theenvelope is broken through. Endogenetic shoots. This leads us to what Leitgeb has described asthe endogenetic origin of the ventral and lateral shoots of many says that the flagella of Mastigobryum arc formed from cells lyingimmediately under the outer cells, and the same is the case with the fructi-fication-branches of this plant, as well as of Lepidozia. Calypogeia, andothers. The disposition of these endogenetic branches in Lophocoleabidentata and in Jungermannia bicuspidata is peculiar. They are almostexclusively ventral, and the branches spread themselves out upon the sub-stratum to both sides of the
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