Organography of plants, especially of the archegoniatae and spermaphyta . hese landmarks are developed. This also takes place in Marchantia, but in a less pronounced manner. ^ These gemma-sjales require investigation especiallj- in their biological relationships. A similardimorphism of gemmae appears probably in the genus Tetraphis amongst the Musci. GOEB12L II r- 50 ASEXUAL PROPAGATION OF HEPATICAE A description of the formation of the gemmae in the several forms ofHepaticae Vvould have no general interest. Their appearance is sporadicwithin cycles of affinity, and even within genera. Anthoce
Organography of plants, especially of the archegoniatae and spermaphyta . hese landmarks are developed. This also takes place in Marchantia, but in a less pronounced manner. ^ These gemma-sjales require investigation especiallj- in their biological relationships. A similardimorphism of gemmae appears probably in the genus Tetraphis amongst the Musci. GOEB12L II r- 50 ASEXUAL PROPAGATION OF HEPATICAE A description of the formation of the gemmae in the several forms ofHepaticae Vvould have no general interest. Their appearance is sporadicwithin cycles of affinity, and even within genera. Anthoceros glandulosus,for example, is the only known species of the genus in which they are in it they take the form of oval cell-masses. Amongst the Marchantieae,Marchantia and Lunularia alone possess them, and how profusely they aredistributed in these genera is well known to gardeners. They overrun everypot in cultivation. The occurrence of gemmae produced from shoots is not unknown in thefoliose Jungermannieae, and they may be either unicellular or before their. Fig. 45. Lejeunia. Formation of jremmae. 1, Lejeunia (Odontolejeunia) mirabilis, Stepli. Gemma; .S, apicalcell; A, point of attachment. Rhizoids in the form of long tubes have developed upon the under side from singlemarginal cells. 11, ill, Lejeunia (Cololejeunia) Goebelii. 11, portion of a leaf with three gemmae still attached ;J, .y, indicate the points of attachment of two gemmae which have fallen off. ill, gemma with four anchoring-organs, j, and two apical cells. separation grow into cell-masses. The formation of gemmae occurs in manyspecies, usually upon the edge or upon the tip of leaves, and the gemmaeappear then often as long branched yeast-like chains. The several gemma-cells separate easily from one another in moisture. In Lophocolea bidentataaggregates of cells loosely joined together fall from the leaves. According asthe formation of gemmae takes place at an early or late stage, the formationof the
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