Organography of plants, especially of the archegoniatae and spermaphyta . espond in essen-tials with the sac of Calypogeia, but with its archegonial foot, w^hich is onlydeveloped after fertilization, and into which the sporogonium penetrates. My investigations have led me to a different result from that reached by Stephani, HepaticaeAustraliae, in Hedwigia, xxviii ^iSSg), p. 276, who says the basal portion of the calyptra is soon con-crescent with the wall of the sac, and as this elongates progressively the calyptra grows out into along tube at whose base the sporogonium sits. This description
Organography of plants, especially of the archegoniatae and spermaphyta . espond in essen-tials with the sac of Calypogeia, but with its archegonial foot, w^hich is onlydeveloped after fertilization, and into which the sporogonium penetrates. My investigations have led me to a different result from that reached by Stephani, HepaticaeAustraliae, in Hedwigia, xxviii ^iSSg), p. 276, who says the basal portion of the calyptra is soon con-crescent with the wall of the sac, and as this elongates progressively the calyptra grows out into along tube at whose base the sporogonium sits. This description proceeds from the assumption that thedevelopment is originally like that in Calypogeia, and that there is formed an actual sac with which thecalyptra is united. Such a concrescence does not take place, and the process is much more like thatobserved in the penetration of the embryo of Blyttia and others into the tissue lying below them. [Ihave, since the above was written, seen living specimens in New Zealand, and convinced myself thatthe sac never touches the ground.]. plantsac Fig. 80. Gymnanthe saccatabearing a sac Magnified 2. Ilongitudinal section ; the embryo indicateiiby dots. Ill, the shallow pit upon the of the sac in which the archegoniastand ; seen in transverse section. DISPOSITION OF SEXUAL ORGANS 93 A further obscure notion which is found in the literature of Hepaticae concernsthese geocalycean Jungermannieae, that of the involucel. This is said to bea special second envelope which is developed within the calyptra; but so far asI see it is only a collar-like outgrowth upon the suctorial swollen base of the sporo-gonium. To speak of an involucel seems to me superfluous. A similar collar isfound, as Gottsche has shown, in Pellia epiphylla and elsewhere. We have hereonly a surface increase of the haustorium in connexion with the peculiar con-figuration of the sac, not an envelope. 3. now we review the relationships which I have depicted, we see
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