. The Eusporangiatae; the comparative morphology of the Ophioglossaceae and Marattiaceae. Ophioglossaceae; Marattiaceae. THE OLDER SPOROPHYTE 185 The young sporophyte of Kaulfussia is almost completely destitute of the tannin cells which are so conspicuous a feature in Dancea, and these tannin cells are prac- tically entirely absent from the sporophyte throughout its whole existence. In this respect there is a marked resemblance to Ophioglossum. The mucilage ducts are also somewhat less developed than in the other Marattiacese and are mainly con- fined to the central part of the stem in proxim
. The Eusporangiatae; the comparative morphology of the Ophioglossaceae and Marattiaceae. Ophioglossaceae; Marattiaceae. THE OLDER SPOROPHYTE 185 The young sporophyte of Kaulfussia is almost completely destitute of the tannin cells which are so conspicuous a feature in Dancea, and these tannin cells are prac- tically entirely absent from the sporophyte throughout its whole existence. In this respect there is a marked resemblance to Ophioglossum. The mucilage ducts are also somewhat less developed than in the other Marattiacese and are mainly con- fined to the central part of the stem in proximity to the vascular bundles. At a late period they may also appear in the cortical region. Their lysigenous origin is less evident than in Dancea and it is not impossible that they may sometimes be of schizogenous origin, as Brebner states is often the case in Dancea. The structure of the vascular strands is very much like that of Dancea, as a reference to the figures will show. There are developed slender, spirally-marked protoxylem elements like those in Dancea and which we have already seen occur also among the Ophioglossaceae, in Helmtnthostachys. The stipules in the young plants o( Kaulfussia are much less definite than they are in Dancea. A cross-section through the bases of the young leaves shows that instead of the bases appearing free, each with its distinct stipules, the leaf is confluent with the next one, one side being slightly extended and free. The leaf base thus incloses the next younger leaf completely on one side, but leaves it free on the. Fig. 169. A. Bundle from intermediate region of a very young sporophyte of Kaulfussia. X150. B. Section of primary root. X150. C. Section of bundle of second root, en, endodermis. X150. Other (fig. 168, 5). In the later leaves the stipules become more conspicuous, but they are always connected by a very conspicuous commissure in front (fig. 171, coni) so that a section of the young leaf base shows a space between the front
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