272 SUMMARY OF CURRENT RESEARCHES RELATING TO 



only one genus, while many of the most important reactions give no 

 result, so that the numerous assertions as to relationships have no 

 scientific value. Especially are we doubtful of such results as the 

 relationship of the Pinaceae to the Magnoliaceae on the one hand and to 

 the Selaginaceae on the other. Further investigation of this character 

 may be awaited with interest, but their results will have more value if 

 attention is confined to small groups of nearly related species and to 

 well-defined reactions. 



CRYPTOGAMS. 



Pteridophyta- 

 (By A. Gepp, M.A. F.L.S.) 



Structure and Affinities of Macroglossum AlidsB.*— D. H. Campbell 

 discusses the structure and affinities of Macroglossum Copeland (1909), 

 a fern of new generic type. His summary states that : — 1. The genus 

 contains two species, M. Alidse, found in Sarawak, Borneo, and M. 

 Smithii, growing in Buitenzorg Botanic Garden, but of unknown 

 origin. 2. AYhen mature, M. Alidse is as large as Angiopteris, with 

 leaves 4 m. long, but differs in habit, with its numerous, upright, 

 simply pinnate fronds, and in its elongate, partly immersed, sori. 

 3. The gametophyte is much as in Angiopteris. 4. The antheridia 

 are both dorsal and ventral, with more numerous sperm-cells and small 

 spermatozoids. 5. The archegonia are as va. Angiopteris. 6. The embryo 

 has a conspicuous suspensor, as in Dansea. 7. The development of the 

 embryo is as in other Marattiaceae. The apical cell is not always 

 evident. 8. The young sporophyte has no true cauline stele, but leaf- 

 traces only. 9. The structure of the axis is intermediate between 

 Dansea and Angiopteris. 10. The cotyledon is as in Angiopteris ; the 

 first leaves, about ten, remain simple. Stipules first appear in the third 

 leaf. The first leaf-trace shows a collateral structure. 11. The primary 

 root is usually diarch, and has a single initial cell. A single root is 

 formed for each of the early leaves. 12. The leaf of the adult sporophyte 

 is simply pinnate, and the anatomy of the leaflets is different from that 

 in Angiopteris. There is a conspicuous mucilage duct below the sorus, 

 and a better developed palisade tissue. 13. The sporangia of Macro- 

 glossum, especially M. Alidse, are smaller than those of Angiopteris, and 

 very much more numerous. The sorus is more compact, and partially 

 sunk in a trough formed by elevated ridges between the sori, while in 

 Angiopteris no such ridges are present. The annulus is very slightly 

 developed in Macroglossum, and the indusial hairs very much more 

 conspicuous than in Angiopteris. 14. The roots of the adult plant have 

 no mucilage ducts, thus differing from the other Marattiaceae. 15. 

 Macroglossum should undoubtedly be placed in the Angiopterideaa, but 

 its affinities are with Archangiopteris rather than with Angiopteris. 

 31. Alidse is farther removed than M. Smithii from Angiopteris. 



* Anu. Bot., xxviii. (1914) pp. G51-69 (3 pis. and figs.). 



