105 157 



Subgenus 5. Glaphyropteris (Presi) c. Chr. 

 Biolog. Arbejder tilegnede Eug. Warming p. 80. 1911. 



Glaphyropteris Presl, Abhandl. böhm. Ges. Wiss. V. 5: 344, 1848. 



A small subgenus ot mostly large species with a bipinnatifid lamina and an 

 often very large (1 cm or more long), acute aërophore at the bases of the pinnæ 

 beneath and similar but smaller aërophores at the bases of the midribs 

 of the segments (not found in D. mapiriensis) ^• 



Segments close, rectangular with broad, bluntly rounded apex and entire 

 margins, rarely the apex is acute. Veins very close and numerous, simple, the 

 basal ones reaching the margins above sinus. Pubescence somewhat variable (see 

 below), the under-surface of most species covered with numerous, sessile, red 

 glands, which are deciduous and therefore not found in older specimens. 



By these characters the six species referred to Glaphyropteris differ from 

 Lastrea, but I fear that the characters mentioned are not sufficient for the segre- 

 gration of the two proposed subgenera. If one should prefer to treat Lastrea as a 

 genus, which would be a very natural treatment, Glaphyropteris ought to be referred 

 to it as a subgenus. It is true that the typical species of Glaphyropteris, D. decus- 

 sata, is very different from all species referred to Lastrea, but it is no doubt 

 intimately related to the three first species mentioned below. These three species 

 show both the characters of Lastrea and Glaphyropteris besides some others peculiar 

 to them alone ; with the same right they could be referred to Lastrea, to a proper 

 subgenus or to Glaphyropteris. I prefer here to refer them to a proper section of 

 Glaphyropteris, which they are perhaps nearest related to. The subgenus thus is 

 divided into two groups each including three species: 



1. Group of D. Thomsonii. The three species belonging here resemble species 

 of Lastrea, especially those related to D. radis, by the shape of the lamina, which 

 is abruptly narrowed downwards with 3—4 pairs of glanduliform warts along the 

 stipe, and further by the shortly and antrorselj' setose costæ above; the veins are 

 not so close as in the species af Glaphyropteris proper, which they resemble by 

 the presence of aërophores at the base of the midribs beneath. 



The pubescence of the costæ beneath (partly also of the rachis) is peculiar 

 and different from all species of Lastrea and Eu-Glaphyropteris. The costæ be- 

 neath are, namely, shortly and often densely cinereo-tonientose by sessile, 2 — 3- 

 b ranched hairs, which do not resemble the stalked, branched hairs of Goniop- 

 teris. Further the sori seem to be indusiate at least in D. Cahadasii and D. 

 macradenia. The three species belonging here were in my former papers referred 

 to the group of D. opposita. ("Revision" nr. 67, 68 and 79). 



' The most important function of the aërophores or better "pneumatophores" appears to be 

 during the development of the leaf, while the growing parts of this are covered by mucilage. Very 

 likely they are provisions for the aeration of the young parts; in the developed leaf they are shriveled. 

 See Bower, Annals of Botany -24: 427—428, foot-note, 1910. 



D. K. D. Vidensk. SeUk. Skr.. 7. Hække, naturvldensk. og mathem. Afd. X. 2. 21 



