COMPEHIBHIIM. XXIII 



Tribe II. A^pidteae. Sori roundish or oblong. Indusimn 

 saperior, reniform, round or oblong, if reniform attached 

 at the top of a more or less deep sinus, if round pel- 

 tate, if oblong attached by its longitudinal axis, all 

 opening all round the edge or nearly so. 



GENUS 15. OLEANDRA. Indusium reniform. Fronds 

 simple, articulate to the rhizome; veins free. 



GENUS 16. AIITHROPTERIS. Indusium reniform. 

 Fronds pinnate, articulate to the rhizome; pinnae 

 articulate to the rachis ; veins free. 



GENUS 17. NEPHROLEPIS. Like genus 16, but the 

 fronds not articulate to the rhizome. 



GENUS 18. CYCLOPELTIS. Like genus 17, but the 

 indusium round. 



GENUS 19. POLYSTICHUM. Indusium round or re- 

 niform. Fronds divided, not articulate to the rhi- 

 zome. Leaflets subrhomboidal, not articulate to 

 the rachis ; upper base broadly, lower narrovrly 

 cuneate; veins, free. 



GENUS 20. DIDYMOGHLAENA. Like genus 19, but 

 the indusium oblong. Leaflets deciduous. 



GENUS 21. PLEOCNEMIA. Indusium reniform, rarely 

 round. Fronds divided, not articulate to the rhizome ; 

 veins anastomosing in costal and costular arches. 



GENUS 22. DRYOPTERIS. Indusium reniform, rarely 

 round. Fronds divided, not articulate to the rhi- 

 zome; veins free, but then the leaflets not as in 

 genus 19, or the lower veins anastomosing and 

 forming costal rows of regular, ± deltoid areolae. 



GENUS 25. MESOCHLAENA. Like genus 22, but the 

 veins not freei Indusium oblong. 



