196 FERNS : BRITISH AND FOREIGN. 



tifid. Veins costaeform, pinnate ; venules anastomosing, forming 

 irregular hexagonoid areoles. Sporangia produced on the 

 apices of 4-5 venules, converging in the sinus of the lacunas, 

 forming an arcuate sorus in each sinus. Indusium linear, 

 lunulate. 



1. L. Lindeniana, Hook. Sp. Fil 2, t. 89 ^.Tropical 



America. 



2. L. pubescens, Willd. ; Hook. Gen. Fil. t. 68 A. 



Mauritius. 



TRIBE VIIL BLECHNE^. 



Sori intramarginal, medial or costal, transverse oblong linear, 

 continuous or interrupted. Indusium lateral, linear, exteriorly 

 attached, plane or vaulted, rarely obsolete. Fronds uniform, or 

 the fertile contracted. 



100. BLECHNUM, Linn. ; Presl. 



Vernation fasciculate, erect, caudiciform or CEespitose. 

 Fronds simple, pinnatifid or pinnate, from a few inches to 4-6 

 feet high ; pinnae adherent or articulated with the rachis. Veins 

 forked ; the sterile venules free, or their apices thickened and 

 forming a cartilaginous margin ; the fertile veins combined near 

 their base by a transverse, continuous, sporangiferous receptacle, 

 constituting a linear, costal, or rarely extra-costal sorus. Indu- 

 sium linear, plane. 



* Apices of the venules free. 

 f Sori costal. (Blechnum, Presl.) 



1. B. Lanceola, Sw. ; Lodd. Cab. (1592) ; Hook. Bot. Mag. 



t. 3240 ; Kunze, Fil. t. 57, /. 1 ; Hook. Ic. PI. t. 970. 

 B. lanceolatum, Radd. Fil. Bras. t. 60, /. 3. B. tri- 

 foliatum, Kaulf. Brazil. 



2. B. polypodioides, Radd. Fil. Bras. t. 60, /. 2; Kunze, 



Fil. t. 58, /. 1 ; Lowe's Ferns, 4, t. 34. Brazil. 



