LINDMAN, AMERICAN SPECIES OF TRICHOMANES SM. 



OD 



spurious veinlets almost as long and interrupted as the ge- 

 nuine ones; tig. 21. 



In the more developed fronds, with distinct lobes, there 

 are a few strong secondary veins proceeding from the sorife- 

 rous midrib, each of them again forming the midrib for a 

 group of very slender veinlets, which are intermixed, as al- 

 ready stated, with a copious number of straight, parallel ve- 



Fig. 21. Trichomayie.s pusillum Sw.. the same i)lants as in üjr. 'M (Swartz's 



original specimen from Jamaica): A two large fertile fronds and two very 



young ones of various outline (X 10): B cellular structure of diflerent fertile 



fronds, and C of an old sterile frond (X 175). 



nules, all equal, but the greater part short or interrupted, 

 free, or unconnected, and densely crowded round the margin. 

 The consistence is firm, and the frond not so thin and 

 tran.sparent as in the following species (Trich. sphenoides and 

 its allies). 



