200 CHAEACTEKS OF TRIBES AND GENEEA. 



a good deal in outline, as above noted, and varying in the 

 presence or absence of the involucre, whether from being 

 quickly deciduous, or, as I apprehend, its entire suppression 

 at times, it is hard to say." From this view I differ, for, 

 in cultivated plants of P. planiagineum, as well as in many 

 herbarium specimens of the same that have come under 

 my notice, I found no traces of indusium, and therefore 

 consider it to be normally absent ; it consequently comes 

 under the genus Dryomenes, while P. sinuata not only 

 differs in the general outline of the frond, but also in the 

 sori being furnished with a large peltate indusium, and 

 as it agrees in general habit with P. Singaporiana, I 

 therefore associate it with that species. 



104. AspiDiuM, Sw., ill part (1800). 

 Hool., Sp. Fil. 



Vernation fasciculate, erect. Fronds trilobed, pinnate, 

 bipinnatifid or bipinnate, 1 to 4 feet high, ultimate segments 

 generally broad and flaccid. Primary veins costasform^ 

 venules simply or compoundly anastomosing. Peceptacles 

 compital or often on the apex of free veinlets, terminating 

 in the areoles. (Son round. Int?»sm))i orbicular or reniform. 



Type. Aspidiuni trifoliatum, Sw. 



lllust. Schott., Gen. Fil., t. 4 ; Hook, and Bauer, Gen. 

 Fil., p. 33 ; Moore, Ind. Fil., p. 65, B ; J. Sm., Ferns, 

 Brit, and For., fig. 70 ; Hook., Syn. Fil., t. 6, fig. 43, d. 



Obs. — This g-enus consists of between twenty and thirty 

 species of strong-growing Perns, generally with mem- 

 braneous flaccid fronds. They are widely distributed 

 throughout the West Indies, Tropical America, West 

 Africa, Mauritius, Ceylon, India, Malayan, Philippine, and 

 Polynesian Islands. 



