70 



THE BOOK OF CHOICE FERNS. 



P. (Platyloma) sagittata — Plat-yl-o'-ma ; sag-it-ta'-ta (arrow-shaped), 



Moore and Houlston. 

 This greenhouse species, of erect habit and of a somewhat deciduous 

 nature, is the Pteris sagittata of Cavanilles, and the Allosorus sagittatus of 

 Presl. It is a native of Mexico, and is closely allied to P. cordata, and 



nearer still to the variety Jlexuosa, but its fronds 

 are not zigzag, and the habit, instead of being 

 drooping, is upright. Lowe states that P. sagittata 

 was raised from spores at the Koyal Gardens, 

 Kew, in the year 1842. Its fronds, triangular and 

 bipinnate (twice divided to the midrib), are pro- 

 duced from a short-creeping rhizome, and borne 

 on pale brown or straw-coloured stalks Sin. to 

 12in. long. They are IJft. to 2ft. long, and their 



Fig. 25. Portion of Fertile Frond of stalked pinnules (leafits), smooth and of a glaucous 

 Peilsea sagittata /-,-,., 



(bluish-green) colour and soit, papery texture, have 



the singular property of rolling their margins under, 



and thus becoming quite arrow-shaped when fertile (Fig. 25) ; in the barren 



state these leaflets are heart-shaped. — Lowe, Ferns British and Exotic, iii., 



t. 28. Hooker, Synopsis Filicum, p. 153, as a variety of P. cordata. 



P. (Cheiloplecton) Seemanni — Cheil-op-lec'-ton ; See-man'-ni (Dr. 

 Seemann's), Hooker. 

 A greenhouse species, native of Mazatlan, Mexico. It is very Hke 

 P. auriculata in habit and general appearance, differing from that species 

 principally in its finer venation and narrower involucre. — Hooker, Species 

 Filicum, ii., p. 141, t. 117b. 



P. (Cheiloplecton) Skinneri — Cheil-op-lec'-ton ; Skin'-ner-i (Skinner's), 

 Hooker. 

 This stove species, native of Guatemala, is of medium size, its broadly- 

 triangular fronds, 6in. to 12in. long, 4in. to Sin. broad, and three times cut 

 down nearly to the midrib, being borne on stout, erect stalks 6in. to 9in. 

 long, pale brown or straw-coloured, and slightly hairy. The lowest leafits, 

 lin. to 2in. long and lin. broad, are cut down nearly to the rachis into 



