CLASS XXIV. ORDER I. 421 



nearly globular, enclosing the fruit, and forming a sort of raceme. 

 — Low grounds. — Perennial. 



429. STRUTHIOPTERIS. 



Struthiopteris Pennsylvanica. Willd. Ostrich Fern. 



Barren fronds twice pinnate; segments entire, ob- 

 tuse, the lowest elongated, acute. 

 Syn. OxocLEA nodulosa. Schkuhr. 



One of our largest native ferns. Stipe of the barren frond re- 

 markably channelled or hollowed out in front. Divisions of the 

 frond pinnatifid, the segments curved forward and subacute, 

 those next the stipe curved backward, falcate and acute. Fer- 

 tile frond a sixth part as large, composed of a multitude of dense, 

 turgid, brownish segments, the edges recurved, and the back cov- 

 ered with fruit. — Low grounds, Hanover, New Hampshire^ 



430. ASPLENIUM. 

 AsPLENiuM RHizopHYLLUM. L. Walking Leaf. 



Frond lanceolate, stipitate, subcrenate, auricnlate- 

 cordate at base, the point very long, linear, rooting. 



A curious fern, striking root at the extremity of the frond, from 

 which root new plants arise. — In rocky woods in the western 

 parts of the state. 



A.SPLENIUJI TRiCHOMANES. Mx. Divarf Splccuwort. 



Frond pinnate: divisions roundish, crenate, wedge 

 shaped at base. 

 Syn. AsPLENiuM melaxocaulon. Muhl. 



An extremely small and delicate fern. Frond pinnate. Stipe 

 smooth, of a shining black color. Divisions or leafets sessile, 

 nearly round, crenate upon their outer edge, entire and acute 

 at base. Fructification in about five or six linear, diverginf^ 

 dots, which become roundish when old. — Found among high, 

 shady rocks in Roxbury. — Perennial. 



On comparison of the European with the American plant I do 

 not find any specific diiference. 



36 



