Class XXIV. Otder L 



CRYPTOGAMIA. 



FILICES. 



284. POLYPODIUM. 

 POLYPODIUM VULGARE. L. Common Polypodij. 



Frond pinnatificl ; segments linear-oblong, ob- 

 tuse, slightly serrate. 



A handsome fern, not uncommon on the sides of rock^s and 

 steep shady hills, forming beds by means of its creeping roots. 

 The stalk or stipe is perfectly smooth, grooved on the upper 

 side. Fronds about half a foot long, divided in a pinnate man- 

 ner almost to the stalk or midrib, by sinuses which are more 

 acute than in the European variety. Segments of the frond ob- 

 long, parallel, rounded at the end, very slightly serrate, furnish- 

 ed on the back with a double row of large, round, yellowish, 

 granular, naked dots of fructification. Perennial. 



285. ASPIDIUM. 

 ASPIDIUM ACROSTICHOIDES. MM. Terminal Shield fern. 



Stipe chaffy ; frond long, pinnate, its divisions 

 alternate, subsessile, auriculated on one side at 

 base, slightly serrate, ciliate ; only the upper ones 

 fruitful. Mich, sub syn. 



Syn. J\"EPHRODIUM AcRosficnoiDES. Mich. 



Remarkable for the difference between its lower and upper 

 leaves. The stipe is covered with loose, membranous, chaffy 

 scales. The leaves or pinnae are numerous, oblong, somewhat 

 acute, edged with small, mucronate serratures, furnished with 

 an angular lobe on their upper side at base. The lower leaves 



