550 PROCEEDINGS OF THE ACADEMY OP [Oct., 



2. Pteridium aquilinum (L.) Kuhn. 



Frequent on dry upland, open or about edges of thicket. 

 Delaware. — Bear Hill; Williamson; Lenni; Wawa. 

 Chester. — Sugartown Barrens; West Chester. 



3. Asplenium platyneurox (L.) Oakes. 



Frequent on dry or rocky barrens, or open woodland. 

 Delaware. — Fawkes Run; Preston Run; Bear Hill; Wawa. 

 Chester. — Sugartown Barrens; Cedar Barrens; West Chester; 

 Sconnelltown ; Brinton's Quarry; Unionville. 



4. POLYSTICHUM ACROSTICHOIDES (Michx.) Schott. 



Frequent on shaded banks and in border-woodland. 

 Delaware. — Fawkes Run; Bear Hill; Barrens of Middletown. 

 Chester. — Cedar Barrens. 



|5. Dexxst.edtia puxcticuloba (Michx.) Moore. 



Frequent in border-woodland. 



Delaware. — Williamson. 



Chester. — Cedar Barrens; Unionville. 



f6. PlXUS VTRGINIANA Mill. 



A few trees in one locality, on dry open barrens. 

 Chester. — Serpentine Ridge. 



f7. Pixus rigida Mill. 



Only on State-line Barrens, where abundant on dry upland. 

 Chester. — Nottingham Barrens. 



5. JUXIPERUS VTRGINIANA L. 



Frequent mainly in depressions of upland, greenbrier thickets. 

 Chester. — Cedar Barrens; West Chester; Unionville. 

 — Nottingham Barrens. 



9. Typha axgustifolia L. 



Scarce; in a quarryhole and pool. 

 Delaware. — Williamson; Lenni. 



10. Axdropogox scoparius Michx. 



Abundant on dry open barrens. Two forms, but hardly separable. 

 A brownish, much tufted and branched form, and a glaucous, pur- 

 plish, less tufted, and branched, taller and more wand-like form — 

 both forms abundant and growing together, the latter seemingly 



