630 
F1LICES. (FERNS.) 
short stalk, rhombic-ovate , very obtuse (2"-4" long), cut into 3-7 
rounded or somewhat wedge-shaped lobes. — Rocks, Little Falls, New 
York, Dr. Vasey! To be sought farther northward, being also an arc¬ 
tic species. 
14. DRYOPTERIS, Adans., Schott. Wood-Fern. 
Fruit-dots round, borne on the back or near the apex of the sim¬ 
ple and free pinnate veins or their forks. Indusiura flattish, 
rounded-kidney-shaped, fixed at the sinus, opening round the mar¬ 
gin. — Fronds 1 - 3-pinnate, of thin or thinnish texture. (An an¬ 
cient name, composed of 8pvs, an oak , or tree in genet'al , and 
7 TT€pls, Fern; growing in woods.) 
§ 1. THELfPTERis, Schott (not of Presl.). — Veins simple and straight 
or simply forked. (Fronds annual: stalks and creeping rootstocks 
nearly naked ) 
1. 1>. TlielyptcriS. Frond pinnate, lanceolate in outline; 
the horizontal pinnae gradually diminishing in length from near the buse 
to the apex , sessile, linear-lanceolate, deeply pinnatifid, with oblong 
nearly entire obtuse lobes, (or appearing acute from) the margins 
strongly revolute in fruit; veins mostly forked , bearing the crowded 
fruit-dots ( soon confluent) near their middle. (Polypodium Thelypt., 
L. Aspidium, Swartz. Lastraia, Presl.) —Marshes, common. Aug. 
— Stalk 1° long or more, usually longer than the frond, which is of 
thicker texture than in the next, slightly downy ; the fruit-dots soon 
confluent and covering the whole contracted lower surface of the 
pinnae. 
2. I>. Noveboracensis. Frond pinnate, oblong-lanceolate in 
outline , tapering below from the lower pinnae (2 - several pairs) being 
gradually shorter and bent downwards; lobes fiat , broadly oblong, 
their veins all simple except in the lowest pairs, bearing scattered 
fruit-dots ( never confluent) near the margin. (Polypodium Novebora- 
cense, L. Aspidium thelypteroides, Swartz.) —Swamps and moist 
thickets, common. July. — Frond pale green, delicate and membra¬ 
naceous, nearly agreeing with the last, except in the points men¬ 
tioned. 
§ 2. La strata, Bory. — Veins more than once forked or somewhat 
pinnately branching. ( Fronds , at least the sterile , usvcdly lasting 
through the winter: stalks chaffy : rootstocks scaly-thickened.) 
* Fronds verging to 3-pinnate , viz. 2-pinnate , the pinnules pinnatifid . 
3. I>. intermedia. Frond ovate-oblong in outline (l°-2° long, 
lively green, smooth) ; pinnules oblong-linear , obtuse , horizontal , 
crowded, the lower deeply pinnatifid into linear-oblong obtuse lobes 
which are sharply cut-toothed, the upper cut-pinnatifid or incised, 
