HROGENOUS PLANTS. 621 
St. Peter’s. Panicum pauciflorum, (Ell.) Panicum virgatum, (L.) Cenchrus echinatus, (L.) Burr 
grass. Sandy soil. Iowa. Andropogon furcatus, (Mubl.) Dry prairies. Common. Sorghum 
nutans, (Gray.) Dry soil. Iowa and Minnesota. 
ZEROGENS. 
EQuisETACEH.—Equisetum arvense, (L.) April. Damp places. Common. Equisetum sylvaticum, 
(L.) May. St. Peter’s. EHquisetum limosum, (L.) Shallow water. St. Peter’s and St. Croix. Equi- 
setum hyemale, (L.) Scouring rush. Very abundant, and rank, on the wooded banks of the St. Peter’s, 
above high-water mark. Equisetum variegatum, (Schleicher.) Margins of Montreal River, Lake Supe- 
rior. Equisetum scirpoides, (Michx.) Deep woods. St. Croix. 
Finices.—Polypodium vulgare, (L..) Crevices of exposed rocks of every character. St. Peter’s and 
St. Croix. Polypodium Phegopteris, (L.) Damp woods. St. Croix. Polypodium Dryopterus, (L.) 
Damp woods, under the shade of evergreens. St. Croix and Lake Superior. Struthiopteris Germanica, 
(Willd.) Alluvial soil, exceedingly rank on the bottoms of the Lower St. Peter’s. Allosorus gracilis, 
(Presl.) Shaded rocks, Davenport, Iowa, Blue Earth River, head of Lake St. Croix. Pteris Aquilina, 
(L.) Common brake. Dry soil. Pteris atropurpurea, (.) Attached principally to the Magnesian 
Limestones, Upper and Lower. Adiantum pedatum, (L.) Maiden-hair. Common. Camptosorus rhi- 
zophyllus, (Link.) Walking fern. Shaded and detached rocks, Falls of St. Croix. This fern sends forth 
roots at the extremity of each prolonged leaf, producing a bunch similar to the parent root, whence its 
name of walking-fern. Asplenium thelypteroides, (Michx.) Shady woods. St. Croix. Asplenium 
Filix-foemina, (R. Br.) Moist woods. Common. Cystopteris bulbifera, (Bernh.) Wet rocks. Blue 
Earth River. Cystopteris fragilis, (Bern.) Shaded cliffs, St. Peter’s and St. Croix. Woodsia obtusa, 
(Torr.) Trap-rocks. Falls of St. Croix. Woodsia Ilvensis, (R. Br.) Exposed granite and quartzite 
rocks. Upper St. Peter’s. Cheilanthes vestita, Willd.) Rocks. Falls of St. Croix. Dryopteris Thelyp- 
teris, (Gray.) Moist thickets. St. Croix. Dryopteris dilatata, Gray.) Ravines. Falls of St. Croix. 
Dryopteris cristata, (Gray.) Alder swamps. St. Croix. Aspidium fragrans, (Sw.) Trap-rocks. Falls 
of St. Croix. Frond bipinnate, oblong-lanceolate ; pinne oblong, slightly tapering to a very obtuse point, 
regularly opposite and alternate, closely set on the stipe ; pinules oblong, obtuse, round-toothed. Sori 
attached in two rows, corresponding to the lobes formed by the teeth, nearer the midrib than margins of 
the pinne, mostly covering the lower surface of the frond; stipe thickly clothed at its lower part with 
brownish, unequal, ovate-acuminate scales. The whole fern beset with fragrant, glandular hairs. Grow- 
ing in dense tufts, in the shaded crevices of trap-rocks, with the withered remains of several years’ growth 
still adhering. The fronds are of a deep green colour above, paler below, four to nine inches high. The 
aroma is permanent and agreeable. I am informed by Dr. Torrey that this species has never before 
been found within the limits of the United States, but has been obtained in British America and Kam- 
schatka, where it is used for making tea. In the locality here specified, it is quite abundant. Polysti- 
chum acrostichoides, (Schott.) Shady river-banks. Davenport, Towa, and Fort Snelling. Onoclea 
sensibilis, (L.) Moist, springy places. Common. Osmunda spectabilis, (Willd. ) Swamps. Upper 
St. Croix. Osmunda Claytoniana, (L.) Rich hillsides. St. Croix. Botrychium lunarioides, (Sw.) 
Low grounds. St. Croix. Botrychium Virginicum, (Sw.) Rich woods. St. Peter’s. ; 
Lycoroprace&.—Lycopodium lucidulum, (Michx.) Deep woods. St. Croix. Lycopodium annotinum, 
(L.) Woods. Lake Superior. Lycopodium clavatum, (L.) Upper St. Croix. Lycopodium dendroi- 
deum, (Michx.) Upper St. Croix. Lycopodium complanatum, Ge) Pine barrens. St. Croix. Sela- 
ginella rupestris, (Spring.) Exposed granite rocks, Upper St. Peter’s; trap rocks, Falls of St. Croix. 
Muscr.*—Sphagnum cymbifolium, (Ehrh.) Cranberry marshes. Dicranum scoparium, (Hedw.) 
Lake Superior. Leucobryum vulgare, (Hampe.) Trap rocks. St. Croix. Atrichum angustatum, 
(Beauy.) Lake Superior. Bartramia pomiformis, (Hedw.) Montreal River. Mnium punctatum, 
(Hedw.) Cedar swamps. St. Croix. Mnium affine, (Blandon.) Decaying logs. gfe Bera 
Bryum roseum, (Schreb.) Lake Superior. Isotherum minus, (Beauv. ) Adhering to the oa ‘ t e 
Swamp Ash. Hypnum populeum, (Hedw.) Red sand-rock. Lake Superior. Hypnum Schreberi, 
* Determined by William S. Sullivyant, of Columbus, Ohio. 
