SMITHSONIAN INSTITUTION
UNITED STATES NATIONAL MUSEUM

CONTRIBUTIONS.

FROM THE

UNITED STATES NATIONAL HERBARIUM

VOLUME 21

FLORA OF THE DISTRICT OF COLUMBIA
AND VICINITY |

By A. S. HITCHCOCK and PAUL Cc. STANDLEY

WITH THE ASSISTANCE OF THE BOTANISTS
OF WASHINGTON

WASHINGTON
GOVERNMENT PRINTING OFFICE
1919

FLORA OF THE DISTRICT OF COLUMBIA.

ADVERTISEMENT.

The United States National Herbarium, which was founded by the
Smithsonian Institution, was transferred in the year 1868 to the
Department of Agriculture and continued to be maintained by that
department until July 1, 1896, when it was returned to the official
custody of the Smithsonian Institution. The Department of Agri-
culture, however, continued to publish the series of botanical reports
entitled “Contributions from the United States National Herba-
rium,” which it had begun in the year 1890, until, on July 1, 1902,
the National Museum, in pursuance of an act of Congress, assumed
responsibility for the publication. The first seven volumes of the
series were issued by the Department of Agriculture.

W.. veC. RAvVENEL,
Administrative Assistant to the Secretary,
in charge of the (nited States National Museum.

ea

SMITHSONIAN INSTITUTION
UNITED STATES NATIONAL MUSEUM

CONTRIBUTIONS

FROM THE

UNITED STATES NATIONAL HERBARIUM

VOLUME 21

FLORA OF THE DISTRICT OF COLUMBIA
AND VICINITY

By A. S. HITCHCOCK and PAUL C. STANDLEY

WITH THE ASSISTANCE OF THE BOTANISTS
OF WASHINGTON

WASHINGTON
GOVERNMENT PRINTING OFFICE
1919

BULLETIN OF THE UNITED STATES NATIONAL MUSEUM.

PREFACE.

To a person walking in the country in search of rest from labor
the wild plants are very friendly if he has a speaking acquaintance
with them. Such an acquaintance is of untold value as a means of
rest and recreation. Yet to most persons our books on botany,
instead of opening the path to knowledge, close it with the barrier
of technical language. Botanical science is beginning to recognize
the prohibitive effect of this barrier and to take steps to open the
path to the public. The Flora of the District of Columbia and
Vicinity now presented for publication is provided with keys;to the
families, genera, and species, and in the preparation of these} keys
common words have been used extensively as substitutes for tech-
nical and unusual words. This is especially true of the key to the
families, which is so written that a person with almost no knowled¢e
of botany can trace a strange plant to its proper family. The
identification of many of the native species is made still easier. by
the illustrations, and it is only the limitation of space and cost
that has prevented the more extensive use of these photographic
reproductions.

FREDERICK V. COVILLE,
Curator of the United States National Herbarium.

5

‘CONTENTS.

Introduction ........ cc cece cece eee r eee e ene e eee n nee e nena seen ene eee sees
Systematic treatment of the vascular plants..........-.-..2--2e-ee sees cence
Key to the families based mainly on vegetative characters..........--.-
Key to the families based mainly on floral characters............-------
Annotated list of species.... 2... 2.2... cence eee cece eee eee eee ee eeeee

PLATE

ILLUSTRATIONS.

PLATES,

1. Paint Branch, at bridge on main road east of Lewiston. (Frontis.)
2. Drive near Piney Branch, Rock Creek Park. Tulip trees at right.
3. Northwest Branch, northeast of Blair School.
4, Difficult Run, looking out upon the Potomac.
5. A rocky gorge in Difficult Run.
6. The Potomac below Great Falls. Looking up the river from the mouth
of Difficult Run.
7. An old channel of the Potomac below Great Falls, looking downstream,
the main Potomac in the distance.
8A. The Chesapeake and Ohio Canal below Broadwater, looking upstream.
A walk along the towpath of this canal, from Cabin John to Great Falls,
affords a fine opportunity for viewing the scenery of the upper Potomac
and for collecting botanical specimens.
8B. The Great Falls of the Potomac from the Virginia side.
9. Woods along the flood plain of Cabin John Run in April. The home of
such spring flowers as spring beauty, trout lily, and pepper-root.

10. Marsh near Dyke. Mostly Scirpus and other sedges in the foreground.

11. Cinnamon fern (Osmunda cinnamomea), common in marshes. Spring

stage, as the fronds are unrolling.

12. Christmas fern (Poly ystichum acrostichoides). Woods.on hilltop near Difficult

Run, a tulip tree in middle distance.

13. Wild rice (Zizania palustris). An extensive marsh in the upper part of

the lower Eastern Branch.

14. Skunk cabbage (Spathyema foetida), along Cabin John Run in April. The
lurid ill-smelling flowers appear before the leaves in February, being
the earliest of our distinctively spring flowers.

15A. Spiderwort ( Tradescantia virginiana). Common along the upper Potomac
in May; the purplish blue petals open in the morning but wither by
midday.

15B. Crested iris (Zris cristata). Low rocky woods along the Potomac above
Washington.

16. Marsh near Dyke. Pickerel-weed (Pontederia cordata) in foreground, the

flowers blue.

17A. Spring beauty (Claytonia virginica). Common in moist woods in early
spring. Flowers whitish with pink veins.

17B. Trout lily (Erythronium americanum). Common in moist woods in early
spring. Flowers yellow.

18A. Blue phlox (Phlox divaricata). Moist woods along the Potomac in May.

18B. Wake-robin (Trillium sessile). Common in rich woodland along the upper
Potomac, the flowers dark purple or sometimes green.

19A. Bellwort (Uvularia sessilifolia). Common in woodlands below the fall
line in April and May, the flowers greenish yellow.

19B. Blue flag (Iris versicolor). Bogs and marshes, in May.

10

ILLUSTRATIONS,

- 20A. Showy orchis (Orchis spectabilis). Widely distributed in rich woods in

late spring, but not abundant. Flowers pink and white.

20B. Moccasin flower (Cypripedium acaule). A characteristic plant of sandy
pine woods in May, the saclike lip rosy purple, mottled.

21. Lizard’s-tail (Saururus cernuus), ina swamp near Dyke. A characteristic
summer marsh plant with white flowers.

22A. Pin oak (Quercus palustris) in May, the leaves partially developed. The
decurved lower branches are characteristic of this species.

22B. Red oak (Quercus maxima) in May.

23. White oak (Quercus alba) in May, a last year’s growth of Andropogon
elliottti in foreground.

24. Yellow pondlily (Nymphaea advena) in shallow water near Dyke. Abun-
dant in the marshes of the Eastern Branch and the lower Potomac.

25A. Hepatica (Hepatica americana). Common in rich woods in March and
April. Our earliest showy spring flower.

25B. Cream violet (Viola striata). Low woods along the Potomac in April

and May.

26. May-apple (Podophyllum peltatum), common in rich woods in spring;
flowers white. Below is the three-leaved stonecrop (Sedum ternatum),
frequent in rocky woods; flowers white.

27. Sassafras (Sassafras varitfolium), as it occurs along old fence rowsin the Oxon

Run valley.

28A. Bloodroot (Sanguinaria canadensis); common in rich woods in March
and April. One of our earliest spring flowers; petals waxy white;
juice of plant orange-red.

28B. Twin-leaf (Jeffersonia diphylla); rich woods on islands of the Potomac
in April. Leaves split into two equal parts; flowers white.

294. Dutchman’s breeches (Bikukulla cucullaria). Rich woods along the

upper Potomac in April; flowers white, tinged with pale yellow.

29B. Squirrel corn (Bikukulla canadensis). Resembling Dutchman’s breeches
but less common; flowers white, tinged with pink.

30A. Pepper-root (Dentaria laciniata). Moist woods in April and May, the
flowers white or pinkish.

30B. Saxifrage (Savifraga virginiensis). Common in rocky woods in April;
flowers white.

31A. Wild strawberry (Fragaria virginiana). Common in fields and open
grassland in May; flowers white.

31B. Star chickweed (Alsine pubera). Common in April and May in rocky
woods, the flowers white.

32. Goat’s-rue (Cracca virginiana); woods near Great Falls. Common in sandy

or rocky woods in May and June.

33. Black locust (Robinia pseudo-acacia) in May, just as the leaf buds are open-
ing. An abundant, probably naturalized tree with handsome racemes
of white fragrant flowers in early summer.

34A. Squaw-root (Conopholis americana). Rich woods in May. <A brownish
root parasite, four to eight inches tall.

34B. Prickly pear (Opuntia vulgaris), on rocks at Plummers Island. This
specimen shows the fruit; the yellow flowers appear in June. Our
only native cactus.

35. Flowering dogwood (Cornus florida), A small woodland tree, the white

petal-like bracts conspicuous in the spring before the leaves appear.

ILLUSTRATIONS. 11

36. Pinesap (Hypopitys lanuginosa). Rich woods in summer, the plants tawny
or pinkish. In the center is a frond of the Christmas fern (Polystichum
acrostichoides); against the middle of the log is a frond of maidenhair
(Adiantum pedatum); the other ferns are beech ferns (Dryopteris
hexagonoptera).

37A. Ghost-pipes (Thalesia uniflora). Moist woods in May. A root parasite, the
flowers yellowish or bluish.

37B. Trailing arbutus (Epigaea repens). Sterile woods in March and April.
Flowers pinkish.

38. Thicket of laurel (Kalmia latifolia), along Cabin John Run in April.

Leaves evergreen.

39. Laurel (Kalmia latifolia). Flowers white or pink. At first the anthers
are held in little cavities at the side of the corolla; later the elastic
filament straightens, suddenly releasing the anthers and throwing the
pollen upon a visiting bee.

40. Deerberry (Polycodium stamineum). A characteristic shrub in sterile
woods; flowers white.

41A. Bluets (Houstonia coerulea). Open sterile woods in April and May.
Flowers pale blue or nearly white, with a yellowish center.

41B. Robin’s plantain (Hrigeron pulchellus). Common in meadows and open

“ woods in April and May. Ray flowers bluish.

42. Japanese honeysuckle (Lonwera japonica), climbing on a dead tree. An
introduced vine now abundant along fence rows and edges of woods, and
on banks. Flowers white, fading to cream, sometimes pink.

TEXT FIGURE.
Page.

Figure 1. The inflorescence, spikelet, and floret of a grass (Bromus secalinus).. 66

FLORA OF THE DISTRICT OF COLUMBIA AND
VICINITY.

By A. 8. Hrrcacocx and Paut C. STANDLEY.

INTRODUCTION.

For many years the botanists of Washington have had under
consideration the project of preparing a flora of Washington to
replace the excellent work of Lester F. Ward, entitled ‘Guide to
the Flora of Washington and Vicinity,’”’ published in 1881 as Bulletin
26 of the United States National Museum. This work and other
papers relating to the local flora are reviewed interestingly by Mr.
P. L. Ricker in a recent paper summarizing botanical activity in the
District of Columbia.’

According to Mr. Ricker, the first list of the plants of our region
was included in the Florula Columbiensis.2 The second list was
compiled by John A. Brereton * and was based upon investigations
made from 1825 to 1830 by the Botanical Club of Washington. In
1876 the Potomac Side Naturalists’ Club issued the Flora Colum-
biana ‘ in Field and Forest.

The best known account of our flora is that by Lester F. Ward,®
mentioned above, usually known as Ward’s Flora. There were six
supplements to this. In 1906 the names of the flowering plants

1 A sketch of botanical activity in the District of Columbia. Journ. Washington
Acad. Sci. 8: 487, 516. 1918.

2 Florula Columbiensis: or alist of plants found in the District of Columbia. Printed
for the Washington Botanical Society. 1819.

3 Florae Columbianae prodromus. 1830.

4 Flora Columbiana. A catalogue of the plants growing without cultivation in the ©
District of Columbia. By Dr. George Vasey, Prof. J. W. Chickering, Dr. E. Foreman,
Prof. Wm. H. Seaman, and Mr. L. F. Ward, Committee of Potomac Side Naturalists’
Club. Field & For. 1: 83-87. 1876. 2: 13-15; 31-33; 45-46; 61-84; 86-88; 103-105. 1876.
Includes 1,083 species. Addenda, op. cit. 3: 145-164. 1878. Includes 112 species.

5 Bull. U. S. Nat. Mus. 26. Pp. 1-264, with map. 1881.

6], Ward, Lester F. List of plants added to the flora of Washington from April 1,
1882, to April 1, 1884. Proc. Biol. Soc. Washington 2: 84-87. 1884.

_ 2. Knowlton, Frank H. Additions to the flora of Washington and vicinity from
April 1, 1884, to April 1, 1886. Op. cit. 8: 106-132. 1886.

3. Holm, Theodor. Third list of additions to the flora of Washington, D.C. Op.
cit. 7: 105-132. 1892. .

4, Holm, Theodor. Fourth list. Op. cit. 10: 29-43. 1896.

5. Holm, Theodor. Fifth list. Op. cit. 14: 7-22. 1901.

6. Steele, Edward S. Sixth list of additions to the flora of Washington, D. C.;

and vicinity. Op. cit. 14: 47-86. 1901. 13

14 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

and ferns of Ward’s Flora and of the several supplements were
included by Mr. P. L. Ricker in ‘A List of the Vascular Plants of the
District of Columbia and Vicinity,’ mimeographed copies of which
were distributed among Washington botanists. Besides these there
are many articles dealing with certain groups, a list of which papers
is included in the bibliography appended to Mr. Ricker’s account
referred to above.

The plan of the present Flora was announced at the annual meeting
of the Botanical Society of Washington in the spring of 1915. This.
plan involved the cooperation of 28 botanists under the leadership
of Frederick V. Coville and A. S. Hitchcock, each being responsible.
for certain families or genera. During the first season keys to the-
genera and species of nearly all the families were prepared by the.
contributors and mimeographed copies were distributed, in order
that they might be tested for one collecting season. The contribu-
tors prepared the finished: manuscript in 1917. In 1916 Mr. Coville.
withdrew from active participation in the work and the leadership.
was assumed by A. S. Hitchcock and Paul C. Standley.

Following is a list of the persons who have contributed the final.
text and of the groups assigned to each.

Batt, C. R.: Saltz.

BuakeE, 8. F.: Juncageae (in part).

Cuask, AGNEs: Poaceae (in part), Cyperaceae (except Carex), Xyridaceae, Eriocaula-
ceae, Ceratophyllaceae. —

CoviL.e, F. V.: Juncaceae (in part), Ericaceae, Vacciniaceae.

Eaacieston, W. W.: Malaceae.

Hintiman, F, H.: Cuscutaceae.,

Hircncock, A. E.: Solanaceae.

Hircucock, A. 8.: Poaceae (in part), Podostemaceae, Penthoraceae, Saxifragaceae,
Hydrangeaceae, Escalloniaceae, Grossulariaceae, Hamamelidaceae, Platanaceae,
Rosaceae, Amygdalaceae, Aceraceae, Clethraceae, Pyrolaceae, Monotropaceae.

LewrTon, F. L.: Malvaceae.

McATEE, W. L.: Sparganiaceae, Potamogetonaceae, Naiadaceae, Pontederiaceae,.
Callitrichaceae, Caprifoliaceae.

Maxon, W. R.: Pteridophyta, Polygonaceae, Primulaceae, Orobanchaceae, Phryma-
ceae, Valerianaceae, Dipsacaceae, Campanulaceae, Lobeliaceae, Antennaria.

Norton, J. B.: Lemnaceae, Melanthiaceae, Liliaceae, Convallariaceae, Smilacaceae,
Amaryllidaceae, Iridaceae.

Norton, J. B. 8.: Commelinaceae, Euphorbiaceae.

Ross, J. N.: Crassulaceae, Cactaceae, Apiaceae.

Rosen, H. R.: Dioscoreaceae, Anacardiaceae, Hypericaceae, Elatinaceae, Cistaceae,
Lythraceae, Melastomataceae, Onagraceae, Haloragidaceae.

Sarrorp, W. E.: Magnoliaceae, Annonaceae, Lauraceae, Passifloraceae, Cucurbita-
ceae.

Skeets, H. C.: Orchidaceae.

Smita, C. P.: Asclepiadaceae, Convolvulaceae, Polemoniaceae, Hydrophyllaceae.

STANDLEY, P. C.: Araceae, Saururaceae, Urticaceae, Loranthaceae, Santalaceae,
Aristolochiaceae, Chenopodiaceae, Amaranthaceae, Allioniaceae, Phytolaccaceae,
Aizoaceae, Portulacaceae, Corrigiolaceae, Alsinaceae, Silenaceae, Nymphaeaceae,

FLORA OF THE DISTRICT OF COLUMBIA. 15

Cabombaceae, Ranunculaceae, Berberidaceae, Menispermaceae, Papaveraceae,
Fumariaceae, Brassicaceae, Capparidaceae, Sarraceniaceae, Droseraceae, Caesal-
piniaceae, Fabaceae, Geraniaceae, Oxalidaceae, Linaceae, Rutaceae, Simarouba-
ceae, Limnanthaceae, Impatientaceae, Rhamnaceae, Violaceae, Araliaceae, Corna-
ceae, Loganiaceae, Gentianaceae, Apocynaceae, Boraginaceae, Verbenaceae,
Scrophulariaceae, Bignoniaceae, Pinguiculaceae, Acanthaceae, Plantaginaceae,
Rubiaceae, Cichoriaceae, Ambrosiaceae, Asteraceae.

Tipestrom, I.:; Pinaceae, Typhaceae, Vallisneriaceae, Populus, Myricaceae, Jug-
landaceae, Betulaceae, Fagaceae, Ulmaceae, Moraceae, Aquifoliaceae, Celastraceae,
Staphyleaceae, Vitaceae, Tiliaceae, Daphnaceae, Diospyraceae, Oleaceae.

Van ESELTINE, FLORENCE I..: Polygalaceae.

Van EsE TINE, G. P.: Alismaceae, Carer, Menthaceae.

The following persons aided in the preparation of the preliminary
keys: C. V. Piper, P. L. Ricker, P. G. Russell, E. S. Steele, S. C.
Stuntz.

Two keys to families have been prepared, a natural key by Mi
Hitchcock (including keys to families of Pteridophyta by Mr. Maxon),
and an artificial key by Mr. Standley. The introduction is by Mr.
Hitchcock and the glossary by Mr. Maxon.

The introductory account of the flora of the region is not so full
as might be thought desirable. A detailed presentation of the rela-
tions of the flora to the vegetation of the surrounding areas, how-
ever, is not regarded as essential in a work intended primarily as a
classified list of the species. It is hoped that the present volume will
stimulate interest in the phytogeography of the region and serve as
a basis for an analysis of the flora by those who may have oppor-
tunity to study the subject for a longer period.

The area included by the Flora is approximately a circle of 15
miles radius, with the Capitol as the center, this area being prac-
tically that of Ward’s Flora, though it is not intended to exclude
from consideration localities that lie a short distance outside the
15-mile circle. The maritime flora of the shore of Chesapeake Bay
and of the lower Potomac River is excluded, as is also that of the
Patuxent Valley. In the main, the local area reaches to Bowie,
Upper Marlboro, and Brandywine on the east, Mount Vernon on
the south, Great Falls on the west, and Rockville and Oak Crest on
the north.

The formal list includes all indigenous plants and all introduced
ones that have become established. Many species have been collected
only once, or sometimes oftener but under circumstances which indi-
cate that they are waifs or chance introductions and are not to be
considered a part of our flora. Such species are mentioned in notes
appended to an allied species or genus. It has not always been
possible definitely to determine whether these stray individuals are
to be considered a part of our flora, and the decisions in this respect
may not be consistent; but rare specimens of species native in this
general region may usually be assumed to be indigenous, while those

with

16 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

that belong to introduced species may require proof that they are
established.

All the species admitted to the formal list are based upon specimens
in the District Flora Herbarium, which has been segregated from
the main collection of the National Herbarium. Species reported !
but which are not supported by specimens have been mentioned in
notes. All the species listed in Ward’s Flora and its Supplements
have been accounted for, even though they can not now be verified
by specimens. Some of these are accounted for by synonymy;
others are shown by the specimens to be errors of identification;
a few of which there are no specimens in the Herbarium have been
mentioned in notes.

The more commonly cultivated species have been noted under
the family or genus to which they belong. No attempt has been
made to include the vast array of ornamental plants of greenhouses
and parks, except a few of the well-known species, such as trees that
are planted along the streets.

The nomenclature is in accerd with the American Code of Botanical
Nomenclature, except that so-called duplicate binomials are not used.

Synonyms have been given where necessary to coordinate the
names with Gray’s Manual, Britton and Brown’s Illustrated Flora,
and Ward’s Flora. Errors of identification in Ward’s Flora have
been indicated thus, Hrianthus alopecuroides of Ward’s Flora.

Mr. L. V. Hallock contributed the photographs for plates 5, 8, 15,
18, 19, 20B, 25, 28, 29, 30, 31, 34, 37, 39, 41; Mr. E. lu. Crandall those
for plates 11, 17, 20A, 26, 35, 36; the photographic laboratory of the
Department of Agriculture that for plate 13; Mr. Hitchcock furnished
those for the remainder.

The geology of the region as related to the flora has been briefly
discussed by Edgar T. Wherry.? The chief physiographic feature
is the ‘fall line,”’ which separates the Piedmont Plateau on the north-
west from the Coastal Plain on the southeast, being named from the
fact that the rivers and smaller streams, flowing southeastward to the
sea, often have waterfalls or rapids near this line. On a topographic
map of the region the course of the fall line can be readily traced by
the change in the contours along the stream valleys. Northwest of
the line the streams run in narrow steep-sided gorges, the contour
lines being close together for some distance back of the stream; typical
illustrations of this are shown in plates 5, 6, and 7. Southeast of it
they have broad open valleys marked by wide spacing of the contour
lines. This is shown by the following streams: Back Lick Run and
Holmes Run near Lincolnia, Fourmile Run at Barcroft, the Potomac
River below Georgetown, Sligo Branch near Riggs School, Northwest

1 See footnotes on page 13.
? In a paper read before the Botanical Society of Washington and abstracted in the
Journal of the Washington Academy of Sciences (7: 435. 1917).

FLORA OF THE DISTRICT OF COLUMBIA. 17

Branch at Riggs Mill (Pl. 3), where the change is most strongly
marked, and Paint Branch near Paint Branch School (Pl. 1).
Characteristic Coastal Plain views are shown also in plates 10 and 13.

The geological formations of the Piedmont Plateau are chiefly
crystalline gneisses of early periods, among which may be mentioned
the Carolina gneiss, granite gneiss, diorite, biotite, granite, and basic
igneous rocks, including gabbro, meta-gabbro, and serpentine.

The Coastal Plain is occupied by unconsolidated gravels, sands,
and clays deposited during successive advances of the sea in Creta-
ceous, Tertiary, and Quaternary periods. Gravels also occur to
some extent as cappings on the hills along the edge of the Piedmont.
Bogs are frequent on the Coastal Plain and rare on the Piedmont.
Lime is often present in notable amount in the soils of the Piedmont
through concentration -by means of accumulations of leaf mold,
although there are no highly calcareous rocks in the vicinity. Acid
soils are predominant on the Coastal Plain. The relation of soils
to the floras of the two regions is illustrated by the distribution of
the lily family and its allies. Those species limited to calcareous
soils and found chiefly on the Piedmont Plateau are Allium tricoccum,
Vagnera stellata, Melanthiwm latifolium, and Trilliwm sessile. Those
limited to noncalcareous or acid soils and found chiefly on the Coastal
Plain are Aletris farinosa, Tofieldia racemosa, Melanthiwm virginicum,
and Stenanthium gramineum. The other species of the Liliales grow
throughout the region and apparently have no marked soil preference.

The floras of the two physiographic areas are noticeably different,
though there are many species common to the two regions. In the
Piedmont region there is a marked intrusion of mountain and north-
ern plants, these being found especially along the steep banks of the
Potomac and of the ravines leading into it, and along Rock Creek and
its western tributaries. The uplands, when not under cultivation,
for the most part represent land previously cultivated and now
covered with second growth forest or waste fields. The original
flora was less characteristically mountain than that which occupies the
ravines.

The Potomac Valley region is easily accessible and offers a most
convenient and delightful field for a study of the spring flora. One of
the three trolley lines extending in this direction terminates at Cabin.
John, from which the pedestrian may explore the left bank of the
Potomac and the ravines which enter the main valley at intervals
above. Though the residential district is extending up the Potomac,
there are still many ravines and banks between Georgetown and
Cabin John of interest to the collector. These may be reached from
the trolley line or from the Conduit Road, which follows this line and
continues to Great Falls. The other two of the three trolley lines

69289—19——2

18 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

connect Washington with Great Falls (Pl. 8B). They pass along the
high land skirting the heads of the ravines, one on the Maryland side,
the other on the Virginia side. By taking the trolley to a station
near the head of a ravine on the south side, one can make a trip down
the ravine to the river, along the steep bank of the river to the next
ravine, and, ascending this, return by trolley. On the north side
one may do the same, or the return can be made along the road or
towpath to Cabin John. There are four larger ravines below Great
Falls on the south side: Difficult Run (PI. 4), Bullneck Run, Scotts
Run, and Dead Run. Farther down is Pimmits Run, which enters
the main valley near Chain Bridge. On the north side a pleasant
trip can be made by getting off the trolley at Ferndale and going
down Cabin John Run to Cabin John Bridge.

The Chesapeake and Ohio Canal extends from Georgetown to Great
Falls and on to Cumberland, following the left bank of the Potomac.
The flora along the canal is of especial interest, as the original species
have been preserved from destruction by animals and from the
encroachment of agricultural operations and residential sections.
In the water of the canal and along the margin are numerous aquatic
and semiaquatic plants. The cliffs and banks are the home of many
species that are not easily accessible elsewhere. The towpath of the
canal offers to the pedestrian the most convenient road for observing
the plants of the Potomac Valley. (Pl. 8A).

Spring flowers are abundant in the valleys and on the alluvial slopes
(P1.9). The earliest species of interest to the layman is the hepatica,
soon followed by the bloodroot. Several weedy species with in-
conspicuous flowers bloom earlier in the season, or even during
the winter months, when the weather is warm, or when growing
in especially sunny or protected spots. The skunk cabbage, the
earliest of the strictly spring flowers, is found widely distributed in
our area in moist places, mostly in the woods. Other herbaceous
species with showy flowers blooming in early April are the spring
beauty, trout lily, wake-robin, twin-leaf, blue violet (Viola sororia
and V. papilionacea), cream violet (V. striata), Dutchman’s breeches,
buttercup (Ranunculus septentrionalis and R. hispidus), pepper-root
(Dentaria heterophylla and D. laciniata), harbinger-of-spring, bluebells,
Sazxifraga virginiensis, and Alsine pubera. A little later, usually the
latter part of April, will be found Phlox divaricata, wild ginger,
Jack-in-the-pulpit, columbine, golden ragwort, and cranesbill.

Among the woody plants the soft maple and the elms flower very
early, often in February and March. The red maple, ashes, box-
elder, and the catkin-bearing trees flower in April or early May.
The redbud with red flowers and the June berry with white flowers
are conspicuous in the woods before the trees produce their leaves.
Somewhat later, but before the forest has come into full leaf, the

FLORA OF THE DISTRICT OF COLUMBIA. 19

flowering dogwood attracts attention. Spice bush is abundant and
easily distinguished by the fragrance of the broken twigs. -

Along the Potomac near Great Falls there are several species not
found farther east. One of the most conspicuous of these is Phlox
subulata, common on the rocks along the towpath. Other rock
plants are Sedum ternatum, S. telephioides, and Opuntia vulgaris.
On the bluffs of the right bank of the Potomac the hemlock is an
interesting component of the forest flora.

Another region of the Piedmont easily accessible is Rock Creek
Park, where plants may be observed though they may not be col-
lected without permission (P!. 2). The ravines and slopes harbor the
original flora of the region and can be reached from many roads and
paths. There are also several interesting valleys and wooded areas
within easy walking distance of the Rockville trolley line. The
upper valleys of Paint Branch and Northwest Branch lie in the
Piedmont, but they are not easily accessible except by special con-
veyance.

The Coastal Plain region can be reached by any of the trolley
lines leading northeast, east, or south from Washington.

Between the business part of Washington and Takoma Park,
which lies about at the fall line, there are several localities men-
tioned in Ward’s Flora which have now been converted into resi-
dential districts, but the vicinity of Takoma Park itself still offers
much of interest. The trolley line to Laurel, lying in the valley of
Indian Creek and Eastern Branch or Anacostia River, opens up
fine collecting grounds. There is a long swamp or series of swamps
on the east side of the Baltimore and Ohio Railroad from Hyatts-
ville to Berwyn and on to Beltsville, the section from Berwyn to
Beltsville being known as the Hollywood Swamp. The eastern
sector of our region, lying outside the District and between the
Baltimore trolley line and the lower Potomac, is not penetrated by
electric lines, but steam railways are available. The Pennsylvania
Railroad passes through Lanham and Bowie, the latter a station at
the limit of the 15-mile circle, from which a branch extends south
through Upper Marlboro and Brandywine to the lower part of the
peninsula. The Chesapeake Beach Railroad joins a trolley line at
the eastern corner of the District and runs to Upper Marlboro and
Chesapeake Beach. <A trolley line goes to Anacostia and on south
to Congress Heights, from which point one can explore the valley
of Oxon Run and the lower left bank of the Eastern Branch. A line
of automobile busses runs from Washington to Brandywine and
beyond, passing through Silver Hill, from which the Suitland bog
may be reached, and through Camp Springs, from which one can go
by a good road to Upper Marlboro.

20 * CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Much of the region east and southeast of the District is fairly
level upland occupied by cultivated fields and correspondingly
uninteresting from a botanical standpoint, but here and there,
especially along the streams, are bits of land supporting an indigenous
flora.

One of the most interesting features of the Coastal Plain area is
the bogs. These are discussed at length by W. L. McAtee in his
“Sketch of the Natural History of the District of Columbia.’! The
bogs are there designated as magnolia bogs because one of the con-
spicuous plants found in them is Magnolia virginiana. One group
of these, known as Powder Mill bogs, lies about 2 miles west of Ulles
Crossing, a station on the trolley line south of Beltsville. There are
three bogs in the vicinity, the best of which is near the crossroads,
hidden in the woods and not visible from the road. A very interesting
one is situated about one and a half miles southeast of Suitland, and
there are several others scattered here and there. These bogs are
usually on a sloping surface near a small stream and are underlaid
with a stratum of gravel. The boggy covering may be very thin,
and there are often spots of bare wet gravel. Surrounding these
bogs is the usual forest growth, but within them the vegetation is
herbaceous except for spots or islands of shrubs. There is more or
less sphagnum and often an abundance of Panicum lucidum. Some
of the characteristic plants are: Lycopodium adpressum, Ertvophorum
virginicum, Rynchospora alba, Scleria pauciflora, Fuirena hismda,
Xyris caroliniana, Eriocaulon decangulare, Tofieldia racemosa, Hab-
enaria blephariglottis, Pogonia ophioglossoides, Limodorum tuberosum,
Habenaria clavellata, Myrica carolinensis, Magnolia virginiana, Drosera
rotundifolia and D. intermedia, Aronia melanocarpa, Amelanchier
oblongifolia, Polygala cruciata, Rhexia virginica, Azalea viscosa, Kalmia
angustifolia, Setiscapella subulata, Viburnum cassinoides, Eupatorium
verbenaefolium.

The lower Potomac region is rich in marsh plants. Much of the
upper part of the Eastern Branch or Anacostia River estuary is
occupied by an extensive marsh of Indian rice. There are marshes
bordering the right bank of the Potomac between Washington and
Mount Vernon. A convenient station for reaching this region is
Dyke, from which one can penetrate the marsh on a long dike extend-
ing into the river. Here may be found pickerel-weed, Peltandra
virginica, narrow-leaved cat-tail, yellow pondlily, pondweeds, and
many other marsh and aquatic plants. The collector of aquatic
plants should not fail to explore also the waters of the canal, where
many pondweeds are found.

In contrast with the bogs and marshes are the dry sterile woods
characterized by the presence of the laurel (Kalmia latifolia). Thick-

* Bull. Biol. Soc. Washington. Pp. 1-142. 1918.

FLORA OF THE DISTRICT OF COLUMBIA. 21

ets of this evergreen shrub are conspicuous in winter and in early
spring before the deciduous trees have produced their foliage (Plate
38). In such localities one finds several species of heaths, such as
Vaccinium vacillans, Gaylussacia baccata, Polycodium stamineum,
Azalea nudiflora, Chimaphila umbellata, and C. maculata. The
characteristic grass of such localities is Panicum ashei. Similar to
the laurel thickets are the pine and oak woods, consisting of Pinus
virginiana and Quercus marilandica. In sandy pine woods one often
finds the beautiful moccasin flower. Another type of barrens is
found in the pure forests of scrub pine occurring on both the Piedmont
and the Coastal Plain. The undergrowth is very sparse, consisting
of such plants as Pyrola secunda, the two species of Chimaphila,
Mitchella repens, and Cypripedium acaule.

Our knowledge of the flora of the Washington area is far from com-
plete. Certain parts of the area are fairly well known; other parts are,
so far as our records show, almost wholly unexplored. The best
known parts are the District itself and a rather narrow zone around
it; the valley of the Potomac from Great Falls to Alexandria for a
mile or two back from the river; and the valley of Eastern Branch
(or Anacostia River) as far as Beltsville. The unexplored parts
lie in general toward the periphery of the fifteen-mile circle, espe-
cially from Mount Vernon to Vienna, and the sector from the Penn-
sylvania Railroad to the Potomac River. The region west of
Brandywine is practically unknown botanically.

SYSTEMATIC TREATMENT OF THE VASCULAR PLANTS.

KEY TO THE FAMILIES (IN SOME CASES TO THE GENERA) BASED MAINLY
ON VEGETATIVE CHARACTERS.

I. Trees and Shrubs.

Leaves needle-like or scalelike, or narrowly linear.
Stems jointed, the joints flattened, succulent, armed with spines; fruit a juicy berry.
. CACTACEAE (p. 211).
Stems not jointed or flattened, woody, unarmed; fruit a dry cone or a berry-like cone.

PINACEAE (p. 60).
Leaves flat, broader than linear, never scalelike.

1. Leaves compound, composed of few or many leaflets.

Leaves opposite.
Stems climbing, or clambering over other plants.
Leaflets 3-7; corolla none, the 4 distinct sepals colored and petal-like; fruit of numer-

ous hairy long-tailed achenes...........-.-- RANUNCULACEAE (p. 156).
Leaflets 9-11; corolla funnelform, orange, large and showy; sepals united; fruit a
2-celled capsule 10-15 cm. long.........-..------------ Bignonia (p. 254).

Stems erect, never climbing.
Leaflets 3 or 5, never more.
Plants shrubs; leaflets 3, finely toothed; flowers perfect, white or whitish; fruit
bladder-like, 3-lobed..........-------+-++- STAPHYLEACEAE (p. 200).
Plants trees; leaflets 3 or 5, coarsely toothed or lobed; flowers pistillate and
staminate, greenish; fruit a double winged samara....-.. Rulac (p. 200)

22 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Leaflets more than 5 in most of the leaves on each plant, but some of the leaves
occasionally of only 5 leaflets.
Plants trees; flowers pistillate and staminate, usually appearing before the
leaves, in small clusters or in panicles; fruit a winged samara.
Fraxinus (p. 227).
Plants shrubs; flowers perfect, appearing after the leaves, in broad flat-topped
cymes; fruit juicy, berry-like.......................- Sambucus (p. 261).
Leaves alternate.
Stems armed with spines.
Plants trees; fruit a flat pod.
Leaves once pinnate; flowers very irregular, white or pinkish.Robinia (p. 185).
Leaves twice pinnate; flowers regular or nearly so, greenish. .Gleditsia (p. 180).
Plants shrubs; fruit not a flat pod.
Leaflets numerous; flowers in umbels arranged in panicles; fruit a black juicy
5-celled drupe...........0. 2.2. e eee eee eee ee ARALIACEAE (p. 215). -
Leaflets 3-9; flowers not in umbels; fruit red..........-. ROSACEAE (p. 173).
Stems without spines.
Leaves of 3 or 5 digitate leaflets.
Leaflets 3 (sometimes only 1), entire; plants erect; flowers showy, yellow, irreg-

ular; fruit a dry po.d................200- 202 eee eee FABACEAE (jp. 181).
Leaflets 5, toothed; plants climbing by tendrils; flowers very small, greenish,
regular; fruit a juicy black berry.................. Parthenocissus (p. 201).

Leaves pinnate, of 3 to many leaflets.
Leaflets entire, or with one or 2 teeth near the base, numerous. Trees; fruit

winged..............0000cc cece eee e eee ees SIMAROUBACEAE (p. 193).
Leaflets with numerous fine or coarse teeth, or rarely entire, the leaflets then
only 3.

Plants trees; flowers in catkins; fruit a nut. Leaflets 5 or more, aromatic.
JUGLANDACEAE (p. 135).
Plants shrubs; flowers not in catkins; fruit not a nut.
Leaflets gland-dotted, 3, nearly entire; fruit winged; erect shrubs.
Ptelea (p. 192).
Leaflets not gland-dotted, 3 to many, conspicuously toothed; fruit a dry or
slightly juicy drupe; erect or climbing shrubs.
ANACARDIACEAE (p. 198).

2. Leaves entire, toothed, or lobed, but never compound.

A. LEAVES OPPOSITE.

Plants parasitic upon the branches of trees. Leaves entire, thick and leathery.
LORANTHACEAE (p. 143).
Plants not parasitic.
Mature leaves toothed or lobed. ©
Plants trees; fruit a double samara. Leaves lobed; flowers yellow, green, or red.
ACERACEAE (p. 200).
Plants shrubs; fruit never a samara.
Flowers borne in the axils of the leaves; fruit dehiscent, deeply 3-5-lobed;
flowers greenish or purplish. Leaves finely toothed...Euonymus (p. 199),
Flowers borne at the ends of the branches; fruit a small many-seeded capsule or
a l-seeded fleshy drupe, not lobed; flowers white.
Corolla of 4 distinct petals; fruit a many-seeded capsule; leaves cordate-ovate,
finely toothed..................22..-.-. HYDRANGEACEAE (p. 172).
Corolla of united petals; fruit a fleshy 1-seeded drupe; leaves various in outline,
often lobed...........-..-..22222000000-- CAPRIFOLIACEAE (p. 259).

FLORA OF THE DISTRICT OF COLUMBIA. 23

Mature leaves entire, those on young shoots rarely lobed or toothed.
Leaves dotted with black glands, rounded at the apex. Flowers yellow; iruit a
capsule; low shrubs.........---.---+-+-+++--++-- HYPERICACEAE (p. 204).
Leaves not gland-dotted, usually pointed at the apex.
Leaves, at least the upper ones, in whorls of 3, glabrous, with stipules; flowers
in dense spheric heads. Shrubs or small trees...Cephalanthus (p. 257).
Leaves opposite, never whorled, the uppermost rarely united by their bases
and thus perfoliate; stipules none; flowers not in spheric heads.
Leaves evergreen, thick and leathery. Corolla gamopetalous, pink or red;
fruit a capsule; pedicels glandular-pubescent; large or small shrubs.
Kalmia (p. 223).
Leaves deciduous, comparatively thin.
Plants climbing or trailing vines. Leaves rounded at the apex; flowers
axillary, the corolla tubular or funnelform; fruit a several-seeded
black or red berry....--- veces cee eeteeeeeeeeees Lonicera (p. 259).
Plants erect shrubs or trees.
Leaves rounded at the apex. Flowers in axillary clusters; fruit a
2-seeded white or red berry; shrubs....-.. Symphoricarpos (p. 259).
Leaves pointed at the apex.
Blades of the leaves broadest at the base and there truncate to cordate.
Trees; leaves pubescent, large (mostly 12-25 cm. long); ‘flowers
large (about 4-5 cm. long).

Flowers purple; fruit a large ovoid capsule... .. Paulownia (p. 250).
Flowers white, spotted with yellow and purple; fruit a very long
terete capsule .....-2...-22-.---+--+----+----- Catalpa (p. 254).

Blades of the leaves broadest near or above the middle, obtuse or
usually acute or tapering at the base.
Flowers in loose or dense panicles; stamens 2. Fruit a 1-3-seeded
black berry or drupe; shrub. ..........--- OLEACEAE (p. 227).
Flowers in flat-topped cymes, or rarely in a dense head surrounded
by 4 petal-like white bracts; stamens 4 or 5.
Corolla and calyx 4-lobed; fruit 2-seeded, a blue, white, or red
berry; shrubs or trees........--------- CORNACEAE (p. 219).
Corolla and calyx 5-lobed; fruit 1-seeded, a black drupe; shrubs.

Viburnum (p. 260).
AA. LEAVES ALTERNATE.

B. PLANTS ARMED WITH SPINES.

Leaves with 3 or more coarse longitudinal veins, these conspicuous up to the apex
and meeting there; flowers in umbels. Fruit a small black berry; vines.
Smilax (p. 124).
Leaves with a midvein, or sometimes palmately veined, the lateral veins not promi-
nently continued to the apex and not meeting the midvein there; flowers never
in umbels.
Leaves entire.

Blades of the leaves ovate, thin; flowers dioecious, green, the staminate in ra-
cemes, the pistillate in dense heads; fruit a spheric syncarp 7-10 cm. in
diameter...... ee Toxylon (p. 141).

Blades of the leaves lanceolate or spatulate, fleshy; flowers perfect, greenish
purple, solitary or clustered in the axils; fruit a small red berry.

Lycium (p. 247).
Leaves toothed or lobed.
Spines short, usually less than 1 cm. long; flowers small, the petals greenish

yellow; fruit a many-seeded, very juicy berry; shrubs.
Grossularia (p. 172).

Spines long, usually over 1 cm. long; flowers large, the petals white; fruit a few-
seeded fleshy pome; shrubs or trees. ....-------------+-- Crataegus (p. 178).

24 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

BB. PLANTS WITHOUT SPINES.
C. LEAVES ENTIRE.

Blades of the leaves cordate at the base, about as broad as long; fruit a legume.
Flowers red-purple, appearing before the leaves................ Cercis (p. 180).
Blades of the leaves never cordate at the base, conspicuously longer than broad;
fruit not a legume.
Leaves bristle-pointed, at least when young; staminate flowers in catkins; fruit an
BCOM... 2-2-2. e reece ce eee eee eee ec eee ec ee ec ee eceeeee Quercus (p. 138).
Leaves not bristle-pointed; flowers usually not in catkins; fruit not an acorn.
Stipules present, sometimes deciduous in age but always present on young
branches or about the buds.
Leaves thick and leathery, obtuse; flowers perfect, large, white, solitary.

fruit large, woody, conelike..........2....2..--00--0- Magnolia (p. 161);
Leaves thin, acute; flowers dioecious, green, in catkins; fruit a very small
cc Salix (p. 132).

Stipules none.
Leaves gland-dotted beneath.
Flowers appearing before the leaves, yellow; plants with a spicelike odor;

fruit usually red, I-seeded.....................2-0-5. Benzoin (p. 162).
Flowers appearing after the leaves, white or pinkish white; plants without a
marked odor; fruit black, 10-seeded.............. Gaylussacia (p. 224),

Leaves not gland-dotted. *
Leaves evergreen, thick and leathery. Flowers showy, pink or red; fruit a
capsule... ..........2222ee. bebe ceceeeeeeeeeeee ERICACEAE (p, 222).
Leaves deciduous, comparatively thin.

Leaves large, 15-30 cm. long, obovate; fruit large (7-13 cm. long), pulpy,
yellowish. Shrubs or small trees, the young parts covered with a
rusty pubescence; flowers dark purplish brown or greenish, appearing
before the leaves................0.0.0.0-0--0-0002 Asimina (p. 161).

Leaves (except on young shoots or suckers) smaller, less than 15 cm. long;
fruits various, but never more than 2 or 3 cm. long.

Plants trees; flowers dioecious or polygamo-dioecious.
Fruit ovoid, 1-seeded, black; flowers few or numerous, on slender
peduncles. ..........0...00020.00000.2.22 2 eee Nyssa (p. 220).
Fruit depressed-globose, several-seeded, yellowish; flowers solitary or
few, on short stout peduncles or nearly sessile. .Diospyros (p. 227).
Plants shrubs; flowers perfect.

Leaves fleshy; branches usually recurved to the ground. Flowers
greenish purple; fruit a red berry.............. Lycium (p. 247).

Leaves thin, not fleshy; branches erect or spreading.

Fruit a dry capsule. Flowers white or pinkish.
ERICACEAE (p. 222).
Fruit a fleshy or juicy berry or drupe.
Flowers without a corolla, appearing before the leaves, the calyx
corolla-like, yellow; fruit l-seeded........... Direa (p. 211).
Flowers with a white or pinkish gamopetalous corolla, usually
appearing with or after the leaves; fruit 2-many-seeded.
Fruit 2-seeded; flowers in flat-topped cymes; leaves with numer-
ous conspicuous lateral veins.............. Cornus (p. 220).
Fruit several or many-seeded; flowers clustered or in racemes;
leaves with few and inconspicuous lateral veins.

Vaccinium (p. 224.)

FLORA OF THE DISTRICT OF COLUMBIA. 25

CC. LEAVES TOOTHED OR LOBED.
Plants climbing.
Leaves peltate, the petiole attached on the under side near the base; fruit juicy,
l-seeded. Tendrils none; leaf blades about as broad as long.
MENISPERMACEAE (p. 161).
Leaves not peltate; fruit with more than 1 seed.
Blades of the leaves acute or tapering at the base, not lobed; tendrils none; fruit

a dehiscent capsule.........-.-.-------- 22s eee eee eee Celastrus (p. 199).
Blades of the leaves cordate or truncate at the base, usually lobed; plants with
tendrils; fruit a juicy berry...........----.----++- ....- VITACEAE (p. 201).

Plants not climbing.
Fruit an acorn. Trees; staminate flowers in catkins. .........-.- Quercus (p. 138).

Fruit not an acorn.
Leaves with 2 acute lobes at the apex and with a lobe on each side near the base,
not toothed, glabrous. Fruit conelike; flowers very large, yellow.
Liriodendron (p. 161).
Leaves not 2-lobed at the apex, although often lobed in other ways........ D, DD.

D. BLADES OF THE LEAVES, AT LEAST SOME OF THEM, LOBED.

Branches with sharp winglike corky ridges. Flowers and fruits sessile in globose
heads; leaves glabrous, deeply lobed, the lobes acute...-.. Liquidambar (p. 173).

Branches not with winglike corky ridges.

Leaves usually 3-lobed, not at all toothed. Trees or shrubs with aromatic leaves;
fruit a blue fleshy drupe; flowers greenish yellow, appearing with the leaves.
Sassafras (p. 162).
Leaves toothed as well as lobed.

Blades of the leaves as long as broad or longer, pinnately many-lobed; fruit a
small nut coated with resinous grains. Shrubs with aromatic leaves and large
stipules... 22.2.2... 222-2 eee eee eee eee eee eens Comptonia (p. 135).

Blades of the leaves less than twice as long as broad, not pinnately many-lobed;
fruit not a small nut with resinous grains.

Flowers sessile in very dense spheric heads.
Leaves longer than broad, usually with 3 broad lobes; bark not peeling off

in plates.........22. 2.22 e cence eee eee ee eee eee eee es Papyrius (p. 141).
Leaves as broad as long, with more than 3 very acute lobes; bark peeling off
in plates. .....2.. 22222 cee eee eee eee eee eee ee eee Platanus (p. 173).

Flowers not in heads.
Flowers in catkins. Fruit a capsule, a nut, or a fleshy mutiple fruit.
Plants shrubs; fruit a nut; leaves very shallowly lobed. ..Corylus (p. 137).
Plants trees; fruit not a nut; leaves deeply lobed.
Fruit a capsule, the seeds hairy; leaves not rough-hairy.
Populus (p. 134).
Fruit a juicy multiple fruit, the seeds not hairy; leaves rough-hairy.
MORACEAE (p. 141).
Flowers never in catkins.
Bark peeling off in shreds; fruit of 2 dry follicles. Flowers white; shrubs.
Opulaster (p. 173).
Bark not peeling off in shreds; fruit a capsule or juicy.
Corolla large, 5-10 cm. broad; fruit a capsule. Leaves glabrous; shrubs.
Hibiscus (p. 203).
Corolla smaller, less than 4 cm. broad; fruit juicy.
Plants shrubs; flowers in racemes; fruit a spheric berry.
Ribes (p. 172).
Plants trees; flowers in corymbs; fruit a pome.....-.-- Malus (p. 177).

26 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

DD. BLADES OF THE LEAVES NOT LOBED, THE TEETH ALL EQUAL OR NEARLY SO.

Leaf blades very asymmetric at the base. .
Teeth of the leaves obtuse; fruit a woody capsule; flowers appearing in autumn,
bright yellow; shrubs...........2.......0..22.-0.--2.-.. Hamamelis (p. 172).

Teeth of the leaves acute; fruit not a woody capsule; flowers appearing in spring or
summer; trees or rarely shrubs.

Leaves glabrous or nearly so, not rough; flowers appearing after the leaves, their
peduncles united with a leaflike bract. Fruit small, indehiscent.

TILIACEAE (p. 202).

Leaves very pubescent or rough; flowers appearing with or before the leaves, their

peduncles never united with a leaflike bract.
Flowers in catkins; fruits arranged in a hoplike strobile....... Ostrya (p. 137).
Flowers not in catkins; fruits not in strobiles, either a small winged samara or a
drupe... 2.2... eee cee cece ee. ULMACEAE (p. 140).
Leaf blades symmetric at the base or nearly so,
Leaves evergreen, leathery; plants usually less than 30 cm. high. Flowers with a
corolla.

Fruit a dry capsule; teeth of the leaves not bristle-tipped; flowers in a terminal
long-stalked cluster; petals distinct................... Chimaphila (p. 221).

Fruit a fleshy capsule; teeth of the leaves bristle-tipped; flowers‘axillary, solitary;
petals united...........2000.00000.0..00.......--222... Gaultheria (p. 222),

Leaves not evergreen, or, if so, (in Ilex) the plants large shrubs or trees; plants
usually much more than 30 em. high.
Flowers all or mostly in catkins; fruit dry or, if fleshy, a cylindrical multiple fruit
(mulberry), never a capsule, sometimes a nut inclosed in a spiny or rough
bur; flowers appearing with or before the leaves; corolla none.
Fruit a nut inclosed in a spiny or warty bur. Trees or shrubs; teeth of the
leaves often bristle-tipped....................... FAGACEAE (p. 137).
Fruit not a nut inclosed in a spiny or warty bur.
Leaves aromatic, conspicuously gland-dotted; fruit a small spheric nut cov-
ered with white wax. Leaves oblanceolate; shrubs.

Myrica (p. 135),

Leaves not aromatic and gland-dotted; fruit not wax-covered.,
Fruit a small capsule; seeds long-hairy. Trees or shrubs, often with large

stipules..... 2.22.0... 2 00. elec eee ee ee ee SALICACEAE (p. 132).
Fruit not a capsule; seeds not hairy.

Fruit juicy or in spheric heads.................. MORACEAE (p. 141).

Fruit dry, never in spheric heads............. BETULACEAE (p. 136).

Flowers not in catkins; fruit often a capsule, never a nut or a multiple fruit;
flowers mostly appearing after the leaves ; corolla present,
Flowers sessile in dense heads on a common receptacle surrounded by an invo-
lucre of bracts; fruit an achene, bearing at the top a row of bristles, Corolla
gamopetalous; shrubs......................-------... Baccharis (p. 283).

ERICACEAE (p. 222),
Corolla of distinct petals: fruit not a depressed 5-lobed capsule.

Flowers solitary or clustered in the axils, Fruit a berry-like 4—-8-seeded
drupe; trees or shrubs; leaves sometimes persistent and with spiny teeth.
AQUIFOLIACEAE (p. 199).

FLORA OF THE DISTRICT OF COLUMBIA. 27

Flowers in terminal racemes, panicles, umbels, or corymbs.
Inflorescence a small dense panicle or corymb. Fruit dry, a capsule or
of several follicles; petals white or pink;.low shrubs.
Stipules present; leaves not 3-nerved; fruit of several follicles.
Spiraea (p. 174).
Stipules none; leaves 3-nerved; fruit a 3-celled capsule.
RHAMNACEAE (p. 201).
Inflorescence of racemes or of loose umbels.
Leaves broadest above the middle, wedge-shaped at the base. Shrubs;
fruit a 3-valved capsule.....---..----- CLETHRACEAE (p. 220).
Leaves broadest at or below the middle, not wedge-shaped at the base.
Fruit a dry capsule, 2-lobed at the apex; petals about 5 mm. long;
flowers in dense 1-sided racemes; shrubs
ESCALLONIACEAE (p. 172).
Fruit fleshy; petals usually more than 5 mm. long; flowers not in
1-sided racemes; shrubs or trees.
Fruit 1-seeded, sometimes pubescent, the calyx borne at its base

and deciduous........--------- AMYGDALACEAE (p. 179).
Fruit with more than 1 seed, glabrous, the calyx lobes present on its
SUMMIt... 22. eee eee eee eee eee MALACEAE (p. 177).

Il. Herbaceous Plants.

Key TO THE GROUPS.

Plants grasses or grasslike. Corolla green or non@....--.+-+-++++++se2e2 705° A (p. 28).
Plants not grasslike.
Plants floating on or submerged in water......--------+-----ererrrreee B (p. 28).

Plants not floating on or submerged in water, sometimes growing in the edge of
water but then usually erect.
Leaves compound, composed of few or many leaflets, or lobed to the midrib

base.
Stems climbing or twining, sometimes furnished with tendrils; plants green.
D (p. 31).
Stems not climbing or twining, or, if so, without green coloring, never fur-
nished with tendrils.
Plants without green coloring. Fruit a capsule; leaves reduced to scales.
E (p. 31).
Plants with green coloring.
Plants without a leafy stem, or the stems underground, the flowering
stems naked or bearing a single leaf or a whorl of leaves subtending
the inflorescence......-..---+----- ee ee cece terete F (p. 32).
Plants with leafy stems, the leaves sometimes reduced to scales; stems
sometimes bearing only a single leaf, but this borne far below the

inflorescence.
Leaves evidently parallel-veined; parts of the flower in 3’s or 6’s; plants
sometimes with bulbs.........-------e--- eset e rere G (p. 33).

Leaves net-veined; parts of the flower usually in 4’s or 5’s, but rarely
in 3’s; plants never with bulbs.
Leaves all, or at least some of them, opposite.
Leaves entire.....---------e eee eee erent errr H (p. 34).
Leaves toothed or lobed.......-.---------- eee rrerrre I (p. 36).

28 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Leaves alternate. *

Flowers sessile in dense heads on a common receptacle surrounded
by an involucre of bracts. Corolla always present, of united
petals, usually colored and often showy; fruit an achene or
rarely of 2 dry adherent carpels...................... J (p. 37).

Flowers not sessile in dense heads on a common receptacle sub-
tended by ar involucre of bracts,

Leaves entire (sometimes cordate at the base).......... K (p. 38).
Leaves toothed or lobed...........0..2..-.0--00000 eee L (p. 39).
A.

Grasses or grasslike plants.

Flowers not inclosed by husklike scales, composed of 3 sepals and 3 petals; stems

terete, usually simple, hollow or solid; fruit a dehiscent capsule containing few

or many seeds ....... 2.2.2.2. 0 2c e eee JUNCACEAE (p. 117).

Flowers inclosed by husklike scales, without a proper calyx or corolla; stems some-

times branched; fruit indehiscent, 1-seeded.

Leaves in 2 ranks on the stems; stems round or somewhat flattened, usually hollow;
leaf sheaths usually split; flowers with 2 bracts, one below and one above.

; POACEAE (p. 66).

Leaves in 3 ranks on the stems; stems round or usually 3-angled; leaf sheaths not

split; flowers with only one bract, this below....... CYPERACEAE (p. 92).

B.
Plants floating on or submerged in water.

Plants very small, less than 1 cm, long, floating free, consisting of a frond bearing 1
or 2 minute flowers on the upper surface, often with 1 or more roots beneath.
LEMNACEAE (p, 114).
Plants larger, several centimeters long or very large, with conspicuous leaves and
usually with branched stems.
Leaves entire or finely toothed, never lobed, sometimes deeply cordate at the base.
Blades of the leaves deeply cordate at the base, or peltate (the petiole attached
to the middle of the blade).
Leaves peltate, rounded, rarely more than 4 cm. wide; corolla of united petals,
not more than 3 mm. long; flowers clustered ........ -Hydrocotyle (p. 219).
Leaves not peltate, or, ifso, oval and usually much more than 4 cm. in diameter;
corolla of distinct petals, much more than 3mm. long; flowers not clustered.
NYMPHAEACEAE (p. 155).
Blades of the leaves not cordate at the base, never peltate.
Leaf blades spatulate in the floating leaves. Flowers minute, solitary or 2 or 3
together in the axils of the leaves, sessile; fruit nutlike, 4-lobed,

CALLITRICHACEAE (p. 197).
Leaf blades never spatulate.

Plants acaulescent. Leaves long, linear; fertile flowers borne on long, very

slender scapes; fruit indehiscent, many-seeded.... Vallisneria (p. 66).
Plants with stems.
Leaves alternate.

Stipules present; flowers in spikes, green; leaves linear or broad; fruit

l-seeded..........2200200.2.222. POTAMOGETONACEAE (p. 62).
Stipules wanting; flowers solitary on the end ofa long slender peduncle,
yellow; leaves linear; fruit many-seeded ....Heteranthera (p. 116).

Leaves opposite or whorled. Flowers minute, green.
Flowers with a 3 or 6-parted perianth; leaves finely toothed; fruit
several-seeded....... 2.2.0.0... 00. e cece eee eee Anacharis (p. 66).
Flowers without a perianth; leaves entire or finely toothed; fruit 1-seeded.
NAIADACEAE (p. 64).

FLORA OF THE DISTRICT OF COLUMBIA. 29

Leaves, at least most of them, deeply lobed or divided.
Blades of the leaves furnished with small bladders, finely dissected; flowers
yellow ....... 2.2.2.0. eee ee eee eee eee eee ..-..-PINGUICULACEAE (p. 255).
Blades of the leaves without bladders; flowers green or white.
Flowers conspicuous, with white petals, solitary on long slender pedicels.
Cabomba (p. 155).
Flowers minute, green, sessile or nearly so.
Flowers in spikes; blades of the upper leaves merely toothed or lobed;
fruit nutlike, 4-lobed .................- HALORAGIDACEAE (p. 214).
Flowers not in spikes; blades of all the leaves dissected; fruit not 4-lobed.
Leaves less than 1 cm. long, soft; fruit 1-seeded.
CERATOPHYLLACEAE (p. 155).
Leaves usually much more than 1 cm. long, rigid; fruit many-seeded.
PODOSTEMACEAE (p. 171).

Cc.

Leaves compound, of 2 or more leaflets.

Plants without leafy stems, the leaves all at the base, the flowering stems naked.
Leaflets 2; fruit a capsule, opening by alid. Juice colored; flowers white.
Jeffersonia (p. 160).
Leaflets 3 or more; fruit not opening by a lid.
Flowers apparently solitary, each ‘‘flower” really consisting of a spike of small
flowers surrounded by a corolla-like spathe; fruita berry. Leaflets acute.
Arisaema (p. 113).
Flowers in racemes or umbels; fruit a capsule.
Leaflets 3, entire, notched at the apex; flowers in umbels, regular. .
Ionoxalis (p. 191).
Leaflets more than 3, much divided into narrow lobes; flowers in racemes, very
irregular.......... 0.00.22 eee eee eee eee teen eens Bikukulla (p. 163).
Plants with leafy stems.
Corolla papilionaceous (shaped like that of a bean or pea); fruit a legume. Leaves
alternate, with stipules...............2.....-2eeeeeee ees FABACEAE (p. 181).
Corolla not papilionaceous; fruit not a legume (except in Caesalpiniaceae).
Flowers borne in a dense head on a common receptacle surrounded by an involucre
of bracts (the head often taken to be a single flower). Fruit an achene;
stipules none; corolla gamopetalous.
Plants with milky juice; leaflets 3; corollas all irregular..Prenanthes (p. 265).
Plants with colorless juice; leaflets usually more than 3; corollas regular, or the
outer ones irregular.
Pistillate and staminate flowers in separate heads, the involucres of the fertile

heads hard and woody, spiny......-.-----------+e+- Ambrosia (p. 268).
Pistillate and staminate flowers in the same head, or the flowers all perfect,
the involucres never hard or spiny.........-.- ASTERACEAE (p. 268).

Flowers not borne in a dense head on a common receptacle surrounded by an
involucre of bracts.
Stems bearing only a single leaf or a pair or whorl of leaves.

Sepals and petals each 4; fruit a long narrow dry pod. Leaflets 3 or 5.
Dentaria (p. 169).
Sepals 5 or more; petals 5 or more or united or wanting; fruit juicy or of few

or many achenes in a head.
Fruit a head of achenes; corolla none, but the sepals petal-like.

RANUNCULACEAE (p. 156).

30 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Fruit a juicy drupe or the seeds with a fleshy coat; corolla present.
Leaflets 2 or 3-lobed, numerous; flowers in racemes or panicles; petals

distinct......... cece cence cece cence ee eeeeeee Caulophyllum (p. 161).
Leaflets with numerous teeth, few or many; flowers in umbels; petals
TT ARALIACEAE (p. 215).

Stems bearing normally 2 or more alternate leaves or 2 or more pairs of leaves.
Leaves all or mostly opposite.
Leaves of 5-7 digitate leaflets. Flowers very small, green; fruit an achene.
Cannabis (p. 142).
Leaves pinnate or pinnately lobed.
Flowers blue or white. Fruit a capsule.
HYDROPHYLLACEAE (p. 236).
Flowers yellow or pink.
Plants erect; flowers yellow; fruit a many-seeded capsule.
Aureolaria (p. 253).
Plants with long slender trailing branches; flowers pink; fruit 1-seeded,
indehiscent............-..------5 cece ee eeeeee Valeriana (p. 261).
Leaves alternate.
Stems climbing. Flowers blue or purple; leaves pinnate; fruit red berry.
Solanum (p. 248).
Stems not climbing.
Corolla of united petals, blue or white. Leaves pinnate or pinnately
lobed; fruit a capsule.
Leaflets entire; style 1...............0...2202. Polemonium (p. 235).
Leaflets toothed or lobed; styles 2... HYDROPHYLLACEAE (p. 236).
Corolla of distinct or nearly distinct petals, or wanting.
Corolla very irregular, yellow or pink, some of the petals spurred.
Glabrous annuals; fruit dry; leaflets many.

FUMARIACEAE (p. 163).
Corolla regular,

Leaflets (3) obcordate, entire, notched at the apex. Flowers yellow,
in cymes; fruit a capsule.................. Xanthoxalis (p. 191).
Leaflets not obcordate and entire.
Leaves with 5-7 palmate equal leaflets. Plants viscid-pubescent;
petals 4, white or pink; fruit a long narrow pod.
CAPPARIDACEAE (p. 170).
Leaves not with 5-7 palmate equal leaflets............... A, AA,

A. LEAVES WITH STIPULES.

Flowers pink, the 5 petals small, Plants annual, pubescent; leaflets numerous;
fruit dry..... 22.2.2. eee eee cee eee cece ee cece eee eee Erodium (p. 190).
Flowers yellow or white.
Leaflets entire, 10 or more; flowers yellow; fruit a legume.
CAESALPINIACEAE (p. 180).
Leaflets toothed or lobed, often only 3; flowers yellow or white; fruit not a legume.

ROSACEAE (p. 173).
AA. LEAVES WITHOUT STIPULES.

Petals and sepals each 3. Flowers minute, axillary; annual plants of wet soil, with
pinnate leaves................2..2.20020200 2 eee LIMNANTHACEAE (p. 198).
Petals and sepals 4 or more or wanting, the sepals often united, sornetimes only 2.
Flowers in regular umbels, small, yellow or white; fruit of 2 dry adherent carpels.
Calyx entire or 5-toothed.................2.0.22--0--- APIACEAE (p. 215).
Flowers not in umbels; fruit not of 2 dry adherent carpels.
Sepals 2, falling as the flower opens; plants with white or yellow juice, pubescent.
Flowers yellow or red; fruit a capsule......... PAPAVERACEAE (p. 162).

FLORA OF THE DISTRICT OF COLUMBIA. 31

Sepals more than 2, usually persistent; plants with colorless juice.
Petals and sepals each 4, regular; petals yellow, white, or pink; fruit a 2-celled
pod with several or numerous seeds. Leaves once pinnate.
BRASSICACEAE (p. 163).
Petals 5 or none; sepals usually 5, sometimes 4; petals yellow, red, or white;
sepals and petals sometimes spurred; fruit a 1-seeded achene, or each fruit
composed of several pods.........-......-- RANUNCULACEAE (p. 156).

Plants climbing, often with tendrils; leaves simple.

Plants with tendrils.

Leaves 5~9-ribbed, usually entire; flowers in umbels. Fruit a bluish black berry
with 2-6 seeds; stipules none...........----------- SMILACACEAE (p. 124).

Leaves not ribbed, lobed or toothed; flowers not in umbels.

Stipules present; petals distinct; flowers 2.5-5 cm. broad, solitary, greenish yellow.
PASSIFLORACEAE (p. 211).
Stipules none; petals united; flowers about 1 cm. broad, mostly in racemes or
COTYMDS... 2... ee eee eee eee ee ee eee eee eee eee CUCURBITACEAE (p. 262).

Plants without tendrils.

Leaves peltate, the petiole attached on the under side of the blade near the margin;
the blades angled or lobed; fruit juicy, l-seeded. Flowers very small, in axil-
lary panicles........-...-...--------ee ee eee MENISPERMACEAE (p. 161).

Leaves not peltate; fruit not juicy.

Leaves, at least the lowest ones, opposite or whorled.
Leaves entire; fruit not an achene, with 3 or many seeds.
Plants with milky juice; petals 5, united, whitish or dark purple; fruit of
large pods, containing many seeds, these bearing a tuft of silky hairs.
ASCLEPIADACEAE (p. 231).
Plants with colorless juice; petals 3, distinct, greenish yellow; fruit a 3-winged
capsule, the seeds not hairy.............. DIOSCOREACEAE (p. 125).
Leaves toothed or lobed; fruit an achene.
Blades of the leaves, at least most of them, deeply lobed, rough; flowers dioe-

cious, green, in catkins or panicles...................Humulus (p. 142).
Blades of the leaves merely toothed, glabrous; flowers perfect, in small heads,
each head surrounded by 4 bracts..................-. Mikania (p. 275).

Leaves alternate.
Leaves with sheathing stipules; corolla none; fruit an achene.
POLYGONACEAE (p. 144).
Leaves without stipules; corolla gamopetalous, showy; fruit a capsule.
CONVOLVULACEAE (p. 233).

E.

Plants without green coloring; leaves reduced to scales; fruit a capsule.

Stems twining, parasitic upon the stems of other plants, bright yellow or orange, slender
Corolla regular, gamopetalous....-............---++-+ CUSCUTACEAE (p. 234).
Stems erect, the plants growing in the ground, not bright yellow or orange, stout.
Flowers regular or nearly so, the petals distinct. Plants glabrous or pubescent.
MONOTROPACEAE (p. 221).
Flowers very irregular.
Plants glabrous; petals and sepals each 3, distinct...... ORCHIDACEAE (p. 127).
Plants pubescent; corolla of united petals........ OROBANCHACEAE (p. 254).

32 CONTRIBUTIONS FROM THii NATIONAL HERBARIUM.

F.

Plants with simple leaves, acaulescent or the stems underground, the flowering
stems naked or bearing a single leaf or whorl of leaves subtending the inflorescence.

Leaves pitcher-like or covered with long gland-bearing hairs, purplish. Flowers reg-
ular, with 5 petals; fruit a capsule.
Leaves pitcher-like; flowers solitary on long scapes..SARRACENIACEAE (p. 170).
Leaves flat, covered with gland-bearing hairs; flowers in racemes.
DROSERACEAE (p. 170).
Leaves neither pitcher-like nor covered with gland-bearing hairs.
Flowers sessile in dense heads or spikes.
Flowers in heads.

Leaves toothed or lobed; flowers yellow.......... CICHORIACEAE (p. 263).
Leaves entire, narrow; flowers yellow or white.
Leaves 2-ranked; flowers yellow...............2.-.. XYRIDACEAE (p. 115),
Leaves not 2-ranked; flowers whitish......... ERIOCAULACEAE (p. 115).
Flowers in spikes.
Spikes twisted; leaves often wanting; flowers white......... Ibidium (p. 130),

Spikes not twisted; leaves always present; flowers not white.
Leaves deeply cordate at the base, broad, not ribbed, glabrous; flowers blue,
showy; fruit l-seeded.......2.2..2.......20.2.000. Pontederia (p. 116).
Leaves slightly or not at all cordate, broad and ribbed or linear, often pubes-

cent; flowers small, greenish; fruit with 2 or more seeds.
PLANTAGINACEAE (p. 256).
Flowers not sessile in dense heads or spikes, sometimes in dense racemes, but then

pediceled.
Scapes with more than 1 flower.
Leaves terete, fleshy. Flowers pink; fruit a capsule........ Talinum (p. 150).

Leaves flat, not fleshy.
Corolla very irregular. Leaves parallel-veined..ORCHIDACEAE (p. 127).
Corolla regular.

Flowers or branches of the inflorescence forming several or many whorls;
fruit a head of numerous achenes. Petals 3, white; leaves usually
cordate or hastate.........-...........2..220. ALISMACEAE (p. 64).

Flowers not whorled; fruit a capsule.

Leaves evidently parallel-veined, linear or very narrow; petals 3.
Leaves 2-ranked. Flowers usually blue....... IRIDACEAE (p. 126).
Leaves not 2-ranked.

Flowers 4 or fewer, yellow or white; leaves sometimes pubescent.
AMARYLLIDACEAE (p. 125).
Flowers numerous, or, if few, orange; leaves glabrous.
LILIACEAE (p. 120).

Leaves net-veined, oblong to rounded; petals or corolla lobes 5.

Blades of the leaves very pubescent, conspicuously toothed; flowers
in cymes, white, the petals distinct; capsule cleft nearly to the
base. ...2 222 e eee cee eee ee eee eee Saxifraga (p. 172).

Blades of the leaves glabrous, entire or very shallowly toothed; flowers
not in cymes; capsule not cleft.

Flowers in umbels; corolla gamopetalous, reflexed, rose-colored.

leaves not evergreen .............0. 20024 Dodecatheon (p. 227).
Flowers in racemes; petals distinct, white, greenish, or pink, spread-
ing; leaves evergreen.................. PYROLACEAE (p. 220).

Scapes 1-flowered.
Leaves toothed or lobed. Petals distinct or none.
Fruit a head of achenes; leaves 3-lobed, the lobes entire or merely crenate;
flowers yellow, bluish, or white; petals sometimes wanting, the sepals
then petal-like................ seeeeee- RANUNCULACEAE (p. 156).

FLORA OF THE DISTRICT OF COLUMBIA. 33

Fruit a capsule; leaves toothed or with toothed lobes; flowers blue or white;
petals present.
Juice orange; leaves thick and succulent; petals regular, white; capsule

ACUTE. 2. eee ee eee ec e cece cee eee eee eee ee cere Sanguinaria (p. 162).
Juice colorless; leaves thin; petals irregular, blue or white; capsule
Obtuse... 22... - cece eee eee eee cee eee eee eee eee eeeee Viola (p. 206).

Leaves entire, sometimes cordate at the base.
Blades of the leaves broadly kidney-shaped, as broad as long or broader.
Fruit a capsule.

Leaves pubescent; flowers brownish purple; plants of woodlands.

Asarum (p. 143),

Leaves glabrous; flowers blue or white; plants of muddy shores.

Heteranthera (p. 116).
Blades of the leaves not kidney-shaped, longer than broad, usually narrow
but sometimes oval or triangular.

Flowers crowded in a spike, this surrounded by a corolla-like spathe, the
whole inflorescence appearing like a single flower; fruit a berry,
fleshy, with 1 or few seeds. ............--0-00-05- ARACEAE (p. 113).

Flowers not crowded in a spike surrounded by a spathe; fruit a capsule, or
fleshy and with numerous seeds.

‘Leaves deeply cordate, more than 15 cm. wide; fruit fleshy. Flowers
yellow... 2.0.02. cee eee eee ee eee e eee eee Nymphaea (p. 155).
Leaves not cordate, less than 10 cm. wide; fruit a dry capsule.
Flowers very irregular; leaves sometimes ovate or oval.

ORCHIDACEAE (p. 127).
Flowers regular; leaves narrow.

Leaves 2-ranked; flowers blue............-.-- IRIDACEAE (p. 126).
Leaves not 2-ranked; flowers white or yellow.
Erythronium (p. 122).

G.

Green plants with leafy stems, the leaves rarely reduced to scales, the stems some-
times bearing only a single leaf or pair of leaves, but this borne far below the inflo-
rescence; leaves evidently parallel-veined; parts of the flower in 3’s or 6’s.

Flowers sessile in very dense heads or spikes, without a perianth, or the perianth
represented by 3 or 6 minute green scales. Plants growing in or at the edge of
water; leaves linear.

Flowers in long, brown or green spikes: plants about a meter high.
TYPHACEAE (p. 62).
Flowers in green spheric heads; plants rarely half a meter high.
SPARGANIACEAE (p. 62).
Flowers not sessile in dense spikes or heads; perianth present, usually conspicuously
colored.
Petals irregular; flowers sometimes inclused in a spathe. Fruit a capsule.
Flowers blue, inclosed inaspathe; stems much jointed; leaves ovate or lanceolate.
Commelina (p. 116).
Flowers never blue, not inclosed in a spathe; stems not jointed

ORCHIDACEAE (p. 127).
Petals regular; flowers not inclosed in a spathe.

Leaves 2-ranked; fruit a capsule.
Flowers in racemes, whitish, very small; inflorescence glandular-pubescent.
Tofieldia (p. 119).
Flowers not in racemes, usually blue or orange and large; plants without
glandular pubescence.......----+----+++e0es+eeeeee IRIDACEAE (p. 126).

69289—19——3

34 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Leaves not 2-ranked; fruit a capsule or a berry.
Flowers blue or purple. Leaves linear; fruit a capsule..Tradescantia (p. 116).
Flowers not blue or purple.
Fruit a berry; plants never with bulbs; leaves sometimes a single whorl at
the top of the stem..................... CONVALLARIACEAE (p. 123).
Fruit a capsule; plants often with bulbs; leaves never a single whorl.
Style 1 and cleft to below the middle, or styles 3; stems sometimes
branched; flowers mostly small and greenish.
MELANTHIACEAE (p. 119).
Style 1, cleft only at the summit; stems simple up to the inflorescence;
flowers mostly large and brightly colored........ LILIACEAE (p. 120).

H.

Plants with leafy stems; leaves all or part of them opposite, the blades simple,
entire, net-veined.

Flowers sessile in dense heads on a common receptacle surrounded by an involucre

of bracts. Fruit an achene................00.000 2c c ee eee eeeee Group J (p. 37).
Flowers not sessile in dense heads on a common receptacle surrounded by an involucre
of bracts... 2.2... 2c eee ee ccc ccc e cee e cece cece ee nceenseeeees A, AA.

)

A. COROLLA GAMOPETALOUS (OF UNITED PETALS), ALWAYS PRESENT, CONSPICUOUS,
COLORED.

Corolla conspicuously irregular.
Fruit of 4 small nutlets in the bottom of the calyx; stems usually conspicuously
4-angled; leaves usually gland-dotted............... MENTHACEAE (p. 239).
Fruit a dehiscent capsule; stems usually not 4-angled; leaves not gland-dotted.
Capsules abruptly contracted at the base into a short stalk; flowers purplish, in
axillary clusters or spikes; seeds few, borne on hooks in the capsule.
ACANTHACEAE (p. 255).
‘Capsules not contracted at the base; flowers blue, white, pink, or purplish,
racemose or axillary and then usually solitary; seeds often numerous, not
borne on hooks.................20..200-- SCROPHULARIACEAE (p. 248).
Corolla regular or nearly so.
Leaves in whorls.
Leaves gland-dotted; corolla bright yellow; fruit a glabrous capsule with more

than 2 seeds......... 2. cece ce eee ee eee Lysimachia (p. 225).
Leaves not gland-dotted; corolla white or greenish, never bright yellow; fruit of
2 1-seeded indehiscent united nutlets, often hairy......... Galium (p. 257).

Leaves not in whorls.
Leaves with stipules, or the petioles connected by a stipular membrane.
Calyx united with the ovary and capsule; flowers never red.
RUBIACEAE (p. 257).
Calyx free from the capsule; flowers red or white.... LOGANIACEAE (p. 228).
Leaves without stipules.
Ovaries 2, each or only one developing into a large pod, this usually 5 cm. long
or more. Seeds usually with a tuft of down; juice usually milky.
Flowers solitary or in cymes; corolla bell-shaped and shallowly lobed or
funnelform, white, pink, or blue; pods slender, rarely over 6 mm. in
in diameter, glabrous, smooth. Leaves sometimes evergreen.
APOCYNACEAE (p. 229).
Flowers in umbels; corolla neither bell-shaped and shallowly lobed nor
funnelform, never blue; pods stout, usually more than 6 mm. in diameter,
often pubescent or tuberculate........... ASCLEPIADACEAE (p. 231).

FLORA OF THE DISTRICT OF COLUMBIA. 35

Ovary 1; fruit a single capsule or drupe.
Corolla about as long as the calyx; fruit indehiscent, 3-seeded, purplish or
yellowish; leaves often clasping the stem........... Triosteum (p. 260).
Corolla much longer than the calyx; fruit dehiscent, not colored, usually
with more than 3 seeds; leaves not clasping.
Capsule abruptly contracted at the base; seeds on hooks inside the capsule;
stamens fewer than the corolla lobes. Flowers bluish or purplish.
Ruellia (p. 256).
Capsule not contracted at the base; seeds not on hooks; stamens as many
as the corolla lobes.
Stamens opposite the corolla lobes; flowers bright yellow or else solitary
in the axils, Corolla tube none or scarcely any.
PRIMULACEAE (p. 225).
Stamens alternate with the corolla lobes; flowers never bright yellow
nor solitary in the axils. .
Capsule 1-celled; seeds numerous; plants glabrous or nearly so; leaves
sometimes reduced to scales; corolla tube sometimes nearly obso-
lete, usually thick and stout......... GENTIANACEAE (p. 228).
Capsule 3-celled; seeds 3; plants usually pubescent; leaves never
reduced to scales; corolla tube long and slender... Phlox (p. 235).

AA. COROLLA OF DISTINCT PETALS OR WANTING (THE CALYX SOMETIMES COROLLA-LIKE),

Leaves dotted with black glands, usually sessile. Flowers yellow or pink; leaves
mostly sessile... ....... 2-2... e eee eee eee eee ee eee HYPERICACEAE (p. 204).
Leaves not dotted with black glands.
Leaves with stipules.
Leaves obovate; petals 2 or 3, evident; plants of very wet soil.
ELATINACEAE (p. 205).
Leaves linear; petals 5, or very minute or wanting; plants of dry soil.
Petals about 3 mm. long; pedicels glandular-pubescent.......-. Tissa (p. 151).
Petals minute or none; pedicels without glandular pubescence.

CORRIGIOLACEAE (p. 150).
Leaves without stipules.

Plants with milky juice; capsule deeply 3-lobed. Upper leaves usually whorled;
flowers small, white or greenish..........-...- EUPHORBIACEAE (p. 194).
Plants with colorless juice; fruit not 3-lobed.

Stems 1-flowered, the flowers solitary on long slender peduncles, nodding;
sepals 4, petal-like, thick and leathery, large (2.5 cm. long). Leaves sessile
or nearly so, silky beneath..................02..220- .--.Viorna (p. 160).
Stems usually with more than 1 flower, the flowers not solitary on long slender

peduncles, not nodding; sepals smaller, not thick and leathery.
Flowers in simple spikes or racemes, very irregular, the sepals 5, 3 of them
small, 2 of them large and colored like the 3 petals. Leaves often whorled;
fruit very flat...... wee e cece cece ee ee eee POLYGALACEAE (p. 193).

Flowers not in simple spikes or racemes, not irregular.
Leaves mostly whorled in 3’s, very fleshy, obovate; branches of the inflo-
rescence l-sided. Petals white......................- Sedum (p. 171).
Leaves not whorled, or, if so, the blades not fleshy; branches of the inflo-
rescence not very 1-sided.
Calyx and corolla wanting; fruit 4-lobed. Flowers solitary in the axils;
leaves obovate; small prostrate plants of wet soil.

CALLITRICHACEAE (p. 197),
Calyx and usually a corolla present; fruit not 4-lobed........... . B, BB.

36 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

B. SEPALS UNITED, AT LEAST BELOW, OFTEN NEARLY TO THE APEX.

Flowers surrounded by a calyx-like involucre, the calyx pink, corolla-like.
ALLIONIACEAE (p. 149).
Flowers not surrounded by an involucre; calyx green.
Flowers sessile in the forks of the branches, small, green. Leaves linear; plants
annual.........2.. 222.22. eee eee eee eens Scleranthus (p. 151).
Flowers not sessile in the forks of the branches, usually large and colored.
Petals inserted on the throat of the calyx; flowers axillary or whorled.
LYTHRACEAE (p. 211).
Petals not inserted on the calyx; flowers mostly in cymes or panicles.
SILENACEAE (p. 153).
BB, SEPALS DISTINCT.

Leaves whorled; flowers axillary, pediceled. Plants annual..AIZOACEAE (p. 150).
Leaves not whorled; flowers usually not axillary.
Flowers (calyx and bracts) greenish white, crowded in short slender spikes arranged
in loose panicles; petals none. Leaves broadly ovate, petioled..Iresine (p. 149).
Flowers not as above; petals usually present, but sometimes falling early.
Sepals 2; siem leaves a single pair, Petals pink............ Claytonia (p. 150).
Sepals 5; stem leaves numerous.
Petals whi e or wanting; sepals equal or nearly so; stems usually soft and succu-
CS ALSINACEAE (p. 151).
Petals yellow, greenish, or purplish; sepals unequal, the 2 outer much narrower
than the 3 inner ones; stems rigid and almost woody.
CISTACEAE (p. 205).
I.

Plants with leafy stems; leaves opposite, the blades toothed or lobed, simple, net-
veined.

Flowers sessile in dense heads on a common receptacle surrounded by an involucre of
bracts.
Chaff of the receptacle (among the flowers) with long rigid spinelike tips; receptacle
several times as long as broad; stamens distinct. Leaves with prickly teeth.
DIPSACACEAE (p. 262).
Chaff of the receptacle not with long rigid spinelike tips, sometimes wanting;
receptacle usually less than twice as # long as broad; stamens united by their

anthers in @ ring... 2... cee ee eee eee Group J (p. 37).
Flowers not sessile in dense heads on a common receptacle surrounded by an involucre
of bracts.

Corolla gamopetalous (of united petals), usually colored and conspicuous.
Fruit composed of 2 or 4 nutlets in the bottom of the calyx, these sometimes
united at first but separating in age. Stems usually 4-sided.

Ovary not lobed, the style terminal upon it; plants not with a mintlike odor, the
leaves not gland-dotted; corolla usually nearly regular. Flowers sessile in
spikes or heads.........-...0..-02-ee eee eens .. VERBENACEAE (p. 239).

Ovary deeply 4-lobed, the style rising from between the lobes; plants usually
with a mintlike odor, the leaves usually gland-dotted; corolla usually very
irregular.......2... 202... 2222 e eee eee eee MENTHACEAE (p. 239).

Fruit not composed of 2 or 4 nutlets, the nutlets either only 1 or the fruit a capsule.

Flowers reflexed and appressed to the stem in fruit; fruit a single nutlet in the
bottom of the calyx; calyx teeth hooked at the tip. Corolla purplish;
leaves on slender petioles....................-- PHRYMACEAE (p. 256).

Flowers not reflexed and appressed in fruit; fruit not a nutlet in the bottom of
the calyx; calyx teeth not hooked at the tip.

FLORA OF THE DISTRICT OF COLUMBIA. 37

Calyx wholly united with the ovary and fruit; fruit indehiscent; stamens 3;
corolla nearly regular, white; plants annual, glabrous. Valerianella (p. 261).
Calyx free from the ovary and fruit; fruit a dehiscent capsule; stamens 2, 4,
or 5; corolla usually irregular, variously colored; plants annual or

perennial, usually pubescent...... SCROPHULARIACEAE (p. 248).
Corolla of distinct petals,or sometimes wanting. the flowers sometimes small and green.
Leaves deeply lobed.

Plants glabrous; leaves only 2, borne at the top of the stem; flower 1, borne
between the leaves, with large white petals; fruit juicy.

Podophyllum (p. 160).

Plants pubescent; leaves more than 2; flowers usually more than 1; fruit dry.

Petals present, the sepals green; fruit composed of 5 carpels; plants annual

or perennial.............02-0- eee e eee eee eee ees Geranium (p. 190);
Petals none, but the sepals colored and petal-like; fruit of numerous achenes;
plants perennial...................+++--- RANUNCULACEAE (p. 156).

Leaves only toothed, or rarely very shallowly lobed.
Plants with milky juice; fruit deeply 3-lobed. Corolla none, but the flowers
surrounded by an often corolla-likeinvolucre. EUPHORBIACEAE (p. 194);
Plants with colorless juice; fruit not 3-lobed.
Flowers green, without petals; fruit 1-seeded.
Plants covered with whitish scales, never with slender hairs nor glabrous.

flowers solitary or in spikes; stipules none.......... Atriplex (p. 148).
Plants glabrous or with slender, sometimes stinging hairs; flowers mostly
clustered; stipules present........-..------ URTICACEAE (p. 142).

Flowers with white or colored petals; fruit with more than one seed.
Petals large (1 cm. long or longer), pink or purplish; leaves 3-4-ribbed;

plants bristly-hairy.......-.-------- MELASTOMATACEAE (p. 212).
Petals small (much less than 1 cm. long); leaves not ribbed; plants not
bristly hairy.

Leaves about as broad as long; calyx free from the ovary and fruit;
petals white or yellow; plants flowering in spring; seeds never;
witha tuft of hairs and fruit never bristly. SAKIFRAGACEAE (p.171).

Leaves much longer than broad; calyx united with the ovary and fruit;
petals pink or whitish; plants flowering in summer or autumn;
seeds with a tuft of hairs or else the fruit covered with hooked bris-
tles..... 2.22. e eee eee ee ee eee eee ee ee eee ONAGRACEAE (p. 212).

Flowers sessile in dense heads on a common receptacle surrounded by an involucre
of bracts; corolla gamopetalous, regular or irregular; calyx represented by scales or
bristles or sometimes none; stamens united by their anthers in a ring; fruit an achene.
(These plan's are commonly called Composites. Typical of them are the sunflower,
goldenrod, as‘er, dandelion, and ragweed, The heads of flowers are often mistaken
by amateur botanists for a single flower.)

Plants with milky juice; corolla of all the flowers irregular, produced into a strap-
shaped ray; leaves alternate or sometimes all basal. ..CICHORIACEAE (p. 263),

Plants not with milky juice; corollas all regular, or the outer ones produced into a
strap-shaped ray; leaves alternate or opposite.

Flowers staminate and pistillate, the 2 kinds in separate unlike heads; involucre
of the pistillate heads woody, spiny; ray flowers none; flowers greenish or
yellowish. (Iagweeds and cockleburs)......-.- AMBROSIACEAE (p. 267).

Flowers all perfect, or both kinds in the same head, or rarely in separate heads,
but the heads-then all similar in general appearance; involucre not woody
and spiny; ray flowers usually present.........------ ASTERACEAE (p. 268).

38 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

K.

Plants with leafy stems; leaves alternate, the blades simple, entire, net-veined.

Stem leaves reduced to minute scales. Corolla very irregular, spurred; small slender

plants of very wet soil..............0........2.. PINGUICULACEAE (p. 255).
Stem jleaves not reduced to scales.

Leaves with stipules, these sometimes united into a sheath.
Stipules united and sheathing; fruit an achene. Petals none, the flowers small,
greenish, whitish, or pink, mostly axillary or in spikes.

POLYGONACEAE (p. 144).

Stipules not sheathing; fruit a capsule or a pod, with more than one seed.

Petals none; plants glabrous; fruit a small 3-celled capsule.

Phyllanthus (p. 195),

Petals present, yellow; plants pubescent; fruit an inflated 1-celled pod.

; Crotalaria (p. 183).
Leaves without stipules.

Corolla gamopetalous, usually colored and conspicuous.

Flowers 4-5 cm. long, white; calyx inclosed by 2 broad bracts. Leaves often
cordate at the base; fruit a capsule............... Convolvulus (p. 234).

Flowers less than 3 cm. long; calyx not inclosed by 2 broad bracts,
Juice milky; flowers in umbels; fruit of 1 or 2 large pods, the seeds with
tufts of hairs... 2.0.0.0... 2 eee eee cece c cence Acerates (p. 231),
Juice colorless; flowers not in umbels; fruit a small capsule or berry or of 4

nutlets, the seeds not with tufts of hairs.
Corolla spurred, yellow. Nearly glabrous, glaucous perennial.

Linaria (p. 250).
Corolla not spurred.

Fruit of 4 nutlets; plants rough-hairy, often bristly, or glabrous and with
blue flowers (the flowers sometimes white, yellow, or reddish).
BORAGINACEAE (p. 237)"
Fruit a capsule or a berry; plants never rough-hairy, not with blue
flowers,
Corolla white; fruit a capsule; calyx not enlarged in fruit.
PRIMULACEAE (p. 225).
Corolla yellow; fruit a berry, inclosed by the enlarged bladdery calyx.
Physalis (p. 247).
Corolla of distinct petals or wanting, the calyx sometimes colored and corolla-like.
Flowers with neither calyx nor corolla, crowded in long cylindrical dense
spikes; leaves cordate, petioled. Plants of marshy soil.
SAURURACEAE (p. 132).
Flowers with a calyx and often with a corolla; leaves not cordate, or, if so, the
flowers not in spikes,
Flowers green, small, the sepals never colored; petals none. Fruit dry or

nearly so.
Plants perennial, pubescent; fruit a capsule, with more than 1 seed. Leaves
small and narrow........ eee eee eee eee eee CISTACEAE (p. 205).

Plants annual, glabrous or pubescent; fruit an achene or a 1-seeded capsule.
Flowers all in loose cymose axillary clusters; style 1, not branched.
Plants pubescent................0..0cccc0e0-e eee Parietaria (p. 142).
kiowers all or most of them in spikes or terminal cymes or panicles, or
else all in dense sessile axillary clusters; styles 2 or 3, or 1 and
branched.
Flowers subtended by scarious bracts, the sepals awn-pointed; fruit
dehiscent or indehiscent; leaves never linear nor with spiny tips;
plants never white-mealy.......... AMARANTHACEAE (p. 148).

FLORA OF THE DISTRICT OF COLUMBIA. 39

Flowers not subtended by bracts, the sepals not awn-pointed; fruit
indehiscent; leaves linear and with spiny tips, or the plants white-
mealy, at least about the. inflorescence.

CHENOPODIACEAE (p. 147).

Flowers colored; petals present and colored, or the petals sometimes wanting
and the calyx colored and corolla-like.

Leaves deeply cordate and densely velvety-pubescent; fruit composed of

12-15 carpels arranged in a ring. Petals yellow.....Abutilon (p. 203).

Leaves not cordate, or, if so, not velvety-pubescent; fruit not of numerous
carpels.

Blades of the leaves very fleshy and succulent, obovate or terete; fruit a
many-seeded capsule opening by a lid. Petals present, bright-
colored... 2.2222. eee eee eee ee eee eee eee eeeeees Portulaca (p. 150).

Blades of the leaves thin, not fleshy; fruit not opening by a lid.

Flowers borne on the lower part of the stem near the ground; calyx
S-shaped. Petals none; leaves petioled, cordate or halberd-
shaped.........------ eee eee eee cece ree eeeee Aristolochia (p. 143).

Flowers borne on the upper part of the stem; calyx never curved.

Calyx united with the ovary and fruit, apparently borne on top of them.
Petals present, yellow or purplish; fruit dehiscent, with several or
many seeds; plants often pubescent, never glaucous.
ONAGRACEAE (p. 212).
Petals none, the calyx white and corolla-like; fruit indehiscent,
1-seeded; plants glabrous, glaucous. SANTALACEAE (p. 143).
Calyx free from the ovary and calyx, the ovary inside the calyx.
Petals none, the 5 sepals petal-like; fruit a juicy dark purple berry.
Flowers in racemes......-.--- PHYTOLACCACEAE (p. 150).
Petals present; fruit dry. ;
Sepals and petals each 5; flowers corymbed or panicled; fruit
5-celled, as broad as long; petals yellow or blue.
LINACEAE (p. 192).
Sepals and petals each 4; flowers in racemes; fruit 1 or 2-celled,
longer than broad; petals usually white, sometimes yellow.
BRASSICACEAE (p. 163).

L.
Plants with leafy stems; leaves alternate, the blades toothed or lobed, net-veined.

Leaves peltate (the petiole attached to the underside). Fruit of 2 small seedlike carpels.
Hydrocotyle (p. 219).
Leaves not peltate.
Fruit and ovary covered with hooked spines. Leaves deeply lobed; corolla minute,
greenish yellow. ...-.....-.-eeeeee cece cece eet e terete ness Sanicula (p. 217).
Fruit and ovary never with hooked spines, but rarely with straight ones.
Leaves conspicuously lobed.
Stems and leaves spiny. Sepals 5, united; fruit a smooth berry.
, Solanum (p. 248).
Stems and leaves not spiny.
Corolla of united petals. Fruit a capsule.
Flowers in spikes; corolla very irregular...........-. Pedicularis (p. 254).
Flowers not in spikes; corolla regular......H¥YDROPHYLLACEAE (p. 236).
Corolla of distinct petals, or none.

Calyx lobes 3; fruit sharply 3-angled, dry. Blades of the upper leaves
toothed, those of the lower ones deeply pinnate-lobed; plants uf very
wet situations, the sessile axillary flowers without petals.

Proserpinaca (p. 215).

40 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Calyx lobes or sepals more than 3; fruit not sharply angled.
Fruit 1-seeded, indehiscent; flowers small, green, with no corolla. Sepals
5, distinct, or united at the base; plants usually finely white-mealy.
CHENOPODIACEAE (p. 147).

Fruit with more than 1 seed, usually dehiscent; petals nearly always
present.

Sepals and petals each 4, the sepals distinct; flowers never blue, mostly
in TaceMES........ 2.2.22... BRASSICACEAE (p. 163).
Sepals and petals each 5; flowers sometimes blue.

Calyx of united sepals; flowers regular. Fruit a capsule, or of 5 or
more carpels arranged in a ring; stipules present.

MALVACEAE (p. 202).
Calyx of distinct sepals; flowers often very irregular.

Leaves with stipules; fruit an obtuse capsule. Petals bluish.

Viola (p. 206).
Leaves without stipules; fruit of numerous achenes, of several

follicles, or a head of berries... RANUNCULACEAE (p. 156).
Leaves not lobed, merely toothed.

Corolla of united petals, colored. Fruit a capsule ora berry.
Calyx borne on the top of the ovary or fruit; corolla blue or red.
Corolla split down one side, irregular; stamens united by their anthers.

LOBELIACEAE (p. 263).
Corolla not split on one side, regular; stamens free.

CAMPANULACEAE (p. 262).
Calyx borne at the base of the ovary or fruit and free from it; corolla usually
yellow or white, never red.
Flowers in spikes or racemes; fruit a smooth capsule..Verbascum (p. 249).
Flowers axillary or in cymes; fruit a berry or a spiny capsule.

SOLANACEAE (p. 247).
Corolla of distinct petals, or none.

Petals none, the calyx small, green; fruit 1-seeded or a 3 or 5-lobed capsule.
Plants not hairy, or sometimes with glandular hairs; flowers mostly in
terminal panicles, cymes, or panicled spikes; stipules none. Fruit
1-seeded or of 5 or 6 carpels.
Fruit 1-seeded, indehiscent; plants usually glandular-hairy or white-
mealy; flowers never in 1-sided cymose spikes.

CHENOPODIACEAE (p. 147).
Fruit many-seeded, dehiscent; plants glabrous; flowers in 1-sided spikes.

PENTHORACEAE (p. 171).
Plants hairy, but the hairs never glandular; flowers in axillary clusters or
spikes; stipules present.

Flowers in spikes; plants without stinging hairs; fruit a 3-lobed capsule.

Acalypha (p. 195).
Flowers in cymes; plants with stinging hairs; fruit an achene.

Urticastrum (p. 142).
Petals present; fruit not I-seeded, but sometimes of numerous achenes.

Calyx borne on the top of the fruit or ovary and united with it. Petals
mostly yellow..............020.0.22-2.0. 00000. ONAGRACEAE (p. 212).

Calyx borne at the base of the ovary or fruit and free from it.
Corolla very irregular, one of the petals spurred.
Stipules present; leaves about as broad as long and usually cordate
at the base, or, if much longer than broad, very hairy; petals white,
yellow, greenish, or blue................... VIOLACEAE (p. 206).
Stipules none; leaves much longer than broad, narrowed at the base,
abrous; petals yellow or orange...IMPATIENTACEAE (p. 201).

FLORA OF THE DISTRICT OF COLUMBIA. 41

Corolla regular or nearly so, none of the petals spurred.
Leaves very thick and succulent. Petals pink or purple; fruit of
several many-seeded follicles......-..------+-+-+- Sedum (p. 171).
Leaves thin, never fleshy.
Sepals and petals each 4. Fruit a 1 or 2-celled pod, usually much
longer than wide; stipules none; flowers mostly in racemes.
BRASSICACEAE (p. 163).
Sepals or calyx lobes and petals each 5.
Sepals distinct; fruit of numerous achenes. Petals yellow.
Ranunculus (p. 158).
Sepals united, at least below; fruit not of achenes.
Leaves mostly basal, hairy, the blades rounded, cordate at the
base; fruit a 1-celled capsule. Flowers in racemes.
Heuchera (p. 171).
Leaves mostly borne on the stems; fruit not a 1-celled capsule.
Stipules none; flowers in 1-sided spikes; plants glabrous.
PENTHORACEAE (p. 171).
Stipules present; flowers never in 1-sided spikes; plants
usually pubescent.....--.------- MALVACEAE (p. 202).

KEY TO THE FAMILIES BASED MAINLY ON FLORAL CHARACTERS.
Division I. PTERIDOPHYTA. Ferns and fern allies.

Plants without true flowers, reproducing by spores (no embryo being formed);
fernlike, mosslike, or rushlike plants.

Plants aquatic, inhabiting rock pools and tidal shores: leaves rushlike, tufted
upon a very short trunk; sporangia borne within the hollow leaf bases.
ISOETACEAE (p. 60).
Plants terrestrial; leaves not rushlike; sporangia not borne within hollow leaf bases.
Stems hollow, jointed, grooved, rough; leaves reduced to toothed sheaths surround-
ing the joints............------- eee eee eee eee EQUISETACEAE (p. 58).
Stems not hollow, jointed, grooved, or rough; leaves minute to very large, never
reduced to sheaths upon the stem.
Leaves minute (1 cm. long or less) and exceedingly numerous, sessile, awllike or
bractlike, 4-many-ranked; plants more or less mosslike.
Plants depressed or short-creeping, not over 3 or 4 cm. high; spores of 2 kinds,
megaspores and microspores.....----------- SELAGINELLACEAE (p. 60).
Plants mostly wide-creeping, the simple erect peduncles or bushy aerial branches
10-30 cm. high; spores of one kind, very minute.
LYCOPODIACEAE (p. 59).
Leaves very much larger, few, not awllike or bractlike, stalked, fascicled or
obscurely 2-ranked; plants not mosslike.
Plants vinelike, twining; pinne palmately 4-7-lobed, borne alternately in pairs.
SCHIZAEACEAE (p. 53).
Plants not vinelike or twining; pinne not palmately lobed or borne in pairs.
Sporangia large, sessile, borne in a s‘alked terminal spike or loose panicle,
the sterile blade appearing lateral, simple and entire or several times
pinnately divided.............--------- OPHIOGLOSSACEAE (p. 52).
Sporangia small, stalked, borne in clusters (sori) on the back of ordinary
foliage leaves or modified parts of these, or wholly concealed within the
hard berry-like or podlike divisions of greatly modified, wholly fertile
leaves.

42 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Sporangia associated in definite clusters (sori) on the under side or at the
margins of ordinary leaves, or within the hard, contracted divisions of
wholly fertile, greatly modified leaves, long-stalked, with a nearly
complete vertical ring, rupturing transversely.

POLYPODIACEAE (p. 53).

Sporangia covering thickly some or all pinne of the fertile fronds, replacing
the ordinary leaf tissue, short-stalked, with a rudimentary apical ring,
opening by a longitudinal slit............. OSMUNDACEAE (p. 52).

Division II. SPERMATOPHYTA. Flowering plants.
Plants with true flowers, reproducing by seeds, these containing an embryo.

Subdivision I. GYMNOSPERMAE.

Ovules not in a closed ovary. Trees with scalelike or needle-like evergreen leaves,
the fruit a cone or berry. A single family...................... PINACEAE (p. 60).

Subdivision HI. ANGIOSPERMAE.

Ovules in a closed ovary, this at maturity becoming the fruit.

Class I. MONOCOTYLEDONEAE.

Stems in cross section showing the vascular strands or fibers distributed uregularly
through the pith, as in the cornstalk; embryo with a single cotyledon; parts of the
flower usually in 3’s or 6’s, never in 5’s; leaves usually parallel-veined. Our species,
with the exception of the genera Arundinaria and Smilax, are herbaceous. In some
groups the stems are hollow, except at the nodes; in these cases the vascular strands are
aggregate in the exterior zone and may appear as if in a ring. The leaves are net-
veined in Dioscorea, Trillium, and several other genera with broad blades, but even in
these they are ribbed with more or less prominent main veins running from base to
apex. In the family Lemnaceae there is no distinction between stem and leaf. In
some books this class is called endogens. ‘

Perianth none.
Plants free-floating aquatics, consisting of small ovoid or disk-shaped fronds, less
than 10 mm. long...........0. 2.2.2 e cece eee cece cece LEMNACEAE (p. 114).
Plants with stems and leaves, the latter sometimes reduced to scales.
Plants immersed aquatics, branching and leafy, the upper leaves often floating.
Flowers perfect, in spikes; leaves alternate.. POTAMOGETONACEAE (p. 62).
Flowers unisexual, axillary, the plants dioecious; leaves opposite.

NAIADACEAE (p. 64).
Plants terrestrial or growing in marshes, not immersed.

Flowers subtended or surrounded by small bracts, and aggregate in spikelets;
grasslike plants, (See also Sparganiaceae.)
Leaves 2-ranked, the sheaths usually split; flowers with a second small bract
(palea) next to the rachilla; stems cylindric or flattened, usually hollow.
POACEAE (p. 66).
Leaves 3-ranked, the sheaths not split; flowers with no second bract next
to the rachilla; stems solid, usually triangular....CYPERACEAE (p. 92).
Flowers not subtended by bracts, unisexual, the staminate above, the pistillate
below on the same axis.
Leaves petioled, the blade (sometimes divided) net-veined; spike of flowers
usually inclosed in a large spathe................. ARACEAE (p. 113).
Leaves not petioled, linear, elongate; spike of flowers not inclosed in a spathe.
TYPHACEAE (p. 62).

FLORA OF THE DISTRICT OF COLUMBIA. 43

Perianth present, sometimes small and scalelike.
Divisions of perianth small and scalelike, often shorter than the ovary, free from the
ovary (see also Dioscoreaceae).
Leaves petioled, the blades broad and net-veined.........-- ARACEAE (p. 113).
Leaves not petioled, linear,
Flowers in a single whitish involucrate head....ERIOCAULACEAE (p. 115).
Flowers cymose or in heads, the latter not involucrate.
Flowers unisexual, in dense heads, the plants monoecious; perianth of a few
obtuse scales, shorter than the fruit...... SPARGANIACEAE (p. 62).
Flowers perfect; perianth of 6 greenish or brownish divisions.
JUNCACEAE (p. 117),
Divisions of perianth more or less petal-like, colored or sometimes greenish.
Pistils several or many in a head or ring. Perianth of 3 outer green sepals and
3 inner white petals; marsh herbs..........-.------ ALISMACEAE (p. 64).
Pistil one, the cells or placentz usually 3.
Perianth free from the ovary.
Stamens 3.
Flowers in a long-peduncled ovoid head; petals yellow; erect marsh or
bog plants with long narrow basal leaves..... XYRIDACEAE (p. 115).
Flowers few from a short-peduncled spathe; petals yellow, blue, or white;
low creeping aquatic plants with scattered leaves,
Heteranthera (p. 116).
Stamens 6 (rarely 4).
Perianth of 3 herbaceous or greenish sepals and 3 colored petals.
Leavesin a whorl of 3 below the flower; petals withering only with age.
Trillium (p. 124).
Leaves more than 3, not in whorls; petals delicate, quickly withering.
COMMELINACEAE (p. 115).
Perianth of 6 divisions, these similar in color, sometimes irregular in shape.
Stamens dissimilar, 3 much longer than the other 3. Aquatic herbs
with cordate petioled leaves and purplish flowers in dense spikes.
Pontederia (p. 116).
Stamens similar.
Plants climbing by tendrils. Fruit a berry. SMILACACEAE (p. 124).
Plants without tendrils.
Fruit a berry; basal leaves wanting. Rootstocks present.
. CONVALLARIACEAE (p. 123).
Fruit a capsule; basal leaves usually present.
Styles 3 (united below in Uvularia); bulbs and corms usually
wanting ....-.-...-....--.20--- MELANTHIACEAE (p.119).
Style 1; bulbs or corms usually present.. LILIACEAE (p. 120).
Perianth adnate to the ovary.
Flowers irregular; stamens 1 or 2; ovules very numerous.
ORCHIDACEAE (p. 127).
Flowers regular; stamens 3-6; ovules few or numerous.

Plants aquatic, submerged.......-.--------- VALLISNERIACEAE (p. 66).
Plants terrestrial, sometimes growing in marshes.
Stems twining; leaves cordate............ DIOSCOREACEAE (p. 125).

Stems not twining; leaves linear.
Stamens 6; leaves not equitant; outer perianth divisions greenish
below....--0---ceeeeeeeceeecseees AMARYLLIDACEAE (p. 125).
Stamens 3; leaves equitant; perianth divisions similar.
IRIDACEAE (p. 126).

44 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Class II. DICOTYLEDONEAE,

Stems in cross section showing a central pith surrounded by a circle or ring of
vascular strands, these often merged into a zone of wood; embryo with two cotyle-
dons; parts of the flower usually in 4’s or 5’s; leaves net-veined. This class has
also been called exogens because there is, especially in the woody plants, a division
of the stem into wood and bark with a growing (cambium) layer between, the increase
in diameter being by additions from the cambium to the outer part of the wood and
to the inner part of the bark.

Division I. CHORIPETALAE.

Petals distinct or wanting. The two lower petals are more or less coherent in
Fabaceae; the inner pair of petals is united over the stigma in Fumariaceae; thiee
petals are somewhat coherent in Polygalaceae; all the petals are slightly united at
base in Oxalis, Iler, and Malvaceae. The division is also called Archichlamydeae.
The group without petals has been called Apetalae; the group with distinct petals
has been called Polypetalae.

A. Petals none, the sepals sometimes colored like petals. In flowers with superior
ovary, if only one series of floral envelopes is present, this is assumed to be the
calyx. In flowers with inferior ovary the corolla may be present and the calyx
wanting or represented by scales or bristles; such flowers are considered under the
division, ‘‘petals present,’? or under Gamopetalae.

Flowers unisexual, one or both kinds in catkins or aments. Trees or shrubs.
Staminate and pistillate flowers in catkins.
Ovary many-ovuled. Seeds with copious silky hairs; calyx wanting; stipules
present...............00.00.20 20220222200 SALICACEAE (p. 132).
Ovary with 1 ovule in each cell.
Leaves narrow, acute at base, broadest above the middle; calyx wanting;

stipules wanting.........2.2.02..0..0..0.0002. MYRICACEAE (p. 135).
Leaves ovate to oblong, broadest below the middle; calyx present; stipules
present........ 00.00.2000 eee eee ee eee eee BETULACEAE (p. 136).

Staminate flowers in catkins; pistillate flowers single or clustered (an oblong or
spheric head in Moraceae).
Pistillate flowers in an oblong or spheric head. Leaves simple.

MORACEAE (p. 141).
Pistillate flowers single or few in a cluster.

Leaves pinnate; fruit a large nut inclosed in a dehiscent or indehiscent
smooth covering or shuck, the meat or embryo 4-lobed.

JUGLANDACEAE (p. 135).

Leaves simple; fruit an acorn, or a nut inclosed in a prickly involucre, the

meat not lobed............. cee eee cee eeee .....FAGACEAE (p. 137).
Flowers not in catkins, perfect or unisexual.
Plants woody (trees or shrubs), ’
Leaves opposite.
Plant a parasite on the branches of trees....... LORANTHACEAE (). 143).

Plants not parasitic.
Twigs green or red; fruit a pair of asymmetric samaras; leaves simple
(pinnate in Rulac)............2202.22022- 22 0ee ACERACEAE (p. 200).
Twigs gray; fruit a single symmetric samara; leaves pinnate,

Fraxinus (p. 227).
Leaves alternate.

Flowers (at least the pistillate) in dense globose peduncled heads; leaves
about as broad as long, palmately lobed or veined.
Leaves deeply 3-7-lobed; branchlets usually corky-winged.
Liquidambar (p. 173).

FLORA OF THE DISTRICT OF COLUMBIA. 45

Leaves shallowly but sharply several-lobed; twigs smooth.
PLATANACEAE (p. 173).
Flowers clustered, but not in dense globose heads; leaves ovate to elliptic;
not lobed (sometimes 3-lobed in Sassafras).
Twigs and leaves strongly aromatic; anthers opening by uplifting lids.
LAURACEAE (p. 161).
Twigs and leaves not aromatic; anthers not opening by lids.
Leaves serrate (sometimes entire in Celtis), very oblique at base.
ULMACEAE (p. 140).
Leaves entire.
Winter buds pubescent; calyx cup-shaped, scarcely toothed; a shrub.
DAPHNACEAE (p. 211).
Winter buds glabrous; calyx deeply 5-toothed; a tree..Nyssa (p. 220).
Plants herbaceous.
Ovary or its cells containing several or many ovules.
Calyx none; plant a small aquatic ...........PODOSTEMACEAE (p. 171).
Jalyx present; plants terrestrial or sometimes growing in water.
Ovary inferior.
Ovary 6-celled; stamens 6-12; plants terrestrial.
ARISTOLOCHIACEAE (p. 143).
Ovary 1 or 4-celled; plants growing in water or on mud.

Ovary 1-celled; stamens 8-10...........---- Chrysosplenium (p. 171).

Ovary 4-celled; stamens 4............------------- Ludwigia (p. 213).
Ovary superior.

Ovaries 2 or more, distinct.......-....-.-- RANUNCULACEAE (p. 156).

Ovary single.
Leaves compound or deeply many-lobed.
RANUNCULACEAE (p. 156).
Leaves simple.
Leaves alternate. Ovary 5-celled, 5-beaked.

PENTHORACEAE (p. 171).
Leaves opposite or whorled.

Capsule 3-celled; leaves whorled........... AIZOACEAE (p. 150).
Capsule 1-celled; leaves opposite........ ALSINACEAE (p. 151).
Ovary or its cells containing 1 or 2 ovules.....-..-. ee ere B, BB.

B. PISTILS MORE THAN ONE, DISTINCT OR NEARLY SO.

Calyx none. Flowers in nodding spikes; leaves cordate. .SAURURACEAE (p. 132).
Calyx present.
Stamens inserted on the calyx; stipules present.........-------- Aphanes (p. 177).
Stamens inserted on the receptacle; stipules none. ..RANUNCULACEAE (p. 156).

BB. PISTILS SINGLE, SIMPLE OR COMPOUND.

Ovary inferior or so closely invested by the calyx tube as to appear so.
Plants aquatic, the submersed leaves finely divided.
HALORAGIDACEAE (p. 214).
Plants terrestrial.
Leaves opposite; flowers rose or purple, 3-5 in a broad thin involucre.
ALLIONIACEAE (p. 149).
Leaves alternate; flowers without an involucre.
Leaves simple; flowers white, in panicles...........SANTALACEAE (p, 143).
Leaves pinnate; flowers in spikes........--.---------+-- Sanguisorba (p. 177).

46 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Ovary superior.
Stipules sheathing the stem at the nodes............. POLYGONACEAE (p. 144).
Stipules, if present, not sheathing the stem.
Plants aquatic, submersed or growing on mud, low and delicate.
Leaves whorled, dissected; style 1......... CERATOPHYLLACEAE (p. 155).
Leaves opposite, entire; styles 2.............. CALLITRICHACEAE (p. 197).
Plants not aquatic.
Styles 10. Berry 10-seeded; flowers in racemes.
PHYTOLACCACEAE (p. 150).
Styles (if present) and stigmas 1-3.

Leaves palmately lobed or divided...................... Cannabis (p. 142).
Leaves not palmately lobed.
Ovary 3-celled............0......22.2-2.--.- EUPHORBIACEAE (p. 194).

Ovary 1—-2-celled.
Ovary 2-celled; flowers in racemes. Pod 2-seeded, circular, flat.
Lepidium (p. 166).
Ovary 1-celled; flowers not in racemes.
Leaves with branched hairs beneath..........-. Crotonopsis (p. 195).
Leaves without branched hairs.
Stipules present.
Flowers unisexual; leaves toothed (except Parietaria).
URTICACEAE (p. 142).

Flowers perfect; leaves entire...... CORRIGIOLACEAE (p. 150).
Stipules none.
Perianth and bracts scarious...... AMARANTHACEAE (p. 148).

Perianth and bracts (if present) herbaceous, not scarious.
CHENOPODIACEAE (p. 147).
AA. Petals present.
Pistils more than 1, distinct (inclosed in a fleshy receptacle in Rosa).

Stamens inserted on the calyx (hypanthium).............. ROSACEAE (p. 173).
Stamens inserted on the receptacle.
Stamens united in a column by their filaments........ MALVACEAE (p. 202).

Stamens distinct.
Plants succulent. Stamens twice as many as the petals; follicles many-
seeded... 2... ee ee cece cee eee eee eee eee CRASSULACEAE (p. 171).
, Plants not succulent.
Plants woody.
Plants climbing; leaves peltate......... MENISPERMACEAE (p. 161).
Plants not climbing; leaves not peltate.
Stipules encircling the stem, deciduous but leaving a ring on the
twigs........ 2. eee eee eee MAGNOLIACEAE (p. 161).
Stipules none................0 0.0 cee eee ee ANNONACEAE (p. 161).
Plants herbaceous.
Sepals and petals 3.

Plants aquatic............2......0.....--. CABOMBACEAE (p. 155).

Plants terrestrial.......... eee eee e eee LIMNANTHACEAE (p. 198).
Sepals and petals 4 or 5.

Carpels distinct.....................2.. RANUNCULACEAE (p. 156).
Carpels united at base.

. Pistil 5-lobed............................G@ERANIACEAE (p. 190),

Pistil 2-lobed..........0.2222e2eee eee SAXIFRAGACEAE (p. 171).

Pistil single.
Leaves punctate with translucent dots.
Leaves simple; herbs or low shrubs; fruit a capsule.
HYPERICACEAE (p. 204).

FLORA OF THE DISTRICT OF COLUMBIA. 47

Leaves trifoliolate; a tall shrub; fruit a winged nutlet.... RUTACEAE (p. 192),
Leaves not punctate.
C. Plants woody.
Plants climbing.

Tendrils present............-.--.--- 220-2 e cece eee eee VITACEAE (p. 201).
Tendrils none.
Stems twining; leaves simple.............-.-------- Celastrus (p. 199).

Stems climbing by rootlets; leaves compound. .Toxicodendron (p. 198).
Plants not climbing.
‘Leaves opposite.
Leaves compound.
Leaves pinnate, with 5 or more leaflets...........- Fraxinus (p. 227),
Leaves 3-foliolate...........-.-...----- STAPHYLEACEAE (p. 200).
Leaves simple.
Fruit fleshy, indehiscent.
Flowers in cymes; stone 2-celled........... CORNACEAE (p. 219).
Flo -* in pan‘cles; stone l-celled........... OLEACEAE (p. 227).
Fruit dry (aril fleshy in Euonymus).
" Ovary 2-celled.
Fruit a pair of asymmetric samaras; leaves lobed or compound.
ACERACEAE (p. 200).
Fruit a capsule; leaves not lobed.. HYDRANGEACEAE (p. 172).
Ovary 4-celled; fruit a 4 (3-5) -celled capsule, the aril red.

Euonymus (p. 199).
Leaves alternate.

Pistil a single carpel, forming in fruit a 1-celled pod.

Corolla papilionaceous......................04. FABACEAE (p. 181),
Corolla not papilionaceous, the odd petal inside the others, nearly
regular except in Cercis............ CAESALPINIACEAE (p. 180).

Pistil compound, consisting of more than 1 carpel.
Leaves compound.
Plant prickly:.... 2.0.0... cee eee ee eee tee eee ARALIACEAE (p. 215).
Plants not prickly.
Ovary 2-5-parted, each part becoming in fruit a samara.
SIMAROUBACEAE (p. 193).
Ovary entire; fruit a slightly fleshy drupe.

ANACARDIACEAE (p. 198).
Leaves simple.

Stamens more than 10.
Fruit a globose nut; cluster of flowers attached to a leaflike bract.
TILIACEAE (p. 202.)
Fruit fleshy; flowers not attached to a leaflike bract.

Fruit a pome, several-seeded...........- MALACEAE (p. 177).

Fruit a drupe, l-seeded............ AMYGDALACEAE (p. 179).
Stamens 10 or fewer.

Stamens 5, opposite the petals..........RHAMNACEAE (p. 201).

Stamens not of the same number as the petals, or, if of the same
number, alternate with them.
Calyx tube adherent to at least the lower part of the ovary.
Ovules 1 in each cell; leaves toothed; fruita capsule. Flowers
appearing in late autumn........... Hamamelis (p. 172).
Ovules several in each cell; leaves lobed; fruit a berry.
GROSSULARIACEAE (p. 172).

48

CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Calyx tube free from the ovary.
Fruit fleshy, a berry-like drupe. .AQUIFOLIACEAE (p. 199).
Fruit a capsule.
Capsule 2-celled; style about equaling the stamens.
ESCALLONIACEAE (p. 172).
Capsule 3-celled; style much longer than the stamens.
CLETHRACEAE (p. 220).
CC.¥Plants herbaceous (slightly woody in Pyrolaceae).
Stamens more than 10.
Stems succulent, flat, the leaves reduced to scales; ovary inferior.
CACTACEAE (p. 211).
Stems not succulent and flat, the leaves developed; ovary superior (calyx
slightly adherent in Castalia).
Plants aquatic, with broad floating or emersed blades.
NYMPHAEACEAE (p. 155).
Plants terrestrial.

Filaments united in a tube.............-.--- MALVACEAE (p. 202).
Filaments separate.
Leaves peltate, lobed...................- ...Podophyllum (p. 160).
Leaves not peltate.
Leaves compound............... .. RANUNCULACEAE (p. 156).

Leaves simple.
Leaves tubular (hollow and pitcher-shaped).
SARRACENIACEAE (p. 170).
Leaves not hollow.
Leaves fleshy.........-...--.-- PORTULACACEAE (p. 150).
Leaves not fleshy.
Calyx tubular, 6-toothed; plants viscid. Parsonsia (p. 212).
Calyx of distinct sepals; plants not viscid.
Sepals 2; juice colored....... PAPAVERACEAE (p. 162).
Sepals 3-5; juice not colored...... CISTACEAE (p. 205).
Stamens 10 or fewer. .
Stamens as many as petals and opposite them. BERBERIDACEAE (p. 160).
Stamens not of same number as petals and opposite them.
Ovary inferior (partly inferior in Portulaca and Saxifragaceae).
Ovules and seeds more than 1 in each cell.
Ovary 1-celled.
Sepals or calyx lobes 2; plants succulent.
PORTULACACEAE (p. 150).
Sepals or calyx lobes 4 or 5; plants not succulent.
SAXIFRAGACEAE (p. 171).
Ovary 2—4-celled.
Anthers opening by terminal pores; leaves 3-ribbed.
MELASTOMATACEAE (p. 212).
Anthers not opening by pores; leaves not 3-ribbed.
Ovary slightly inferior; styles 2............- Saxifraga (p. 172).
Ovary wholly inferior; style 1, the stigma often lobed.
ONAGRACEAE (p. 212).
. Ovules and seeds single in each cell.

Flowers in simple or compound umbels; stamens 5.
Fruit dry, splitting into seedlike carpels..... APIACEAE (p. 215).
Fruit fleshy, a 2-5-seeded drupe......... ARALIACEAE (p. 215).
Flowers in spikes.
Plants aquatic, with dissected leaves..... Myriophyllum (p. 214).
Plants terrestrial, the leaves not dissected........ Gaura (p. 213).

FLORA OF THE DISTRICT OF COLUMBIA. 49

Ovary superior.
Ovary simple.

Flowers papilionaceous...........---------+-+- FABACEAE (p. 181).
Flowers not papilionaceous.......... CAESALPINIACEAE (p. 180).

Ovary compound (the cells, placente, styles, or stigmas more than 1).
D, DD.

D. OVARY 1-CELLED,
Corolla irregular.
Petals 4; stamens 6............2.20 222s eee eee eee eee FUMARIACEAE (p. 163).
Petals 5; stamens 5..........----0- 2 ee eee ee cee cette etree VIOLACEAE (p. 206).
Corolla regular or nearly so.
Placente central.

Petals inserted on the throat of the calyx.........-.--- LYTHRACEAE (p. 211).
Petals not inserted on the calyx.
Sepals distinct; petals not stalked........-....------- ALSINACEAE (p. 151).
Sepals united; petals stalked..........------+--++++- SILENACEAE (p. 153).

Placentze on the sides of the ovary.
Leaves with conspicuous stalked glands, Low bog plants.
DROSERACEAE (p. 170).
Leaves not conspicuously glandular.
Petals 5; plants climbing by tendrils.........-.- PASSIFLORACEAE (p. 211).
Petals 4; stamens 6; plants not climbing.
Pod beaked, indehiscent, 2-3-seeded; leaves pinnately lobed.
Raphanus (p. 170).
Pod dehiscent, many-seeded; leaves palmately compound.
CAPPARIDACEAE (p. 170).

DD. OVARY 2-SEVERAL-CELLED.
Flowers irregular.

Flowers spurred; leaves crenate-toothed..........--- IMPATIENTACEAE (p. 201).

Flowers not spurred; leaves entire.........-.---++++-- POLYGALACEAE (p. 193).
Flowers regular or nearly so.

Plants without chlorophyll..............-----------MONOTROPACEAE (p. 221).

Plants with chlorophyll.
Stamens 6 (sometimes 2 in Lepidium); petals 4. Flowers usually in racemes.
BRASSICACEAE (p. 163).
Stamens as many or twice as many as the petals.
Ovules 1 or 2 in each cell.
Ovary deeply lobed; pod long-beaked, dehiscing elastically from the base;
leaves lobed or divided...........-------++-- GERANIACEAE (p. 190).
Ovary not lobed, appearing 10-celled from partitions between the seeds, not
long-beaked nor dehiscing from the apex; leaves entire.
LINACEAE (p. 192).
Ovules, and usually seeds, several in each cell.
Leaves 3-foliolate..........---..-- cece eee er cece OXALIDACEAE (p. 191).
Leaves simple.
Stipules present between opposite leaves. A low marsh annual.
ELATINACEAE (p. 205).
Stipules none when the leaves are opposite.
Leaves alternate; foliage evergreen...-...--.-- .PYROLACEAE (p. 220).
Leaves opposite; foliage not evergreen........- LYTHRACEAE (p. 211).

69289—19——4

50

CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Division II. GAMOPETALAE.

Petals present and united, at least at the base. Also called Sympetalae and
Metachlamydeae.

Stamens not more numerous than the lobes of the corolla.
Plants herbaceous, without. chlorophyll..................... -Monotropsis (p. 221).
Plants woody, sometimes low and creeping, with chlorophyll.

Ovary inferior. ..........0.000.0000000 002 -ee cee eee. VACCINIACEAE (p. 224).
Ovary superior.
Fruit dehiscent, usually dry; shrubs.......:.......... ERICACEAE (p. 222).
Fruit a large berry with several flat seeds; a tree.. DIOSPYRACEAE (p. 227).

Stamens not more numerous than the corolla lobes.
Stamens opposite the lobes of the corolla, equaling them in number.

Stamens alternate with the lobes of the corolla or fewer,

PRIMULACEAE (p. 225).

Ovary inferior.
Tendrils present............................... CUCURBITACEAE (p. 262).
Tendrils none.
Stamens united by their anthers.
Flowers separate, not involucrate............... -LOBELIACEAE (p. 263).
Flowers in dense heads surrounded by an involucre,
Corolla strap-shaped in all the flowers of the head. Juice milky; leaves
alternate..........0000000 0.002220. CICHORIACEAE (p. 263).
Jorollas all tubular, or only the outer ones strap-shaped.
Flowers unisexual, the 2 kinds in separate unlike heads; involucre
of the pistillate heads coriaceous and spiny or tuberculate, forming
a bur inclosing the achenes; ray flowers none. Flowers greenish
or yellowish. ..........020.20000.... AMBROSIACEAE (p. 267).
Flowers all perfect, or both kinds in the same head or rarely in separate
heads, but the heads then all similar in general appearance (except
in Baccharis), involucre not coriaceous and spiny, not inclosing
the achenes as a bur; ray flowers usually present.

ASTERACEAE (p. 268).
Stamens distinct.

Leaves alternate; stamens free from the corolla or nearly so. Juice milky.
CAMPANULACEAE (p. 262).

Leaves opposite or whorled; stamens inserted on the corolla.
Stamens 1-3, fewer than the corolla lobes. Ovary consisting of a fertile
1-ovuled cell and 2 empty or abortive cells; herbs, without stipules.

VALERIANACEAE (p. 261).
Stamens 4 or 5.

Ovary 1-celled. Flowers in dense involucrate heads; herbs, without
stipules...........22..... eee eee eee ee DIPSACACEAE (p. 262).
Ovary 2-5-celled.
Leaves without stipules (except Viburnum pubescens), opposite.
CAPRIFOLIACEAE (p. 259).

Leaves with stipules, or whorled............ RUBIACEAE (p. 257).
Ovary superior.

Plants woody.
Leaves opposite.
Corolla irregular; fruitacapsule............... BIGNONIACEAE (p. 254).
Corolla regular; fruit indehiscent, dry or fleshy... .. OLEACEAE (p. 227).
Leaves alternate.
Ovary 2-celled; fruit a berry........................... Lycium (p. 247).
Ovary 3-10-celled; fruit a dry (or sometimes fleshy) capsule.
ERICACEAE (p. 222).

FLORA OF THE DISTRICT OF COLUMBIA. 51

Plants herbaceous. oe + i ia
Ovaries more than 1, or, if 1, deeply lobed.
Ovary deeply 4-lobed.
Leaves alternate; corolla regular (irregular in Hchium); stems terete.
BORAGINACEAE (p. 237).
Leaves opposite; corolla usually 2-lipped; stems 4-sided.
MENTHACEAE (p. 239).
Ovaries 2, or solitary and 2-horned.

Stamens united..........-.-.--------+-+ ASCLEPIADACEAE (p. 231)
Stamens distinct.
Ovary 2-horned; stipules present........... LOGANIACEAE (p. 228).
Ovaries 2; stipules none. ......-.....-.---- APOCYNACEAE (p. 229).

Ovary 1, not deeply lobed.
Corolla irregular; anther-bearing stamens 2 or 4 (except Echium and Ver
bascum with 5).
Ovules solitary in the 1-4 cells.
Ovary l-celled; fruit reflexed...........---- PHRYMACEAE (p. 256).
Ovary 2-4-celled; fruit not reflexed ....... VERBENACEAE (p. 239).
Ovules 2 to many in each cell.
Ovary 1-celled.
Plants terrestrial, without chlorophyll; stamens 4.
OROBANCHACEAE (p. 254).
Plants aquatic or growing on mud, chlorophyll-bearing; stamens 2.
PINGUICULACEAE (p. 255).
Ovary 2-celled.
Capsule elastically dehiscent; seeds few, borne on hooklike processes

of the placentee.......-----2222e2 ees ACANTHACEAE (p. 255).
Capsule not elastically dehiscent; seeds numerous, not borne on
hooks ....222ececeeeeceeeeees SCROPHULARIACEAE (p. 248).

Corolla regular.
Stamens fewer than the corolla lobes.
Stamens with anthers 4.

Ovary 2-celled; cells several-seeded .....-.-.---.- Ruellia (p. 256).

Ovary 2—4-celled; cells 1-seeded:........ VERBENACEAE (p. 239).
Stamens with anthers 2.

Leaves basal; corolla scarious. - .--- - - PLANTAGINACEAE (p. 256).

Leaves arranged along the stem; corolla not scarious. Veronica (p. 252).
Stamens as many as the corolla lobes.
Ovary 1-celled.
Leaves entire, opposite..................GENTIANACEAE (p. 228).
Leaves toothed, lobed, or compound, alternate.
HYDROPHYLLACEAE (p. 236).
Ovary 2—4-celled.
Plants leafless twining parasites, without chlorophyll.
CUSCUTACEAE (p. 234).
Plants with chlorophyll, not parasitic.
Ovary 4-celled; fruit separating into 4 nutlets; plants rough-hairy.
Heliotropium (p. 237).
Ovary 2-3-celled; fruitacapsule or berry; plants glabrous or pubes-
cent but not rough-hairy.
Ovary and capsule 3-celled, the style 3-lobed.
POLEMONIACEAE (p. 235).
Ovary and capsule or berry 2-celled.
Seeds few, mostly 4; fruit a capsule; plants usually twining.
CONVOLVULACEAE (p. 233).
Seeds many; fruit a capsule or berry; plants not twining
(except Solanum dulcamara) ....- SOLANACEAE (p. 247).

52 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

ANNOTATED LIST OF SPECIES.
1. OPHIOGLOSSACEAE. Adder’s-tongue Family.

Sterile blade simple, entire, with netted veins; sporangia united in 2 rows ina simple

slender fleshy spike ............ 0000000002 cece eee e eee ee 1. OPHIOGLOSSUM.
Sterile blade 1-3 times pinnately divided, with free veins; sporangia globose, all
distinct, borne in a 14-pinnate panicle. .................... 2. BOTRYCHIUM.

1. OPHIOGLOSSUM L. ADDER’S-TONGQUE.

1. Ophioglossum vulgatum L.
Low moist woods or partially shaded grassy slopes; numerous localities, but nowhere

abundant. June-July. Eastern N. Amer.; also in Eur. and Asia,
4

2. BOTRYCHIUM Swartz. GRAPE FERN.

Sterile blade sessile, the common stalk nearly all above ground; leaf tissue very thin;

spores maturing in J UNG... eee eee eee eee 1. B. virginianum.

Sterile blade long-stalked, the common stalk nearly all below ground; leaf tissue

much firmer; spores maturing in autumn.

Segments of the sterile blade mostly acute, the margins minutely toothed.

2. B. obliquum.,

Segments of the sterile blade less acute, deeply cut into slender spreading teeth.

3. B. dissectum.

1. Botrychium virginianum (L.) Swartz. RATTLESNAKE FERN,

Woods; abundant; attaining its best development in rich hilly woods on the
Virginia side of the upper Potomac. First of June. Widely distributed in N. Amer.
2. Botrychium obliquum Muhl.

Low brushy pastures amd moist thin woods; common. Aug.—Oct. Eastern N.
Amer. (B. ternatum obliquum D. C. Eaton.)
8. Botrychium dissectum Spreng.

Moist woods or thickets; common, but less so than B. obliquum. Aug.-Oct. Me.
to Va. and Ky.

Botrychium neglectum Wood has been reported, probably in error.

2. OSMUNDACEAE. Flowering fern Family.

1. OSMUNDA L.

Blades coarsely bipinnate, the large segments distant, sessile or short-stalked; apical
pinnee of some of the blades fertile, contracted, forming an upright terminal

panicle... 2.2... 0... cece ee ccc eee cece ce cencececcececeece 1. O. regalis.
Sterile blades or parts of blades once pinnate, the pinnsz pinnatifid into small close
lobes.

Blades normally of two kinds, wholly fertile or sterile, the former cinnamon-colored,
succulent at maturity but quickly withering and disappearing; pinne of
sterile blade bearing a tuft of tomentum at base...... 2. O. cinnamomea,

Blades either wholly sterile or with 2-6 pairs of middle pinne fertile, these shrivel-
ing after maturity but persistent; sterile pinne lacking tuft of tomentum at
DaSC 2. eee eee cece eee cece cece cceccceeeccee 3. O. claytoniana.

1. Osmunda regalis L. RoyAL FERN,
Swamp borders and boggy woods; not uncommon. May-June. N. Amer, generally;
also in Eur.

FLORA OF THE DISTRICT OF COLUMBIA. 53

2. Osmunda cinnamomea L. CINNAMON FERN.
Wet woods, swamps, and low cut-over areas; abundant. May. Most of eastern
N. Amer.; also in Asia.
The spring stage, often known as fiddleheads, is shown in plate 11.
3. Osmunda claytoniana L. INTERRUPTED FERN.
Swamp edges, moist wooded slopes, or sandy alluvial soil; not very common, but
found throughout. May. Eastern N. Amer.; also in Asia,

3. SCHIZAEACEAE. Curly-grass Family.
1. LYGODIUM Swartz. CLIMBING FERN.

1. Lygodium palmatum (Bernh.) Swartz.

Wet thickets and borders of low woods; several restricted localities, Riverdale
Swamp, vicinity of Suitland, Lanham, Arundel; probably of commoner occurrence.
Sept.Oct. N. Eng. to Fla. and Tenn.

4, POLYPODIACEAE. Fern Family.

Leaves obviously of two kinds, the fertile ones with narrow, more or less altered

divisions.
Fertile blades with linear simple flat greenish pinne, the large narrow sori arranged
in a conspicuous double line................-...-.-2------- 1. LORINSERIA.

Fertile blades not at all leaflike, the spore-bearing parts greatly contracted, berry-
like or necklace-like, brownish, with the sori wholly concealed.
Sterile blades pinnately parted or divided, with netted veins; fertile parts a
close berry-like cluster..........-..2...2 2200. - eee ee eee eee ee 2. ONOCLEA,
Sterile blades pinnate, the pinns: very deeply pinnatifid, with free veins; fertile

parts much simpler (once pinnate only), coarser, necklace-like.
3. PTERETIS.

Leaves uniform, the fertile ones not differing essentially in form from the sterile ones,

Sporangia borne at the edge of the lobes or segments, either in definite clusters (sori)
or as a continuous marginal line.

Rootstocks widely creeping underground, slender, naked or hairy, devoid of

scales. .

Blades erect, narrowly triangular-lanceolate, finely dissected; sporangia borne

in minute cuplike indusia at the ends of the veins. ...4. DENNSTEDTIA.

Blades nearly horizontal, broadly triangular, coarse; sporangia borne in a

broad line within the margin, protected by a delicate continuous indusium.

5. PTERIDIUM.

Rootstocks erect or short-creeping, with a copious covering of imbricate scales.

Blades delicate, the very numerous minute beadlike divisions glandular and

freely clothed with pale rusty jointed hairs........... 6. CHEILANTHES.

Blades coarser, the pinnules or segments comparatively few and large, flat,
neither glandular nor hairy.

Sporangia borne in a long continuous line, partly protected at first by the
slightly revolute unchanged margin of the simple segment, eventually
spreading, the margin becoming flat.....................-7, PELLAEA,

Sporangia borne in narrowly oblong individual sori, several to each cleft or
lobed segment, seated on the inner side of the sharply reflexed modified

tip of the lobe...........--- 222 - cee e eee ee ee ee eee eee ee 8. ADIANTUM.
Sporangia borne on the back of the segments in definite sori, distinctly apart from
the margin.

Blades simple, entire. Leaves 10-30 cm. long, the blades narrow, long-tapering
from a cordate base, rooting at the tip, thus giving rise to new plants.
9. CAMPTOSORUS.

54 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Blades once to several times pinnatifid or pinnate.

Margins of pinnze with numerous slender bristle-like teeth; sori confined to
the contracted uppermost pinnz of some of the blades, large, contiguous,
nearly covering the under surface............-...-. 10. POLYSTICHUM.

Margins not with bristle-tipped teeth; sori not confined to tip of blade.

Veins partly united to form a single series of narrow meshes along the mid-
veins of the pinn and segments, the sori confined to these.
11. ANCHISTEA.
Veins all free.
Sori oblong to linear.
Plants mostly small, 5-30 cm. high, the leaves evergreen; sori straight
or slightly curved 22.22... 2... ...0. 00002. e ee eee 12. ASPLENIUM.
Plants larger, mostly 50-100 cm. high, the leaves herbaceous, winter-
killing; sori curved, often crossing the veinlet and recurved upon it.
13. ATHYRIUM.
Sori roundish.
Blades cut nearly to the midrib, the segments entire or faintly toothed.
14, POLYPODIUM.
Blades 1-3 times pinnate, the primary pinne sessile or stalked.
Indusia attached beneath the sporangia and at first inclosing them,
at length splitting into several spreading lobes. ...15. WOODSIA.
Indusia attached laterally (wanting in one species of Dryopteris),
thrust to one side by the ripening sporangia.

Indusia hood-shaped, attached by the broad base, early pushed
back by the developing sporangia and partly concealed by
them, withering..................0..002.02.002202000- 16, FILIX.

Indusia, if present (lacking in D. heragonoptera), reniform or
rounded-reniform, flat or convex, attached at the sinus, usually
persistent............-22222.22220.000022.. 17. DRYOPTERIS.

.1. LORINSERIA Presl.

1. Lorinseria areolata (L.) Presl. CHAIN FERN.
Swamps and other low, permanently moist, shaded situations; not uncommon.
Late summer. Me. to the Gulf states; also in Mich. (Woodwardia angustifolia J. E.
Smith; W. areolata Moore.)
2. ONOCLEA L.
1. Onoclea sensibilis L. SENSITIVE FERN.
Moist situations generally; abundant. Late summer. Newf. to the Gulf states,

westward.
8. PTERETIS Raf.

1. Pteretis nodulosa (Michx.) Nieuwland. OsTRICH FERN.

Shaded alluvial flood plain of the Potomac, on both sides above Cabin John; rare.
First of Sept. N.S. to Va., westward. (Struthiopteris germanica and Matteuccia stru-
thiopteris of American authors.)

4. DENNSTEDTIA Bernh.

1. Dennstedtia punctilobula (Michx.) Moore. HAY-SCENTED FERN.
Low woods or moist banks; fairly common, Aug. N.S. to Ga., westward. (Dick-
sonia pilosiuscula Willd.)
5. PTERIDIUM Scop.

1. Pteridium latiusculum (Desv.) Maxon. BRAKE. BRACKEN.

Sunny sandy slopes, low thin woods, or old fields, and acid soil situations generally ;
abundant. Midsummer. Eastern N. Amer. (Pteris aquilina and Pteridium aquilinum
of most authors, in part.)

FLORA OF THE DISTRICT OF COLUMBIA. 55

6. CHEILANTHES Swartz. Lip-FERN.

1. Cheilanthes lanosa (Michx.) Watt.
Earthy crevices of cliffs or rocky bluffs; rare; vicinity of Great Falls (both sides of the
river) and near Chain Bridge. Summer. Eastern U.S. (C. vestita Swartz.)

7. PELLAEA Link.

1. Pellaea atropurpurea (L.) Link. CLIFF-BRAKE.

Crevices of dry sunny cliffs or on walls, preferring limestone; several scattered
stations, abundant in only one or two localities. Summer. N. Eng. to Minn., the
Mexican border, and Fla.

8. ADIANTUM L. MarpeEnnair.
1, Adiantum pedatum L.
Rich, well-drained, rocky, deciduous woods and shaded hillsides; common. Sum-
mer. Most of temperate N. Amer., the western form differing subsvecifirallv.

9. CAMPTOSORUS Link.

1, Camptosorus rhizophyllus (L.) Link. WALKING FERN.
Shaded mossy rocks in cool situations; several localities along the Potomac, prin-
cipally above Cabin John; also at Laurel; rare. Que. to Ga., westward.

10. POLYSTICHUM Roth.

1. Polystichum acrostichoides (Michx.) Schott. CHRISTMAS FERN.
Moist woods and cool shady banks; abundant. About June first. Eastern N. Amer.
(Aspidium acrostichoides Swartz.)
A colony is shown in plate 12.

11. ANCHISTEA Presl.

1. Anchistea virginica (L.) Presl. CHAIN FERN.
Swamps; infrequent, the known localities all in the eastern part of the range. Late
summer. Eastern N. Amer. (Woodwardia virginica J. E. Smith.)

12. ASPLENIUM L. SpieEeNwort.

Blades pinnatifid, or pinnate only near the base, the apex slender, long-attenuate.
Stipe brown below, green above; rachis green.............- 1. A. pinnatifidum .
Stipe and rachis dark purplish brown....................--+---- 2. A. ebenoides.

Blades 1-3 times pinnate, the apex not lony-attenuate.

Stipes and rachises reddish or purplish brown throughout; blades linear, once pin-

nate only.
Fertile leaves rigidly erect, 20-40 cm. long; sterile leaves short, spreading; seg-
ments more or less auricled...................--.------ 3. A. platyneuron.
Fertile and sterile leaves alike, all spreading, much narrower, 7-20 cm. long; seg-
ments not auricled.............--..----------- eee ee eee 4. A. trichomanes.
Stipes green from a dark brown base; rachises green; blades 2 or 3 times pinnate or
pinnatifid, more or less triangular..:.............-2-2---.-- 5. A. montanum.

1, Asplenium pinnatifidum Nutt.
Crevices and earth pockets of shaded cliffs; Virginia shore of the Potomac severa]
miles below Great Falls; very rare. Summer, Conn. to Ga., westward.
2, Asplenium ebenoides R. R. Scott. Scotr’s SPLEENWORT.
Crevices of shaded rocks; two records, Plummers Island and Virginia shore of the
Potomac near Little Falls. Summer. Vt. to Va., Mo., and Ala.; abundant only in the
last state, where it is self-perpetuating.

56 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Demonstrated to be a hybrid between Camptosorus rhizophyllus and Asplenium
platyneuron.
3, Asplenium platyneuron (L.) Oakes. EBONY SPLEENWORT.
Grassy or rocky banks and partially shaded situations generally; abundant, Mid-
summer. N. Eng. to Colo., southward to the Gulf states. (A. ebeneum Ait.)
4, Asplenium trichomanes L. MAIDENHAIR SPLEENWORT. DWARF SPLEENWORT.
Crevices of cool shaded cliffs; upper Potomac region chiefly; infrequent. Summer.
Temperate N. Amer., north of Mex.; also in Eur. and Asia.
5. Asplenium montanum Willd. MOUNTAIN SPLEENWORT.
Crevices of dryish cliffs; a single station, above Great Falls on the Virginia side of
river; very rare. Conn. to Ohio, southward,

13. ATHYRIUM Roth.

Pinne narrowly linear, entire or lightly crenulate................ 1. A. pycnocarpon,
Pinne lanceolate, pinnatifid or pinnate.
Segments fully adnate, lightly crenate-serrate............ 2. A. thelypteroides.
Segments or pinnules mostly sessile, deeply serrate or pinnately incised with
toothed lobes. .......... 2. cece eee cece cece ee ceeeees 8. A. asplenioides.

1, Athyrium pycnocarpon (Spreng.) Tidestrom.

Moist cool woods and shaded alluvial banks; not common; several localities in
Rock Creek Park and along the Potomac. Summer. Que. to Ga., westward. (As-
plenium angustifolium Michx.)

2. Athyrium thelypteroides (Michx.) Desv. SILVERY SPLEENWORT.

Moist rich woods, chiéfly in alluvial situations; fairly common, especially along the
upper Potomac. Summer. Eastern N. Amer. (Asplenium thelypteroides Michx.;
Asplenium acrostichoides Swartz. )

8. Athyrium asplenioides (Michx.) Desv. LADY FERN.

Low woods and moist.thickets; abundant. Summer. Eastern U. 8. (Asplenium
Jilix-foemina in part of American writers, not L.)

14. POLYPODIUM L.

Plants grayish beneath, the lower surface of the blades very densely covered with
pale dark-centered peltate scales; sori small, sunken....... 1. P. polypodioides.
Plants green, the blades devoid of scales; sori superficial............... 2. P. vulgare.

1. Polypodium polypodioides (L.) Hitche. Gray rotypopy. REsuRRECTION FERN.
Flat mossy rocks or tree trunks; gorge of the Potomac below Great Falls, Maryland

side, the only locality. Summer. Pa. to Iowa, southward to the Gulf states and

trop. Amer. generally. (P. incanwm Swartz.)

2. Polypodium vulgare L. Potyropy.
Rocks or rocky banks; common along the upper Potomac and found in a few other

localities. Summer. Eastern N, Amer.; also in Eur,

15, WOODSIA R, Br,

1, Woodsia obtusa (Spreng.) Torr.
Rocky banks and shaded cliffs; common, especially along the upper Potomac and
the canal. Summer. Eastern N. Amer.

16. FILIX Adans, BLappER FERN.

Blades very narrowly triangular-lanceolate, the apex long-tapering to a slender tip,
usually bearing numerous fleshy bulblets beneath............ 1. F. bulbifera,
Blades broadly lanceolate, slightly narrowed at the base, the apex short-pointed;
bulblets wanting...........0.. 000 cece cece cece cece cee eee 2. F. fragilis.

FLORA OF THE DISTRICT OF COLUMBIA. 57

1. Filix bulbifera (L.) Underw.

Shaded talus of cliffs: Virginia side of the Potomac in the region opposite Cabin
John; very rare. Newf. to northern Ga., westward. (Cystopteris bulbifera Bernh.)
2, Filix fragilis (L.) Underw. BRITTLE FERN.

Shaded alluvial flats, rocky slopes, and moist woods; abundant in many localities,
principally along the Potomac; common. Summer. N. Amer. generally; nearly
cosmopolitan. (Cystopteris fragilis Bernh.)

17. DRYOPTERIS Adans.

Indusia wanting; blades triangular, usually broader than long; pinne adnate to the
irregularly winged rachis. ......--------2+-+ees- ee eee eres 1. D. hexagonoptera.
Indusia present; blades linear-lanceolate or narrowly oblong to ovate, much longer
than broad; pinne sessile, the rachis not winged.
Rootstocks very slender, widely creeping, nearly naked; fronds winter-killing,
membranous; veins simple or once forked.
Lower pinne gradually decreasing in size, the lowest ones minute,
2. D. noveboracensis.
Lower pinne scarcely smaller than those above.
Fertile veins simple.........------2eeee eee e eee e eee eceeee 3. D. simulata.
Fertile veins once forked........-----..22- ee eee cere eeeeee 4. D. thelypteris.
Rootstocks stout, short-creeping to erect, conspicuously scaly; fronds mostly ever-
green, of firm texture; veins mostly 2 or more times forked.
Blades leathery; sori very much nearer the margins than the midribs of the seg-
MONS... - ence ee ence eee cece eee eee eee ence eee eeeerrces 5. D. marginalis.
Blades firm, but not thick and leathery; sori about midway from midrib to margin
or nearer the midrib.
Fertile leaves very rigidly erect, tall and slender, long-stalked, the blades
linear-oblong to narrowly lanceolate; sterile leaves short, spreading.
- 6. D. cristata.
Fertile and sterile leaves mostly ascending or spreading, the blades much
broader, mostly oblong to ovate.
Basal scales thick, shining, dark chestnut-colored........-- 7. D. goldiana.
Basal scales thin, membranous, dull light brown.
Pinne deeply pinnatifid only, the few coarse lobes or divisions all adnate
and distinctly joined, the wing very broad toward the tip.
8. D. clintoniana.
Pinne essentially pinnate, at least the basal segments free, the others
mostly constricted, joined by a faint wing or not.
Pinnules oblong to oblong-ovate, obtuse or at most acutish.9. D. boottii.
Pinnules mostly oblong-lanceolate, acute.

Pinnz oblique to the rachis, the basal ones distant, broadly triangular;
pinnules obliquely incised, the lobes with curved spinelike teeth;
indusia without glands....-..-.--.---------+++- 10. D. spinulosa.

Pinne at right angles to the rachis, the basal ones ovate, strongly
unequal-sided; pinnules pinnately divided, the segments with
spreading teeth; indusia glandular.........--- 11. D. intermedia.

1. Dryopteris hexagonoptera (Michx.) C. Chr. BEECH FERN.
Dryish or well-drained open deciduous woods; abundant. Midsummer. Eastern

N, Amer. (Phegopteris hexagonoptera Fée.)

2. Dryopteris noveboracensis (L.) A. Gray. New YORK FERN.
Moist low woods and thickets; abundant. July. Eastern N. Amer, (Aspidium

noveboracense Swartz.)

58 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

3. Dryopteris simulata Davenp. MASSACHUSETTS FERN.
Woodland swamps; Hollywood Swamp and near Suitland; reported also from one or
two other stations. Late summer. Me. to central N. Y. and Md.
4. Dryopteris thelypteris (L.) A. Gray. MARSH FERN.
Marshes and low thickets, especially along streams; common. Midsummer.
Kastern N. Amer. (Aspidium thelypteris Swartz.) .
5. Dryopteris marginalis (L.) A. Gray. MARGINAL SHIELD-FERN.
Rocky hillsides in rich woods; common, chiefly along the upper Potomac, July.
N. 8. to Br. Col., south to Ga. and Okla. (Aspidium marginale Swartz.)
6. Dryopteris cristata (L.) A. Gray.
Swamps and moist or boggy woods; common. July. Newf. to Va. and Ark., north-
westward. (Aspidiwm cristatum Swartz; A, filix-mas of Ward’s Flora.)
7. Dryopteris goldiana (Hook.) A. Gray. GOLDIE’S FERN.
Rich deciduous woods; several stations along the upper Potomac, both sides; rare.
N. Br. to Minn. and N. 0. (Aspidiwm goldianuwm Hook.)
8. Dryopteris clintoniana (D. C. Eaton) Dowell. CLINTON’S FERN.
Boggy woods; Lincolnia; very rare. Me. to Wis., south to N. C. (D. cristata
clintoniana D. C. Eaton.) ;
9. Dryopteris boottii (Tuckerm.) Underw. Boort’s FERN.
Moist wooded ravines; several localities, mostly in runs of the upper Potomac.
Summer. N.S. to Minn. and Va. (Aspidium boottii Tuckerm.)
Now usually regarded as a hybrid between D. cristata and D. intermedia.
10. Dryopteris spinulosa (Muell.) Kuntze.
Rich low woods; common throughout the range. Summer, Newf. to Va., north-
westward. (Aspidium spinulosum Muell.)
11. Dryopteris intermedia (Willd.) A. Gray. Woop FERN,
Moist or dryish woods; fairly common, Summer. Newf. to Wis., south to N. C.
(Aspidium spinulosum intermedium D. C. Eaton.)
Besides Dryopteris boottii the following hybrids have been collected:
DRYOPTERIS CRISTATA X MARGINALIS Davenp. Two collections, near Great Falls,
Va. (Dowell).
DRYOPTERIS GOLDIANA X MARGINALIS Dowell. Woods near Kensington (Dowell).

Marsilea quadrifolia L. was accidentally introduced in 1880 at Government Fish
Ponds, since filled; it has perhaps escaped to the river. Native of Eur. and Asia ;
possibly native at Bantam Lake, Conn., thence widely introduced from Mass. to Md.

5. EQUISETACEAE. Horsetail Family.
1. EQUISETUM L.

Stems annual and of two kinds, the fertile appearing in spring and early withering,

the sterile ones with whorls of numerous branches................ 1. E. arvense.
Stems perennial, evergreen, alike, without whorls of branches.......2. E. praealtum.
1. Equisetum arvense L. HOrseEvTAIL.

Sandy or alluvial soil; common. Early spring. Temperate N. Amer. generally,
north of Mex.; also in Eur. and Asia,
2. Equisetum praealtum Raf. ScOURING-RUSH.
Alluvial banks of the Potomac and tributary streams ; occasional patches, but not
‘common. U.S. generally. (£. robustum A. Br.; E. hyemale of Ward’s Flora.)

FLORA OF THE DISTRICT OF COLUMBIA. 59

6. LYCOPODIACEAE. Club-moss Family.
1. LYCOPODIUM L. Cius-Moss,

Spore cases borne in zones along the stem, in the axils of ordinary leaves,
1. L. lucidulum.,
Spore cases borne in terminal conelike spikes.
Plants without leafy aerial branches, the long-stalked fertile spikes arising
directly from the prostrate creeping leafy stem.
Stems short-creeping, the leaves of two kinds, arranged in 4 rows, spreading;
stalks of the fertile spikes very slender, with minute scattered bracts.
2. L. carolinianum.
Stems wide-creeping, the numerous leaves alike, slender, curved upward;
stalks of fertile spikes stout, with numerous slender incurved overlapping
leaves............c ce ee eee ee eee eee eee eee eeeeeeees 8. L. adpressum.
Plants with numerous erect or ascending leafy branches, the spikes terminal on
some of these.
Leaves of the ultimate branches very slender, spreading, arranged in 6 or more
rows.
Stems running horizontally deep in the ground, the few distant aerial
branches upright and treelike, with numerous bushy branches; leaves in
6 or 8 OWS... 2 ee eee eee eee ee eee teen ceeeee 4, L. obscurum.
Stems prostrate, creeping many feet over the ground, branching horizontally,
with numerous very leafy upright branches; leaves in many rows.
5. L. clavatum.
Leaves of the ultimate branches minute, mostly imbricate, adnate and decur-
rent, arranged in 4 rows.
Ultimate leafy branches strongly flattened; leaves of the under row smrller
than the others and of different form....6. L. complanatum flabelliforme.
Ultimate leafy branches much narrower, appearing less flat; leaves of the
under row slightly smaller than the others but of similar form,
7. L. tristachyum.
1. Lycopodium lucidulum Michx.
Cold damp woods and springy wooded banks, sometimes in beds of sphagnum;
infrequent, though of general distribution. Eastern N. Amer.
2. Lycopodium carolinianum L.
Cold sphagnum bog of white gravel and sand; a single locality known, Prince Georges
County. N.J. to the Gulf states; a Coastal Plain plant.
3. Lycopodium adpressum (Chapm.) Lloyd & Underw.
Bogs and low open fields, often in running water; abundant at several localities east
of Washington. N. Y. to the Gulf states; mainly coastal.
4. Lycopodium obscurum L. GROUND PINE.
Moist woods and thickets; several scattered localities; not very common. Newf. to
Alaska, south to Ga.; also in Asia. (L. dencroideum Michx.)
5. Lycopodium clavatum L. RUNNING PINE.
Moist thickets and pine woods; apparently rare; Lanham; Sandy Springs; Merrifield.
Most of N. Amer.; also in Eur. and Asia,
6. Lycopodium complanatum flabelliforme Fernald. CHRISTMAS GREEN.
Damp woods and thickets; fairly common. N. 8. to Minn., south to Va. (Typica]
L. complanatum ranges from Me. northward.)
7. Lycopodium tristachyum Pursh. CHRISTMAS GREEN. GROUND PINE,
Low damp woods and thickets; not uncommon. Eastern U. 8. (ZL. chamaecyparis-
sus A. Br.; L. complanatum sabinaefolium of Ward’s Flora.)

60 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

7, SELAGINELLACEAE, Selaginella Family,
1, SELAGINELLA Beauv.

Leaves very numerous, alike, appressed, widely overlapping, many-ranked, linear-

lanceolate, ending in a slender whitish awn.................... 1, S. rupestris.
Leaves few, of 2 kinds, 4-ranked, spreading in 2 planes, ovate, acute or cuspidate,
2. S. apoda.

1. Selaginella rupestris (L.) Spring.

Exposed rocky bluffs; found only in vicinity of Great Falls, both sides of the river,
Ont. and eastern U.S.
2. Selaginella apoda (L.) Fernald.

Low moist situations, usually in partial shade; common. Me. to the Gulf states,
westward. (8. apus Spring.)

8. ISOETACEAE. Quillwort Family.
1. ISOETES L. Qumtworr.

Leaves 50-100, erect, 30-60 cm. long, with bast bundles....1. I. engelmanni valida.
Leaves 10-30, spreading or recurved, 3-25 cm. long, without bast bundles.
2. I. saccharata.

1. Isoetes engelmanni valida Engelm.

Temporary pools among rocks; Virginia shore of the Potomac, between Sandy Land-
ing and Great Falls; rare. N.J. to Va.
2, Isoetes saccharata Engelm.

Shallow water between tides, on gravel and sand; banks of the Potomac at Fourmile
Run, Hunting Creek, and Mount Vernon; not uncommon, Mass. to Va.

Extremely variable, several forms having been described.

9. PINACEAE, Pine Family,

Leaves scalelike or awl-shaped, opposite....... we cee eee eee ee eens 4. JUNIPERUS.
Leaves linear, needle-like.
Leaves in fascicles..............2....22000. eee errr 1. PINUS,

Leaves solitary.
Leaves stiff, about 10 mm. long, obtuse, persistent, dark green above, pale
beneath; cones oblong, 2 cm. long or more, the scales rounded...2. TSUGA.
Leaves slender, about 15 mm. long, acute, deciduous, light green on both faces;
cones globose or nearly so, the scales thick, woody......... 3. TAXODIUM,

1. PINUS L. Prine.

Leaves 5 in a fascicle; cones more than 9 cm. long, maturing the first year, the scales
without bristles. ........... 0.0.2.2 e cece cece ccc ccc cececee 1. P. strobus.
Leaves 2 or 3in a fascicle; cones less than 9 cm. long, maturing the second year, each
scale bearing a bristle near the apex.
Leaves 3 in a fascicle.
Leaves 7-12 cm. long; cones ovoid, 3.5-7 cm. long................-. 2. P. rigida.
Leaves 15-24 cm. long; cones oblong, 7-12 cm. long.......2....2..06. 3. P. taeda.
Leaves 2 in a fascicle.
Leaves slender, about 1 mm. in diameter, 6 cm. long or more..... 4, P, echinata.
Leaves stout, about 2 mm. in diameter and 4 cm. long.
Cone scales tipped with a slender straight fragile prickle......5. P. virginiana.
Cone scales tipped with a thick curved woody persistent prickle.
6. P. pungens.

FLORA OF THE DISTRICT OF COLUMBIA. 61

1. Pinus strobus L. WHITE PINE.
Sparingly on high ground toward Rockville; also reported from Turkey Run, Barnes-
ville, and Occoquan. Northern states, southward in the mountains to Ga. Also in
cultivation.
Pinus excelsa Wall., the Himalayan pine, is frequently cultivated. It is a hand-
some tree similar to P. strobus, but with leaves 15-20 cm. long.
2. Pinus rigida Mill. PircH PINE.
Sandy soil, scattered among Pinus virginiana. Eastern N. Amer.

3. Pinus taeda L. LoBLOLLY PINE.
Found sparingly near our eastern limit; a few trees near Leland Station above

Upper Marlboro; common along the Patuxent near the bay. A handsome tree,

characteristic of the Coastal Plain from southern N. J. to Tex.

4, Pinus echinata Mill. YELLOW PINE.

Sparingly among Pinus virginiana in the southern counties of Maryland; west
of Mount Vernon. Eastern U.S. (P. mitis Michx.)

5. Pinus virginiana Mill. ScRUB PINE.

Our characteristic pine, forming forests in sandy soil. Eastern U.S. (P. tnops
Ait.)

6. Pinus pungens Lamb. TABLE-MOUNTAIN PINE.

A few treesin Rock Creek Park and on the bluffs of the Virginia shore of the Potomac
above Cabin John. In the mountains, particularly along the ridges, from western
N. J. to Ga.

Pinus sylvestris L., the Scotch fir, is common in cultivation. It is readily distin-
guished in its young state from Pinus virginiana by its bluish green young leaves
and by the absence of bloom on its branchlets, a character conspicuous in our
native tree. In America this tree is known under the name Scotch pine, though
the European vernacular name is fir, which is applied properly to Pinus sylvestris and
not to species of Abies.

Pinus austriaca Hoess, the Austrian pine, is extensively cultivated. It is readily
recognized by its stiff dark green leaves, 12-16 cm. long, which are marked by 10 or
11 resin ducts in the parenchyma.

2, TSUGA Carr.

1. Tsuga canadensis (L.) Carr. HEMLOCK.
Virginia shore of the Potomac above Cabin John; abundant at Occoquan. Northern
states, south to Va.

3, TAXODIUM L. C. Rich.

1, Taxodium distichum (L.) L. C. Rich. BALD CYPRESS.
Swamps and along rivers; south of Bowie; near Marshall Hall. Southern states,
north to N. J.

4. JUNIPERUS L. JUNIPER.

1, Juniperus virginiana L. RED CEDAR.

Common along the bluffs of the Potomac, in fields, and along roads; often planted.
Eastern N. Amer.

The leaves are of 2 kinds, scalelike on the mature trees and subulate on the young
growth.

Juniperus communis L., the juniper, cultivated in this region but native farther
north, is distinguished by its verticillate subulate leaves, 10 mm. long or more.

62 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

10, TYPHACEAE. Cat-tail Family.
1.TYPHA L. Car-tal.

Staminate and pistillate portions of the spike distant; leaves 5 mm. wide.

1. T. angustifolia.
Staminate and pistillate portions of the spike contiguous; leaves 10 mm. wide.

2. T. latifolia.

1. Typha angustifolia L.
Marshes and wet places, forming colonies. Eur., Asia, and N. Amer, north of Mex.
2. Typha latifolia L.

Marshes and wet places, forming colonies. Eur., Asia, and N. Amer.

11, SPARGANIACEAE. Bur-reed Family.

1. SPARGANIUM L. Bur-reep.

Fertile flowers sessile; fruit broadly obovoid...............e.0-. 1. S. eurycarpum.
Fertile flowers short-pediceled; fruit fusiform.
Inflorescence simple.............0.. ccc cece ceeccucccecceeceese 2. S. americanum,
Inflorescence with 1 or 2 weak branches from lower axils.
- 2a. S. americanum androcladum.

1. Sparganium eurycarpum Engelm,

Frequent in swamps and marshy margins of streams. Fr, July-Aug. Widely dis-
tributed in N, Amer.
2. Sparganium americanum Nutt.

Frequent in the same situations as the last, but usually in shallower water. June-
July; fr. Sept. Eastern N. Amer. and Asia.
2a. Sparganium americanum androcladum (Engelm.) Fern. & Eames.

Habitat and range same as for the species, (8. androcladum jMorong; S. simplex
androcladum Engelm.)

12. POTAMOGETONACEAE. Pondweed Family.

Leaves alternate; fruit subglobose, short-beaked; flowers perfect.
1. POTAMOGETON.
Leaves opposite; fruit oblong, long-heaked; flowers monoecious.
2. ZANNICHELLIA.
1. POTAMOGETON L. Ponpween.

Leaves of two sorts, the thicker floating ones with a dilated petioled blade, different
in form from the thinner submersed ones,
Submersed leaves less than 2 mm. wide.............-..--.-- 10. P. diversifolius .
Submersed leaves more than 2 mm. wide.
Submersed leaves linear, with a broad, coarsely cellular-reticulate space each
side of the midrib...... 2.2 eee ccc cece ccc ececcece 1. P. epihydrus.
Submersed leaves broader than linear, not differentially reticulate.
Floating leaves 30-50-veined; submersed leaves large, wide, often much
TECUIVEd . 2. oe ee ce ee cee cece ccc e cece cnc cccceccees 3. P. amplifolius ,
Floating leaves fewer-veined; submersed leaves narrowly lanceolate.
2. P. americanus.

FLORA OF THE “ISTRICT OF COLUMBIA. 63

Leaves all alike, submersed.
Leaves lanceolate or broader.

Leaves cordate-clasping..... 2.22.2... 200 e cece e cece eee ee eeee 5. P. perfoliatus.
Leaves sessile or short-petioled, not clasping.
Leaves oblong, sessile, minutely serrate..........-...----..-..- 6. P. crispus.
Leaves oval or lanceolate, short-petioled, the margin often crisped but not
minutely serrate. ..........0.0. cece ee eee eee ee ee eee eee eee 4. P. lucens.

Leaves linear to setaceous.
Leaves 2 mm. wide or more, with a broad, coarsely cellular-reticulate space each
side of the midrib...............2.2 22020022 e ee eee eee eee 1. P. epihydrus.
Leaves narrower or not differentially reticulated.
Stipules united with the leaves.

Leaves threadlike; fruitabundant.................-...--- 11. P. pectinatus.

Leaves 4-8 mm. wide; plants rarely fruiting. ............-- 12. P. robbinsii.
Stipules free from the leaves.

Stems much flattened; leaves 2-4 mm. wide.........-.--- 7. P. zosteraefolius.

Stems little or not at all flattened; leaves less than 2 mm. wide. Spikes
usually few-flowered.

Plants with translucent wartlike glands on each side of the stem at the

insertion of the leaves; fruiting spikes long-stalked. .. . - . 8. P. pusillus.
Plants without such glands; fruiting spikes short-stalked.

Spikes borne at the endsof the branchlets; fruits plump. .9. P. foliosus.

Spikes borne in the leaf axils; fruits appearing as if coiled, hollowed out

on the sides........-.--.-- wee e ee ee eee cece ee eee 10. P. diversifolius.

1. Potamogeton epihydrus Raf.

Occasional in pools or at margins of slow streams. June-July. Widely distributed
in N. Amer. (P. claytonii Tuckerm.; P. nuttallii Schlecht. & Cham.)

2. Potamogeton americanus Schlecht. & Cham.

Common in streams and the canal. Aug. Widely distributed in N. Amer. (P.
lonchites Tuckerm.)

3. Potamogeton amplifolius Tuckerm.

Common in mouths of large creeks below Washington. Fr. June until fall. Eastern
and northern N. Amer.

4. Potamogeton lucens L.

One specimen collected by Ward near Custis Spring. N. Amer. and Eurasia.

5. Potamogeton perfoliatus L. -REDHEAD GRASS.
Common in the river and creek mouths below Washington. June-Aug. N. Amer.

and Eurasia.

6. Potamogeton crispus L.

Frequent in the canal, and in the Potomac and its tributaries below Washington.

Eastern U. 8.; also in Eur.

Propagates mainly by modified branchlets.

7. Potamogeton zosteraefolius Schumacher.

Common in mouths of large creeks below Washington. N. Amer. and Eurasia.
Fruit rare; propagation chiefly by winter buds.

8. Potamogeton pusillus L.
River and creek mouths below Washington; apparently scarce. Almost cosmopolitan.
Propagates extensively by winter buds.

9. Potamogeton foliosus Raf.

Frequent in pools and slow streams. July. Nearctic Amer. (P. pauciflorus

Pursh.)

64 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

10. Potamogeton diversifolius Raf.
Common in shallow pools and at margins of quiet waters; rock pools at Great Falls;
edge of canal. Fr. July-Aug. Nearly throughout the U.S. (P. hybridus Michx.)
The characters supposed to distinguish P. dimorphus Raf. from P. diversifolius are
neither prominent, constant, nor important. Specimens possessing the diagnostic
points of both forms are readily found.
11, Potamogeton pectinatus L. SAGO PONDWEED.
Abundant in quiet waters. Fr. July to fall. Cosmopolitan.
Notable for its abundant tubers which are eagerly sought by waterfowl.
12. Potamogeton robbinsii Oakes.
Common in the mouths of large creeks below Washington. Northern U. 8.
Rarely fruits.
Potamogeton natans L.., recorded by Ward from the Eastern Branch, is not repre-
sented by specimens.

2. ZANNICHELLIA L. HorNep PONDWEED.

1. Zannichellia palustris L.
Occasional along the edge of the river and canal. Fr. July-Sept. Cosmopolitan.

18. NAIADACEAE.
1. NAIAS L. Busuy PONDWEED.

Basal auricles of the leaves rounded, toothed on the even margin; leaves linear, the
teeth frequent.

Stem slender, many-leaved, usually much branched................ 1. N. flexilis.
Stem stout, few-leaved, sparsely branched, elongate... ... la. N. flexilis robusta.
Basal auricles of the leaves pectinate, toothed on the irregular divisions; leaves
threadlike, the teeth sparse................22.0.0. 0202 ee eee 2. N. gracillima,

1. Naias flexilis (Willd.) Rostk. & Schmidt.
Abundant in the canal and other quiet waters. Fr. July. Northern Hemisphere.
Entire process of fertilization takes place under water.
la. Naias flexilis robusta Morong.
Found with the species.
2. Naias gracillima (A. Br.) Magnus.
Abundant in a pool at Widewater. Northeastern U.S.

14, ALISMACEAE. Water plantain Family.

Flowers 2-2.5 mm. wide, in large panicles; achenes borne in a single whorl; leaves

ovate, cordate. Flowers all perfect...........2.....---2--ee eee eee 1, ALISMA.

Flowers 4-15 mm. wide, usually in whorls of 3 (sometimes 2 in Lophotocarpus);

achenes borne in a dense head; leaves arrow-shaped, or else acute at the base.
Pedicels very stout; lower flowers of the inflorescence perfect.

2. LOPHOTOCARPUS.

Pedicels slender; lower flowers of the inflorescence pistillate....8. SAGITTARIA.

1, ALISMA L.

1. Alisma subcordatum Raf. WATER PLANTAIN.

Shallow water and mud; along the canal, and flats below Chain Bridge; probably
fairly common in similar locations. June-Sept. Eastern U.S. (Listed as A. plan-
tago, A. plantago americanum, and A. plantago-aquatica.)

Echinodorus radicans (Nutt.) Engelm. has been reported by Steele, ‘‘ along a de-
pression in the flats below Chain Bridge, perhaps a dozen specimens, some well devel-
oped, August 1, 1900.”

FLORA OF THE DISTRICT OF COLUMBIA. 65

2..LOPHOTOCARPUS T. Durand.

1. Lophotocarpus calycinus (Engelm.) J. G. Smith.

Apparently rare; collected only by Steele in the ‘‘Eastern Branch below the Navy
Yard, growing in tide mud;” reported as growing “below Alexandria.” Sept.
Southern states, north to Del.

3. SAGITTARIA L. ARROWHEAD.

Leaves linear to elliptic or ovate (plants rarely with one or more hastate leaves in

S. rigida).
Leaves usually 3-10 (sometimes 20) cm. long; filaments glabrous; plants dwarfish.
Beak of the achene erect or nearly s0.....-----------+-+--+: -..1, S. subulata.

Leaves 12-25 cm. long; filaments glandular-pubescent; plants larger.
Bracts acute, 3-6 mm. long, united to the middle or beyond; beak of the achene
horizontal, very short.......---..--------- essere eeeeeeecree 2. S. graminea.
Bracts obtuse, 4-8 mm. long, united at the base or sometimes distinct; beak of the
achene erect or nearly so, about one-fourth the length of the body.
8. S. rigida.

Leaves arrow-shaped.

Lobes of the leaves very narrowly linear (1-3 mm, wide). Beak of the achene erect.
4. S. engelmanniana.

Lobes of the leaves broader (at least 7 mm. and often 90-120 mm. wide),
Bractsand pedicels pubescent. Beak of the achene horizontal. ..5. 8. pubescens.

Bracts and pedicels glabrous.

Fertile pedicels much longer than the broadly triangular, obtuse, acute, or

occasionally acuminate bracts; beak of the achene horizontal.

6. S. latifolia.
Fertile pedicels shorter than the triangular-lanceolate acuminate bracts; beak
of the achene nearly erect.....-.-----------eeee errr ree 7. &. longirostra.

1. Sagittaria subulata (L.) Buchenau.

Tide-water mud along the Potomac and Eastern Branch; common. July-Sept.
N. Y. to Fla. (S. pusilla Nutt.)
2. Sagittaria graminea Michx.

In the same localities as the preceding species. July-Sept. Eastern N. Amer.
3. Sagittaria rigida Pursh.

Swamps and shallow water; probably common throughout the region. July-
Sept. Eastern states, south to Md. (S. heterophylla Pursh.)

4. Sagittaria engelmanniana J. G. Smith.
Collected only by Steele, who says: “‘First collected, in sterile condition only, in

a swampy pasture near Ardwick, Md., September 6, 1809. Two or three fruiting
specimens were found on the water’s edge at Great Falls, October 3, 1899. * * *
Determination confirmed by Mr. J. G. Smith.’”? Mass. to Va.

5. Sagittaria pubescens Muhl.

Common in shallow water, ditches, and swamps. J uly-Sept. Eastern states,
south to Va. (S. latifolia pubescens J. G. Smith.)
6. Sagittaria latifolia Willd.

Common in habitats similar to those given for the preceding species. July-Sept.
General in N. Amer. except the subarctic zone. (S. variabilis Engelm.; S. variabilis
angustifolia A. Gray.)

7, Sagittaria longirostra (Micheli) J. G. Smith.

Collected only by Steele, ‘‘in moderate quantity in the marsh around the mouth

of Oxon Run, opposite Alexandria. August 18, 1900.’’ Southern states, north to N. J.

69289—19——5

66 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

15, VALLISNERIACEAE, Eel-grass Family.

Plants with branching stems, without tubers; leaves ovate-oblong to linear, 0.5-2
cm. long, opposite or whorled; staminate flowers axillary, the sepals and petals
3; pistillate flowers with a 6-parted perianth and a long capillary tube.

1. ANACHARIS.
Plants stemless, stoloniferous, producing winter tubers; leaves linear, grasslike,
d-nerved, 40-150 cm. long, 1-2 cm. wide; staminate flowers numerous on a conic
receptacle, inclosed in a spathe, the perianth 3-parted; pistillate flowers single
on a long scape reaching the surface of the water and coiling spirally during the

maturing of the fruit, the perianth 3-parted, the tube adherent to the ovary.
2. VALLISNERIA.

1. ANAGHARIS L. Rich.

1. Anacharis canadensis (Michx.) Babingt.
WATER-WEED.
Abundant in the Potomac. June—J uly.
Eastern N. Amer. (Elodea canadensis Michx.;
Philotria canadensis Britton.)

2. VALLISNERIA I..

1. Vallisneria spiralis LL.
EEL-GRASS. WILD CELERY.
Abundant in the Potomac and its tributa-
ries. July. Eastern states, south to N.C.

16. POACEAE, Grass Family.

The cultivated grains of the region are
often found growing spontaneously in waste
places, especially in the vicinity of freight
stations and along railways. These are
mentioned under their respective genera,
except corn or maize (Zea mays L.). The
commoner ornamental grasses are: eulalia,
Miscanthus sinensis Anderas.; plume-grass,
Cortaderia argentea (Nees) Stapf, a tall reed,
growing in large clumps, with numerous long
narrow drooping blades, a flower stalk 1-2
F1a, 1—The inflorescence, spikelet, and floret or Meters long, surmounted by a silvery white

a grass (Bromus secalinus). plume 30-60 cm. long; and two species of

Pennisetum, 60-100 cm. high, used as border

plants, P. villosum R. Br., with short broad heads and plumose bristles, and P. rupellii
Steud., the fountain grass, with slender rose-colored spikes tapering at the apex.

The grass flower consists normally of a pistil and 3 stamens contained between 2
small bracts, these being aggregated in spikelets (Fig. 1). The spikelet is made up
of a central axis (rachilla) upon which the bracts are arranged in 2 ranks. The lower-
most pair of bracts (glumes) are without flowers. The succeeding bracts (lemmas)
have flowers and an inner bract (palea) next the rachilla. The lemma, palea, and
flower are together called the floret. If a lemma contains no flower it is called a sterile
lemma. The spikelets may be 1-flowered or several-flowered and are almost always
aggregate in an inflorescence.

\
N

Spikelets with 1 perfect terminal floret (unisexual in Maydeae and in Zizania) and a
sterile or staminate floret below, usually represented by a sterile lemma only;
rachilla articulate below the glumes, the more or less dorsally compressed spikelets

FLORA OF THE DISTRICT OF COLUMBIA. ; 67

falling entire, singly or together with the joints of an articulate rachis or with a
subtending involucre.
Glumes indurate; lemma and palea hyaline; spikelets falling with the joints of
the rachis attached.
Spikelets unisexual, in racemes, the pistillate below, embedded in the indurate
thickened axis, the staminate in pairs above on the same axis, falling

after anthesis. ........-..00-- 2s eee eee eee eee cence ene I. MAYDEAE.
Spikelets all perfect, or with a staminate or neuter one pedicellate at each joint of
the rachis...........---------- eee ee eee ee eee OW. ANDROPOGONEAE.

Glumes membranaceous; fertile lemma and palea indurate; rachis not disjointing
(spikelets falling with the inclosing bur in Cenchrus). First glume sometimes
wanting, the second glume and sterile lemma simulating a pair of glumes.

I. PANICEAE.

Spikelets 1-many-flowered, if 1-flowered no sterile lemma below (2 sterile lemmas

below in Phalarideae, 1-4 sterile lemmas below in Uniola); rachilla usually articu-

late above the glumes, these persistent on the pedicel, or in a few genera articu-
late below the glumes; spikelets laterally compressed.

Glumes obsolete. Spikelets 1-flowered...........-.-------+++--+- IV. ORYZEAE.

Glumes developed or the first rarely obsolete.

Spikelets with a pair of sterile lemmas (reduced to minute scales in Phalaris)
below the one perfect floret, falling attached to it. Panicles narrow.
V. PHALARIDEAE.
Spikelets with no sterile lemmas below the perfect ones (a staminate lower floret
in Arrhenatherum; 1-4 sterile lemmas below the several perfect florets in
Uniola persistent with the glumes).
Inflorescence of solitary, racemose, or digitate spikes or racemes, the spikelets
sessile or only shortly pedicellate.
Spikelets borne on one side of the axis only (1-sided arrangement somewhat
obscure in Gymnopogon and Leptochloa) .....----- VIII. CHLORIDEAE.
Spikelets alternate on opposite sides of the axis........----. X. HORDEAE.
Inflorescence of open or contracted panicles.
’ Spikelets 1-flowered, the rachilla sometimes prolonged behind the palea.
, VI. AGROSTIDEAE.
Spikelets 2-many-flowered.

Glumes usually exceeding the approximate florets or at least the lower;
lemmas awned from the back or from between the teeth of a bifid
apex (glumes about equaling the lower floret and usually awnless in
Sphenopholis)......-----++02+-0e cece e cece cece ee eee VI. AVENEAE.

Glumes shorter than the lowermost floret, the florets not closely approxi-
mate; lemmas awnless or awned from the apex (apex minutely bifid
in Bromus.)

Plants herbaceous....---.--. voce eee ceeeeeteeeeees IX. FESTUCEAE.
Plants woody.......---------++e-++-> cece cece ereee XI. BAMBOSEAE.
Tribe I. MAYDEAE.
A single genus..............2.-- 22-2222 cece eee eee ert eee 1. TRIPSACUM.

Tribe 1. ANDROPOGONEAE.

Spikelets all alike. Plants robust, tall.
Inflorescence a large grayish fan-shaped panicle of slender woolly racemes; rachis
not disarticulating.........-.-.-.-.2..5--0-+ +22 eee eee eee ee 2. MISCANTHUS.
Inflorescence a dense, narrowly ovoid,woolly panicle; rachis disarticulating.
3. ERIANTHUS.
Spikelets of 2 kinds, one sessile and perfect, one pedicellate and staminate or
neuter (rudimentary in Sorghasirum) at each joint of the rachis.
Spikelets in slender, solitary or digitate racemes, these terminal and lateral.
ANDRGON.

68 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Spikelets in panicles, these terminal only,
Sterile spikelets reduced to the plumose pedicel; panicles narrow, golden bronze,
5. SORGHASTRUM.
Sterile spikelets developed, usually staminate; panicles open...... 6. HOLCUS.

Tribe III. PANICEAE.

Spikelets inclosed in globular spiny burs, these racemose. A spreading annual.

. . . 12, CENCHRUS.
Spikelets not inclosed in‘a bur.

Spikelets subtended by 1 to several slender bristles, arranged in a narrow spikelike

panicle...... 2.222... 11. CHAETOCHLOA.
Spikelets not subtended by bristles.

Spikelets subsessile along one side of a slender axis. First glume obsolete or

minute.
Racemes subdigitate; fruit subindurate, with a flat white hyaline margin;
spikelets compressed, biconvex; annuals............ 7. SYNTHERISMA.

Racemes solitary or racemose; fruit indurate, the firm margin inrolled: spike.
lets plano-convex; perennials. First glume obsolete...8. PASPALUM.
Spikelets in open or compact panicles.
Sterile lemma awnless; fruit not pointed; spikelets usually long-pediceled.

9. PANICUM.
Sterile lemma awned or strongly mucronate; fruit pointed; spikelets short-
pediceled, in clusters. Coarse annuals............ 10. ECHINOCHLOA.

Tribe IV. ORYZEAE.

Spikelets unisexual, the pistillate awned, borne on the erect upper branches of a
large panicle, the staminate awnless, pendulous on the spreading lower branches
of the same panicle; large annual marsh grass ...............-.... 13. ZIZANIA.

Spikelets perfect, awnless; low scabrous perennials... .. 14. HOMALOCENCHRUS.

Tribe V. PHALARIDEAE.

Sterile lemmas consisting of minute awnless scales attached at the base of the indurate

fruit; glumes keeled; plants not fragrant...................... 15. PHALARIS.
Sterile lemmas awned, exceeding the fruit; glumes not strongly keeled; plants fra-
grant... 2.2... cece eee eee eee eeee 16. ANTHOXANTHUM.

° _ ‘Tribe VI. AGROSTIDEAE.

Lemmas subindurate, at least firmer than the glumes, awned or sharp-pointed, terete
or subterete, the palea inclosed.
Awn trifid, the lateral divisions sometimes short................. 17. ARISTIDA.
Awn simple.
Glumes 8-10 mm. long; awns 4-7 cm. long, twisted and bent. Panicle loose and
50 02) 18. STIPA.
Glumes not over 6 mm. long, usually much shorter; awns not over 3 cm. long,
not twisted or bent.
Rachilla prolonged behind the palea; glumes minute; lemma 1 cm. long,

terminating in a slender awn 2-3 cm. long...... 20. BRACHYELYTRUM.
Rachilla not prolonged behind the palea; lemma not over 3 mm. long, awned
or awnless........... 0.0.0.0. 00 022 e eee eee 19. MUHLENBERGIA.

Lemma not firmer than the glumes, usually thinner in texture.
Glumes strongly compressed-keeled. Panicle dense, cylindric, spikelike.
Lemma awnless; glumes abruptly aristate, stiffly ciliate on the keel: rachilla
articulate above the glumes................0...........---. 21. PHLEUM.
Lemma with a slender awn from the back; glumes not aristate, the margins con-
nate toward the base, not stiffly ciliate; rachilla articulate below the glumes,
22. ALOPECURUS.

FLORA OF THE DISTRICT OF COLUMBIA. 69

Glumes more or less compressed but not conspicuously flattened and keeled.
Rachilla not prolonged behind the palea. Floret neither stipitate nor with a
hairy callus.

Lemma longer than the glumes or equaling them; palea equaling the lemma or
longer; panicles narrow, more or less included in the sheaths.

23. SPOROBOLUS.

Lemma shorter than the glumes; palea shorter than the lemma or obsolete;
panicles open, exserted..............------------------ 25. AGROSTIS.

Rachilla prolonged behind the palea as a plumose or naked stipe. Lemma with ~
an inconspicuous awn.

Rachilla and callus bearing silky hairs nearly as long as the floret; floret not
stipitate; rachilla articulate above the glumes; awn from below the middle
of the lemma...................-.02-00 ee ee eee 26. CALAMAGROSTIS.

Rachilla and callus naked; floret stipitate; rachilla articulate below the glumes;
awn minute, from just below the tip of the lemma............24. CINNA.

Tribe VII. AVENEAE.

Glumes dissimilar in shape, the first narrow, the second widerabove, about as long as the
first floret; spikelets awnless, articulate below the glumes. .31. SPHENOPHOLIS.
Glumes similar in shape, exceeding the floret; spikelets awned, usually articulate
above the glumes.
Rachilla not prolonged behind the palea; spikelets not over 4 mm. long; delicate
annuals..... 222.222. eee eee cee eee eee eens 28. AIRA.
Rachilla prolonged behind the palea of the uppermost floret; spikelets more than
4mm. long; perennials (except Avena),
Articulation below the glumes; florets 2, dissimilar, the lower awnless, the upper

with a hooklike awn. Plants velvety.................... 27. NOTHOLCUS.
Articulation above the glumes (except in Trisetum); florets similar (except in
Arrhenatherum).

Florets 2, the lower staminate and awned, the upper perfect and awnless.
33. ARRHENATHERUM.
Florets 2 to several, all perfect, awned (except sometimes in Avena),
Awn from between the teeth of the bifid lemma, flat, twisted; spikelets

several-flowered...........--.-----------02-0+------ 34. DANTHONIA.
Awn dorsal, not flattened; lemma often bifid at apex; spikelets 2 or 3-flowered.
Spikelets large, the glumes over 1 cm. long.............-..-- 82. AVENA.

Spikelets less than 1 cm. long.

Lemmas keeled, bidentate; awn arising from above the middle.

: 30. TRISETUM.
Lemmas convex; awn from below the middle..... 29. DESCHAMPSIA.

Tribe VI. CHLORIDEAE.

Spikes digitate or subdigitate. Spikelets awnless.
Spikelets 1-flowered, the spikes slender; astoloniferous perennial...85. CAPRIOLA.
Spikelets several-flowered, the spikes flat, rather broad; an annual..38. ELEUSINE,
Spikes racemose along the axis.

Articulation below the glumes, the compactly crowded spikelets falling entire;
second glume exceeding the single awnless floret. Spikes relatively short and
stout.............. 02 ee eee eee eee 36. SPARTINA.

Articulation above the glumes; glumes shorter than the awned florets.

Spikelets with 1 perfect floret (a rudimentary floret above it), remote and
appressed along a rigid filiform axis, the long slender spikes stiffly spreading
or reflexed; blades firm, short, broad, and spreading. .37. GYMNOPOGON.

Spikelets with several perfect florets; spikes ascending; blades long and lax.

39. LEPTOCHLOA.

70 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Tribe IX. FESTUCEAE.

Plants tall and stout, 2-4 meters high; inflorescence a large plumelike panicle.
40. PHRAGMITES.
Plants low or moderately tall, rarely over 1.5 meters high; inflorescence not plumelike.
Lemmas prominently 3-nerved.
Lemmas villous on the nerves below; panicle large, drooping, viscid.
41. TRIDENS.
Lemmas glabrous; panicles not viscid, sometimes odoriferous.
42. ERAGROSTIS.
Lemmas 5-many-nerved.
Upper florets reduced, the empty lemmas inclosed one within the other, forming
a club-shaped mass, Glumes broad and papery; spikelets in a small panicle,
pendulous on capillary pedicels.............-.......2.-.22--. 43. MELICA.
Upper florets not differing from the lower in shape.
Spikelets with 1-4 sterile lemmas below the fertile ones, these persistent with
the glumes.............. 02.002 e cece cee eee ee eee eee eee eee 44, UNIOLA.
Spikelets with no sterile lemmas below the fertile ones.
Spikelets strongly flattened, subsessile in 1-sided clusters at the ends of long
naked panicle branches, these spreading in anthesis, erect in fruit.
45. DACTYLIS.,
Spikelets neither strongly flattened nor in clusters. .
Lemmas awnless, obtuse or subacute.
Lemmas keeled, the spikelet compressed; nerves rather faint...46. POA.
Lemmas convex, the spikelet turgid or subterete; nerves usually
prominent...............--2.222.--2--220-0--- 47, PANICULARIA.
Lemmas awned or sharp-pointed.
Lemmas rounded on the back, the awn, if present, from the tip.

48. FESTUCA.
Lemmas keeled toward the summit, awned from between 2 minute teeth
(awn very short in B, untoloides)...........-.....-. 49. BROMUS.

Tribe X. HORDEAE.

Spikelets more than one at each node of the rachis, awned.
Spikelets not all alike, the cluster consisting of a sessile perfect spikelet with a
pediceled spikelet reduced to the 2-4 awns on each side...... 54. HORDEUM.
Spikelets all alike.
Glumes well developed; spikelets appressed or ascending, imbricate.

55. ELYMUS.
Glumes obsolete or reduced to small bristles; spikelets remote, horizontally
spreading................ wee eee eee eee tere eee ee eeee 56. HYSTRIX.

Spikelets solitary at each node of the rachis.
First glume (except in the terminal spikelet) wanting; spikelets placed edgewise
to the rachis..............202.0..2 02222 e eee eee eee eee 50. LOLIUM.
First glume present; spikelets placed flatwise to the rachis.
Rachilla disarticulating between the florets; plants perennial.
61. AGROPYRON.
Rachilla disarticulating above the glumes only; plants annual.
Glumes subulate, l-nerved; lemmas ciliate on the keel and exposed margin.
52. SECALE.
Glumes lanceolate, 3-nerved; lemmas not ciliate............ 58. TRITICUM.

Tribe XI. BAMBOSEAE,
A single genus. ...... 06. cece cece cee ee eee ence ee eeee 57. ARUNDINARIA.

FLORA OF THE DISTRICT OF COLUMBIA. 71

1. TRIPSACUM L.

1, Tripsacum dactyloides L. GAMA GRASS.
Low moist or wet ground; abundant in a few localities in the flood plains of the
Potomac and occasional elsewhere. Aug. Southeastern U. S., north to N. Eng.
Growing in large clumps and forming hard mats of thick horizontal rootstocks lying
on or near the surface. This and Zizania palustris are the only native monoecious
grasses of this region.

2. MISCANTHUS Anderss.

1. Miscanthus sinensis Anderss. EULALIA.

Escaped from cultivation and established on wooded hillsides in the vicinity of
Mount Pleasant, Cleveland Park, Chevy Chase, and Forest Glen. Aug.Sept. Native
of Asia.

Cultivated for ornament; growing in large tufts, with numerous narrow blades
60-120 cm. long, and slender upright flower stalks 1-2 meters high, bearing fan-
shaped clusters of woolly racemes 15-30 cm. long. The blades are often variegated
with bands or stripes. Known to gardeners as Hulalia japonica.

3. ERIANTHUS Michx.

1. Erianthus saccharoides Michx.

Wet meadows and swales; occasional in the vicinity of Brightwood and Kenilworth.
Aug.-Oct. Southern states, north to N. J. (£. alopecuroides of Ward’s Flora.)

A striking species, with culms as much as 2 meters tall, bearing a dense feathery
plume 10-20 cm. long. Our form with somewhat more compact panicles has been
described as EH. compactus Nash.

Arthraxon ciliaris cryptatherus Hack. has been found on the Chevy Chase golf
course. Culms creeping; blades ovate-lanceolate, cordate, ciliate at base; racemes
slender, several in a fascicle. Introduced from Japan.

4, ANDROPOGON L.

Racemes borne singly on the few to many branches. (Subgenus Schizachyrium).
1. A. scoparius.
Racemes 2 to several together, digitate or nearly so, the common peduncle often

inclosed in a bractlike sheath or spathe, these sometimes in groups forming a

compound inflorescence.

Pedicellate spikelet staminate, as large as the sessile spikelet; terminal racemes 2
to several, exserted on a naked peduncle, the uppermost sheath inconspicuous,
not inflated, the lateral inflorescences usually less exserted; rachis straight and
stiff, the hairs inconspicuous and shorter than the spikelets...2. A. furcatus.

Pedicellate spikelet reduced to 1 or 2 empty glumes; racemes in pairs from a broad,
conspicuous, usually inflated spathe; rachis flexuous, capillary, the hairs
conspicuous and as long as or longer than the spikelets.

Uppermost pair of racemes long-peduncled, their spathe inconspicuous, the
lateral pairs short-peduncled from large, inflated, aggregate, sometimes
blade-bearing sheaths...........-..2-0+ 2222-22-22 eee ee eee 3. A. elliottii.

Uppermost pair of racemes on peduncles not longer than those of the lateral ones,
all the spathes about equally inflated.

Spathes scattered or in small clusters along the slender culm; spikelets about
3mm. long......-------2e. ee eee eee eee erences 4. A. virginicus.
Spathes aggregate in a dense, flabellate or oblong, compound inflorescence;
spikelets about 4mm. long.....-..-----------+-+-+-+-+-- 5. A. glomeratus.

72 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

1. Andropogon scoparius Michx. LITTLE BLUESTEM.

Dry open hillsides and open woods; common. Eastern U. 8. (Schizachyrium
scoparium Nash.)

Like the other species of the genus an autumn grass. Sometimes called broom
sedge, but this name more properly belongs to A. virginicus, although the specific
name refers to a broom. The seeds of this and all our other species except A. furcatus
are dispersed by the wind, the rachis disarticulating, the woolly joints with spikelets
attached being easily blown about.

2. Andropogon furcatus Muhl. Bia BLUESTEM.

Open grassy ground and rocks along the Potomac; frequent. Eastern U. 8.

Taller than any other of our species of this genus. Often glaucous. A good forage
grass.

3. Andropogon elliottii Chapm.

Sterile open ground; frequent; especially abundant in the open land at College
Park and near Chevy Chase. Southeastern U. S., especially on the Coastal Plain,
north to Del.

Culms stiffer and not so tall as those of A. virginicus, the crowded inflated upper
sheaths bright pinkish or orange brown and persisting through the winter.

4. Andropogon virginicus L. BROOM SEDGE.

Dry sterile open ground, open woods, and old fields; common. Southeastern U. S.,
north to Mass.

Especially characteristic of acid soils in old fields. Turning bright rosy or orange
brown in November and standing until late February, forming, together with Andro-
pogon elliottii, a conspicuous feature of the winter landscape.

Andropogon ternarius Michx. (A. argenteus Ell.) is listed in Ward’s Flora. but
probably does not occur within our limits.

5. Andropogon glomeratus (Walt.) B. 8. P.

Open swamps; infrequent; Brightwood and eastward. Coastal Plain, from N. Eng.

southward. (A. macrourus Michx.)

5. SORGHASTRUM Nash.

1. Sorghastrum nutans (L.) Nash. INDIAN GRASS.
Common in open dry ground, old fields, and open woods. Aug.-Sept. Eastern
U.S. (Sorghum nutans A. Gray; Sorghastrum avenaceum Nash.)
The long panicles of golden brown spikelets with orange anthers are strikingly
handsome when in bloom, turning bronze at maturity.

6. HOLCUS L. Sorcuum.

To this genus belongs the cultivated H. sorghum L. (Sorghum vulgare Pers.; Andro-
pogon sorghum Brot.), the varieties of which are known as sorghum or sorgo, Kafir,
Milo, Durra, and others, found occasionally growing spontaneously where the seed has
been accidentally scattered.

1. Holcus halepensis J.. JOHNSON GRASS,

Commonly escaped from cultivation from Va. southward and westward throughout
the country; rare in waste ground in our region. Native of Eur. and Asia. (Sorghum
halepense Pers.)

7. SYNTHERISMA Walt.

Culms erect, branching at the base; rachis not winged........... 1. S. filiformis.
Culms decumbent, sometimes extensively creeping, branching throughout; rachis
wing-margined. _
Foliage glabrous; fruit brown; first glume wanting............... 2. S. ischaemum.
Foliage pilose; fruit pale gray; first glume minute.............. 3. S. sanguinalis.

FLORA OF THE DISTRICT OF COLUMBIA. 73

1. Syntherisma filiformis (L.) Nash.

Common in open ground throughout our region, especially to the east. Sept. South-
ern states, north to Mass. (Panicum filiforme L.; Digitaria filiformis Koeler.)

The only native species in our region.

2, Syntherisma ischaemum (Schreb.) Nash.

A weed in lawns, gardens, and waste ground, less troublesome than S. sanguinalis.
Aug.-Oct. Eastern U. 8. Native of Eur. (S. linearis Nash; Digitaria humifusa
Pers.)

3. Syntherisma sanguinalis (L.) Dulac. CRABGRASS.

A common and troublesome weed in lawns, and in cultivated and waste ground.
July till frost. Throughout the U.S.; native of Eur. (Panicum sanguinale L.; Digitaria
sanguinalis Scop.)

Plants in cultivated ground, with numerous branches rooting in all directions, sug-
gest a crab.

8. PASPALUM L.

Rachis broadly winged, partly infolding the spikelets; plants subaquatic.
1. P. dissectum.
Rachis not winged; plants terrestrial.
Spikelets 2.5 mm. long or more, borne singly in 2 rows.

Sheaths and blades pilose.........-------+------eeerre crete 2. P. longipilum.
Sheaths and blades glabrous or the sheaths ciliate only or the blades sparsely

pilose.
Blades elongate, reaching the base of the panicle or overtopping it; spikelets
suborbicular, 3-3.2 mm. long........---------+-+2e+e-57+ 3. P. circulare.
Blades shorter, the panicle much exceeding them; spikelets not over 2.8 mm.
long, broadly oval.........------++22222cer eer rce ert 4, P. laeve.

Spikelets not over 2 mm. long, borne in pairs, appearing as if in 3 or 4 rows.
Spikelets 1.6 mm. long or less; culms very slender.
Blades glabrous on both surfaces or pubescent above, linear-lanceolate.
5. P. longepedunculatum.
Blades densely pilose on both surfaces, linear.....------------- 6. P. setaceum.
Spikelets about 2 mm. long; culms less slender.
Sheaths and blades densely canescent or velvety; culms stiffly spreading.
7. P. psammophilum.
Sheaths ciliate only, the blades densely or sparsely pilose.
Blades linear, 3-5 mm. wide, commonly rather densely pilose.
8. P. pubescens.
Blades wider toward the middle, 6-10 mm. wide, usually sparsely pilose.
9, P. muhlenbergii.
1. Paspalum dissectum L.
Found on the Potomac Flats in 1900; not since found in our region. Autumn.
Atlantic Coastal Plain. (P. membranaceum Walt.)
2. Paspalum longipilum Nash.
Moist open ground; Takoma Park, Glen Sligo, and eastward. Aug.—Oct. Atlantic
Coastal Plain.
3. Paspalum circulare Nash.
Moist open ground and embankments, especially eastward. Aug. Conn. to N.C.
and Tex.
4. Paspalum laeve Michx.
Common in open ground and along roadsides. Aug.Sept. Southern states, north
to N. J.
The commoner form has blades pilose above, sometimes also toward the base beneath.
(P. australe Nash; P. laeve australe Hitchc.)

74 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

5. Paspalum longepedunculatum LeConte.

Open wooded slopes; Somerset and Fourmile Run, probably elsewhere. Sept.
Southern states, north to Md.
6. Paspalum setaceum Michx.

Gravelly or sandy clay soil; Takoma Park and Fourmile Run, probably elsewhere,
July-Sept. Southern states, north to N. J.
7. Paspalum psammophilum Nash.

Open sterile ground; found at Brookland in 1894. July. Atlantic Coastal Plain.
8. Paspalum pubescens Muhl.

Common in open woods and old fields. Aug.-Sept. Atlantic Coast to the Middle
West.
9. Paspalum muhlenbergii Nash.

Found in the same habitat and range as the preceding species, rather commoner
in our region,

Doubtfully distinct, even varietally.

9. PANICUM L.
Plants annual. Panicles open.
Spikelets warty. Plants glabrous............................. 13. P. verrucosum.
Spikelets smooth.
Sheaths glabrous; first glume only one-fourth as long as the spikelet, truncate.
1. P. dichotomifilorum.
Sheaths hirsute; first glume as much as half the length of the spikelet, pointed.
(CAPILLARIA. )
Panicles drooping; spikelets 4.5-5 mm. long..................6. P. miliaceum,
Panicles erect; spikelets not over 3.5 mm. long.
Spikelets 3-3.5 mm. long, acuminate; panicles narrow, usually less than half
as broad as long, or sometimes spreading at maturity....... 2. P. flexile.
Spikelets about 2 mm. long, acutish but not acuminate; panicles as broad as
long.
Panicles more than half the length of the entire plant; culms rather stout,
erect or ascending....... 22.2.0. 0 002 e cece e eee eee. 5. P. capillare.
Panicles not more than one-third the length of the entire plant; culms
erect or decumbent-spreading.
Culms stout, soon decumbent-spreading; blades about 1 cm. wide.
3. P. gattingeri.
Culms slender, erect, zigzag below; blades not over 6 mm. wide.
4. P. philadelphicum.
Plants perennial.
Spikelets short-pediceled, on short branchlets along the main branches of the
panicle, pointed. Sheaths keeled. (AGROSTOIDEA.)
Rootstocks present; culms but little compressed .......2......2222. 12. P. anceps.
Rootstocks wanting; culms strongly compressed, with keeled sheaths.
Ligule ciliate, 2-3 mm. long; panicle much exceeding the upper leaves.
11. P. longifolium.
Ligule erose or lacerate but not ciliate ; panicle not much longer than the upper
leaves.
Fruit stipitate; spikelets conspicuously secund; panicle usually purple,
10. P. stipitatum.
Fruit not stipitate; spikelets not conspicuously secund; panicle green or
slightly tinged with purple.
Spikelets 1.8-2 mm. long; panicle branches ascending or spreading.
8. P. agrostoides.
Spikelets about 2.5 mm. long; panicle branches erect or nearly so.
9. P. condensum.

FLORA OF THE DISTRICT OF COLUMBIA. 75

Spikelets long-pediceled, in an open panicle.
Rootstocks present; culms stout and erect; no winter rosette of leaves formed.
Spikelets 44.5 mm. long (rarely 3.5-5 mm.), beaked; first glume two-thirds
the length of the spikelet or more.....---.+++-+-++++++-777° 7. P. virgatum.
Spikelets not over 3.2 mm. long, not beaked; first glume about half the length
of the spikelet..........---------eerceerrerrets Ya, P. virgatum cubense.
Rootstocks wanting; plants usually forming a winter rosette of basal leaves.
Vernal phase blooming in the early summer, the culms simple, with open
terminal panicles; the autumnal phase much branched, the panicles reduced
and more or less included in the sheaths. (Subgenus DICHANTHELIUM.)
Blades elongate, not over 5 mm. wide, 20 times as long as wide. (DEPAU-
PERATA.) (See P. bicknellit and P. aculeatum.)
Spikelets about 3.5 mm. long, beaked.......------+++-- 14, P. depauperatum.
Spikelets 2-2.7 mm. long, not beaked.

Sheaths pilose.......-------+-2--- 20 ert ereecse rrr 15. P. linearifolium.

16. P. werneri.

Sheaths glabrous.......-----++----eereccrseserttres
Blades not elongate, usually not more than 10 times as long as wide.
Spikelets glabrous.
Spikelets about 1.5 mm. long. Nodes bearded; autumnal phase much
branched, reclining. ......--------+-+-++++0-7+> ..19. P. microcarpon.
Spikelets 2 mm. long or more.
Culms soon prostrate, the autumnal phase vinelike......26. P. lucidum.

Culms erect, the autumnal phase sometimes reclining but not vinelike.
Spikelets about 2.5 mm. long, pointed beyond the fruit.
25. P. yadkinense.
Spikelets 2 mm. long, not pointed beyond the fruit.
Nodes glabrous; autumnal phase erect, branched like a little tree.
23. P. dichotomum.

Nodes, at least the lowest, bearded; autumnal phase top-heavy,

reclining........-------22e2-eee seer etre 24. P. barbulatum.

Spikelets pubescent (sparsely so in P. scribnerianum).
Spikelets 3 mm. long or more.
Ligule 3-4 mm. long; blades velvety beneath, firm..... 43, P. ravenelii.
Ligule obsolete; blades not velvety beneath (except in P. boscit molle).
Nodes bearded; spikelets 44.5 mm. long.
Blades glabrous or nearly so on both surfaces....------ 50. P. boscii.
Blades velvety beneath.......-------+++++-++- 50a. P. boscii molle.
Nodes not bearded; spikelets mostly less than 4 mm. long.
Blades 1.5-4 cm. wide, cordate-clasping.
Sheaths glabrous; blades minutely ciliate at base.
49. P. latifolium.
Sheaths, at least the lower, tuberculate-hispid; blades not ciliate
at base....-.... wee c ewe cece cece ee eeeeees 48. P. clandestinum.
Blades rarely over 1 cm. wide, not cordate-clasping.
Pubescence ascending; spikelets 3.5-4 mm. long.
. 42. P. oligosanthes.
Pubescence spreading; spikelets 3.2-3.3 mm, long
Spikelets obtuse, 3.2-3.3 mm, long....-- 41. P. scribnerianum.
Spikelets acute, 8 mm. long...--.+--------- 45. P. aculeatum.
Spikelets less than 3 mm. long (see P. clandestinum).
Sheaths retrorsely pilose; plants light green, forming soft mats.
17. P. xalapense.
Sheaths not retrorsely pilose; plants erect, spreading or finally prostrate
but not forming soft mats.......--------+++eeeeec cert A, AA:

76 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

A. Ligule manifest, 2-5 mm. long (1-1.5 mm, long in P. tsugetorum).
Sheaths glabrous or the lowest sometimes pubescent.
Panicle narrow, one-fourth to one-third as wide as long.......... 27. P. spretum.
Panicle open, nearly as wide as long... -.. eee 28. P. lindheimeri.
Sheaths pubescent.
Spikelets 2.2-2.4 mm. long.
Pubescence on culms horizontally spreading; autumnal phase freely branching.
; 33. P. villosissimum.
Pubescence on culms appressed or ascending; autumnal phase rather sparingly
branching............00..02..0...2..2.......... 34. P. pseudopubescens.

Vernal blades glabrous or nearly so on the upper surface.
Ligule 1-1.5 mm. long; culm crisp-puberulent............ 36. P. tsugetorum.
Ligule 4-5 mm. long; culm papillose-pilose or becoming glabrous.
32. P. tennesseense,
Vernal blades pubescent on the upper surface.
Spikelets 1.3-1.5 mm. long; vernal blades long-pilose on the upper surface.
Autumnal phase widely decumbent-spreading, forming a mat, the vernal
culms soon geniculate-spreading; plants grayish olivaceous,
80. P. albemarlense.
Autumnal phase erect, not forming a mat; plants yellowish green.
29. P. meridionale.
Spikelets 1.6-1.8 mm. long; vernal blades appressed-pubescent.

Blades stiff, erect........0. 0000 00000..00000202-00 31. P. huachucae.
Blades lax, spreading....................... 3la. P. huachucae silvicola.
AA. Ligule obsolete or less than 1 mm. long. ,
Nodes bearded.
Blades velvety... 2.20.00... e eee. eee. 20. P. annulum.
Blades glabrous, or only the lower pubescent.
Sheaths and upper nodes glabrous............................... 22. P. clutei.

21. P. mattamuskeetense.
Nodes not bearded,
Plants densely gray-velvety throughout, a viscid glabrous ring below the nodes.
44. P. scoparium.
Plants not gray-velvety.
Sheaths, or some of them, pilose or hispid.

Pubescence papillose-hispid.......................... 48. P. clandestinum.
Pubescence ascending-pilose,
Spikelets 2mm. long................................... 35. P. addisonii.
Spikelets 1.3mm. long.................... 37a. P. columbianum thinium.

Sheaths glabrous or only puberulent.
Spikelets spheric, not over 1.8 mm. long. Blades with a thin white carti-
laginous margin.
Culms spreading; panicle as broad as long........... 38. P. sphaerocarpon.
Culms erect; panicle two-thirds as broad as long ........ 39. P. polyanthes.

Spikelets 2.5 mm. long.
Upper blades elongate, narrowed toward the base.....18. P. bicknellii.
Upper blades not elongate, cordate at base.
Culms crisp-puberulent; blades usually less than 1 cm. wide.
46. P. ashei.
Culms glabrous; blades usually 1.5 em. wide or more.
47. P. commutatum.

FLORA OF THE DISTRICT OF COLUMBIA. 77

Spikelets less than 2 mm. long.
Culms crisp-puberulent................-.---+-5-- 37. P. columbianum.
Culms glabrous.
Nodes glabrous; culms delicate, sparingly branching.
40. P. ensifolium.
Nodes bearded; culms slender but not delicate, very freely branching.
19. P. microcarpon.
1. Panicum dichotomiflorum Michx.
Common in moist ground and embankments; a weed in cultivated soil. Aug.—Sept.
Eastern and middle states. (P. proliferum of Ward’s Flora.)
2. Panicum flexile (Gattinger) Scribn.
Moist sandy soil; infrequent in our region. Sept. Eastern and middle states.
3. Panicum gattingeri Nash.
Open and waste ground; frequent; a weed in cultivated soil. Sept. Eastern and
middle states.
4. Panicum philadelphicum Bernh.
Open sandy or argillaceous soil; common. Aug.-Sept. Eastern and middle states.
5. Panicum capillare L. WITCH GRASS.
Open ground, fields, and waste places; common. Sept. A weed in cultivated soil.
Atlantic Coast to the Rocky Mts.
6. Panicum miliaceum L. HoG MILLET. BROOMCORN MILLET.
A weed in waste ground; rare. July-Aug. Escaped from cultivation in the north-
eastern and middle states; native of Eur.
7. Panicum virgatum L.
Open moist ground and open woods; frequent, especially near the Potomac. July-
Aug. Atlantic Coast to the Rocky Mts.
Ya. Panicum virgatum cubense Griseb.
Boggy pine woods; infrequent; College Park and Beltsville. July-Aug. Atlantic
Coastal Plain.
8. Panicum agrostoides Spreng.
Wet meadows and swales; infrequent. Aug. Eastern U. 8.
9. Panicum condensum Nash.
Swales near the Potomac below Washington; rare. Sept.—Oct. Atlantic Coastal
Plain.
10. Panicum stipitatum Nash.
Wet meadows and swales near the Eastern Branch and Potomac; frequent. Sept.
Eastern U. 8.
11. Panicum longifolium Torr.
Moist sandy or gravelly ground in the valley of the Eastern Branch; infrequent.
Aug. Atlantic and Gulf states.
12. Panicum anceps Michx.
Moist open ground or open woods; common. Aug. Eastern U.S.
13. Panicum verrucosum Muhl.
Wet sandy woods or shaded ditches; frequent from Takoma Park eastward. Aug.— .
Sept. Eastern and southern states and in northern Ind.
14. Panicum depauperatum Muhl.
Sterile woods; frequent. Eastern U.S.
15. Panicum linearifolium Scribn.
Dry woods along the north side of the Potomac; frequent. Eastern U.S.
16. Panicum werneri Scribn.
Pine woods; near Paint Creek. Me. to Mo. and Md.
17. Panicum xalapense H. B. K.
Rich alluvial woods or open ground along the Potomac from District Line to Great
Falls; frequent. Southern states, north to Md. (P. laxiflorum of Britt. & Brown,
Illustr. Fl.)

78 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

18. Panicum bicknellii Nash.

Rocky woods between Chevy Chase, Glen Echo, and Great Falls; near Paint
Creek, west of Beltsville; infrequent. Eastern U. 8.

Associated with Kalmia latifolia, Panicum ashei, and Antennaria.

19. Panicum microcarpon Muhl.

Swampy borders and swales or alluvial stream banks; common, especially eastward.
Eastern U.S. (P. barbulatum of Britton’s Manual.)

Forming great tangled masses with conspicuously bearded nodes and small divari-
cate blades on slender scorpioid branchlets.

20. Panicum annulum Ashe.

Rather rich rocky woods, between Chevy Chase, Cleveland Park, and Great Falls;
infrequent. Atlantic states, above the Coastal Plain, and in Mo. and Miss.
21. Panicum mattamuskeetense Ashe.

Magnolia bogs; Beltsville and east of Hyattsville; rare. Atlantic Coastal Plain,
Long Isl. to N. C.

22. Panicum clutei Nash.
Boggy swale, Kenilworth; rare. Atlantic Coastal Plain, Mass. to N. C.
Intergrades with P. mattamuskeetense; possibly only a form of that.

23. Panicum dichotomum L.
Dry and sterile woods; common. FEastern U.S.

24, Panicum barbulatum Michx.

Sterile and rocky woods; commoner than P. dichotomum. Eastern U. 8.
25. Panicum yadkinense Ashe.

Moist thickets and brushy places along streamlets; frequent. Southern Atlantic
states, north to Pa.

26. Panicum lucidum Ashe.

Magnolia bogs and boggy spots in pine woods; Takoma Park and eastward; found
in 1898 at Fort Myer. Southern states, north to N. Y.

Forming large clumps, the vinelike culms with spreading glossy blades prostrate
among sphagnum and underbrush.

27. Panicum spretum Schult.

Wet sandy open ground; College Park; rare. Atlantic Coastal Plain, Me. to ‘Tex.
28. Panicum lindheimeri Nash.

Wet sandy meadows or low open woods; common. Atlantic Coast to the Great
Plains.

29. Panicum meridionale Ashe.

Sandy or rocky woods and copses; frequent. R. I. to Ala.
30. Panicum albemarlense Ashe.

Low sandy wood borders and clearings; frequent southeastward below the fall line.
Eastern U. 8S.

31. Panicum huachucae Ashe.

Open grassy ground; infrequent. Mississippi Valley and northeastward.
3la. Panicum huachucae silvicola Hitchc. & Chase.

Open woods and clearings; common. Eastern U. 8.

32. Panicum tennesseense Ashe.

Wood borders and roadsides, usually in rather moist ground; common, especially
in the vicinity of the Potomac above Washington. Atlantic Coast to the Rocky Mts.
33. Panicum villosissimum Nash.

Dry or sandy open woods and clearings; common. Eastern U. 8.

34. Panicum pseudopubescens Nash.

Dry sandy open woods; found at Kenilworth in 1899. Southern Atlantic states to

Conn. (P. ovale of Gray’s Manual.)

FLORA OF THE DISTRICT OF COLUMBIA. 79

35. Panicum addisonii Nash.

Dry sandy pine woods near the junction of Bladensburg Road and Carters Lane,
east of Hyattsville. Coastal Plain, Mass. to 8. C.

A characteristic species of the sand-barrens of the Atlantic Coast; in our region
associated with sand-barren species,
36. Panicum tsugetorum Nash.

Sandy woods; below the fall line; infrequent. Northeastern U. 8., south to Va.
37. Panicum columbianum Scribn.

Rocky and sandy woods, especially eastward; frequent. Northeastern U. S.,
south to Va. ,
37a, Panicum columbianum thinium Hitchc. & Chase.

Dry sands of the flood plain in a loop of the Eastern Branch, east of Hyattsville.
Mass. to Va.

A characteristic plant of the sand barrens of the Atlantic Coast.
38. Panicum sphaerocarpon Ell.

Open ground everywhere, especially in sandy soil. Eastern U. 8.
39. Panicum polyanthes Schult.

Moist ground, wood borders, and clearings; frequent, especially below the fall line.
Southern Atlantic states to N. J.
40. Panicum ensifolium Baldw.

Open spot in white sand magnolia bog, Powdermill Swamp. Atlantic Coastal Plain,
north to N. J.
41, Panicum scribnerianum Nash.

Sandy open ground; frequent. Me. to Md. and westward. (P. pauciflorum of
Ward’s Flora.)
42. Panicum oligosanthes Schult.

Sandy, usually moist, open woods; below the fall line; infrequent. Southern
states, north to N. J.
43. Panicum ravenelii Scribn. & Merr.

Sandy or rocky open woods; frequent. Southern states, north to Md.
44. Panicum scoparium Lam.

Wet open ground, wood borders, and along streams; below the fall line; common.
Southern states, north to Mass. (P. viscidwm Ell.)
45. Panicum aculeatum Hitchc. & Chase.

Boggy wood borders and thickets; Takoma Park (type locality), Brightwood, and
east of Hyattsville. Coastal Plain from Long Isl. to N. C.

A rare species.
46. Panicum ashei Pearson.

Sterile or rocky oak and pine woods; common, Eastern U.S.

A characteristic plant of laurel and blueberry hillsides.
47. Panicum commutatum Schult.

In less sterile woods than those occupied by P. ashei, the two occasionally growing
together; common. Eastern U.S.
48. Panicum clandestinum L.

Moist open ground and wood borders and along streamlets; common. Eastern U. 8.

The ripe grains remaining in the crowded sheaths well into the winter afford food
for birds.
49, Panicum latifolium L.

Rich rocky woods along the Potomac above Washington; frequent. Eastern U. S.
(P. macrocarpon LeConte.)
50. Panicum boscii Poir.

Wooded slopes everywhere; common, Eastern U.8. (P. porterianum Nash.)
50a. Panicum boscii molle (Vasey) Hitchc. & Chase.

Same habitat as the species;commoner. Eastern U.S. (P. latifoliwm molle Vasey.)

80 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

10. ECHINOCHLOA Beauv.

Sheaths glabrous; awns rarely over 3 cm. long; panicle rarely over 20 cm. long, not

drooping.........2..22-2 22. eee eee eee eee eeee 1. E. crusgalli
Sheaths hirsute; awns 3-5 cm. long; panicle drooping, commonly 30-40 em. long.

2. E. walteri.

1. Echinochloa crusgalli (L.) Beauv. BARNYARD GRASS. COCKSPUR.

Moist low open ground; common; an introduced weed. Aug.—Sept. Throughout
the U.8., except in the northern tier of states; nativeof Eur. (Panicum crusgalli L.)
2. Echinochloa walteri (Pursh) Nash.

In swales; Potomac flats and southward; infrequent. Aug.—Sept. Atlantic
Coastal Plain, and about the head of Lake Michigan. (Panicum walteri Pursh; P.
crusgalli hispidum A. Gray.)

11. CHAETOCHLOA Scribn.

Plants perennial by short knotty rootstocks...................-.--- 1. C, geniculata.
Plants annual.
Bristles downwardly barbed .................----.--2-.-.---------- 3, C. verticillata.
Bristles upwardly barbed.
Bristles 5 or more in each cluster; spikes yellowish.............2. C. lutescens.

Bristles 1-3 in each cluster; spikes green or purplish.
Spikelet articulate below the glumes, the complete spikelet shelling out,

leaving a cuplike receptacle...................0.-.--------- 4. C. viridis.
Spikelet articulate above the glumes, only the fruit shelling out, leaving the
persistent glumes and sterile lemma.................--..----- 5. C. italica.

1. Chaetochloa geniculata (Lam.) Millsp. & Chase.

Moist meadows and along ditches; frequent. Sept. Eastern U. 8. (Setaria
imberbis Roem, & Schult.; C,. imberbis Scribn.)

2. Chaetochloa lutescens (Weigel) Stuntz. YELLOW FOXTAIL.

Open waste and cultivated ground everywhere. July-Sept. Common east of the
Rocky Mts., rare on the Pacific Coast; introduced from Eur.

A troublesome weed in lawns and gardens. In mowed lawns the culms become
prostrate and fruit when 10-20 cm. long. (Setaria glauca and Chaetochloa glauca of
authors. )

8. Chaetochloa verticillata (L.) Scribn.

Open waste ground; uncommon. July-Aug. Eastern and middle states. Intro-
duced from Eur. (Setaria verticillata Beauv.)

4, Chaetochloa viridis (L.) Scribn. GREEN FOXTAIL.

Open waste ground and river flats; frequent. June~Aug. Throughout the U.S.;
introduced from Eur. (Setaria viridis Beauv.)

Not an aggressive weed in this region.

5. Chaetochloa italica (L.) Scribn. MILLET.

Dumping grounds and along railroads. July. Throughout the U.S., except in the
mountains, as an escape from cultivation; native of Eur. (Setaria italica Roem. &
Schult.)

Plants growing spontaneously vary in size from 30 cm. or less to 1.5 meters tall.

12, CENCHRUS L.

1. Cenchrus pauciflorus Benth. SANDBUR.

Sandy ground, along railroads and trolley tracks to the eastward; common in the
vicinity of Bennings. July-Sept. Throughout the U.S. (C. tribuloides of Ward’s
Flora; C. carolinianus of recent manuals, not Walt.)

FLORA OF THE DISTRICT OF COLUMBIA. 81

18. ZIZANIA L. :

1, Zizania palustris L. WILD RICE.

In shallow water, covering extensive areas in the marshes along the Eastern Branch,
bordering Analostan Island, and elsewhere along the Potomac; rarely growing in
pockets of wet soil among rocks on islands. July-Sept. Eastern and middle states.
(Z. aquatica of Ward’s Flora.)

The plants are annuals, though the large size and pure stands give the impression of
a perennial. Also called Indian rice and water rice. Plate 13 shows this as it grows
in Eastern Branch in summer.

14, HOMALOCENCHRUS Mieg.

Spikelets 2.5-3 mm. long; branches single, nearly straight, spikelet-bearing toward

the end............. 0. ee ee ce eee nee e eee eee 1. H. virginicus.
Spikelets 4-5 mm. long; lower branches clustered, spikelet-bearing from below the
middle........... 2.0.00 eee eee eee eee eee eee e eee eee 2. H. oryzoides.

1. Homalocenchrus virginicus (Willd.) Britton. WHITE GRASS.
Swampy woods and copses. Aug.—Sept. Eastern U.S. (Leersia virginica Willd.)
2. Homalocenchrus oryzoides (L.) Poll. RICE CUT-GRASS.

Wet open ground, along streams, and in railroad ditches; common. Sept. Through-
out the U. S.; alsoin Eur. and Asia. (Leersia oryzoides L.)

15. PHALARIS L.

Plants annual; heads ovate; glumes wing-keeled...........-.----- 1. P. canariensis.
Plants perennial; panicle 6-15 cm. long, open during anthesis; glumes not wing-

keeled...........--------.2------- Lecce eee eect eee ee eens 2. P. arundinacea.
1. Phalaris canariensis L. CANARY GRASS.

Waste ground; an infrequent escape from cultivation. May-June. Atlantic and
Pacific Coast states; introduced from Eur.
2. Phalaris arundinacea L. . REED CANARY GRASS.

Wet ground or in shallow water; frequent. June. Northern states, south to Md;
also in Eur. and Asia.

In past years popular as an ornamental, especially the form called ribbon grass,
with blades striped with white (var. picta L.).

16. ANTHOXANTHUM L.

1. Anthoxanthum odoratum L. SWEET VERNAL GRASS.
Meadows, lawns, old fields, and open woods; common everywhere. May. Atlantic
and Pacific Coast states; naturalized from Eur.

17. ARISTIDA L. NEEDLE GRASS.

Plants perennial, 30-60 cm. tall; spikelets crowded on the short erect branches of a

marrow panicle. ..........-.. ee eee eee eee eee ee eee eee eee 1. A. purpurascens.
Plants annual; spikelets not crowded, the panicle nearly simple.
Middle awn coiled at base at maturity.............-..----------- 2. A. dichotoma.

Middle awn not coiled.
Lateral awns 2-6 mm. long, much shorter than the middle one.....3. A. gracilis.
Lateral awns 3.5-7 cm. long, about as long as the middle one..... 4. A. oligantha.

1. Aristida purpurascens Poir.
Sterile woods and rocky banks of rivers; frequent. Eastern U. 8.
All the species of Aristida flower in late summer and autumn.

69289—19——6

82 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

2. Aristida dichotoma Michx. POVERTY GRASS.
Sterile open ground; frequent. Eastern U.S.

3. Aristida gracilis Ell.
Sterile open ground; infrequent. Eastern U. 8.

4. Aristida oligantha Michx.
Fields and open ground; frequent. Southern states, north to N. J.

18. STIPA L. Sprar Grass.
1. Stipa avenacea L.

Dry or moist woods; frequent. May-June. Eastern U.S.
Ripe fruit brown, the sharp point brown-bearded.

19. MUHLENBERGIA Schreb.

Panicle diffuse, the pedicels capillary........................-... 1. M. capillaris.
Panicle contracted, usually narrow.
Culms delicate, decumbent at base, without rootstocks; glumes not over one-fourth
as long as the lemma.
First glume obsolete; second glume minute.................... 2. M. schreberi.
First glume about one-fifth, the second about one-fourth as long as the lemma.
2a. M. schreberi palustris.
Culms erect, from scaly rootstocks; glumes at least half as long as the lemma.
Blades ascending or erect; glumes narrow, acuminate, about as long as the body
of the lemma.
Culms smooth below the nodes; lemma acuminate........... 3. M. mexicana.

Culms pubescent below the nodes; lemma usually long-awned.
4. M. umbrosa.

Blades divaricate; glumes broadly ovate, one-half to three-fourths as long as the

floret.
Lemmas awned.... 2.2.22... 22 e eee cece cece ce ccc cceccee 5. M. tenuiflora.
Lemmas awnless...... 2... 22.2 cece cece cece ccc ceececcccce 6. M. sobolifera.
1. Muhblenbergia capillaris (Lam.) Trin. Harr GRAss.

Rocky woods; infrequent. Eastern U. S.

All our species of Muhlenbergia are late-flowering.
2. Muhlenbergia schreberi J. F. Gmel.

Open ground; common, Aug—Sept. Eastern U.S. (M. diffusa Willd.)

This and the following species are sometimes called nimble Will and wire grass,
because of the slender tough culms,
2a. Muhlenbergia schreberi palustris Scribn.

Open moist grassland ; vicinity of Brightwood, the type locality. Also in III.
8. Muhlenbergia mexicana (L.) Trin.

Moist low woods and open ground; common. Northern states, south to N. C.

The scaly rootstocks of this and the following three species are conspicuous.
4. Muhlenbergia umbrosa Scribn.

Moist open ground and thickets; infrequent. Northern states, south to N.C. (M.
sylvatica Torr.)
5. Muhlenbergia tenuiflora (Willd.) B.S. P.

Moist rocky soil and moist woods; infrequent. EasternU.S. (M. willdenovii Trin.)
6. Muhlenbergia sobolifera (Muhl.) Trin.

Rocky woods; infrequent. Northern states, south to Va.

20. BRACHYELYTRUM Beauv.

1, Brachyelytrum erectum (Beauv.) Schreb.
Rocky or moist woods; infrequent. July-Aug. Northern states, south to Ga. (B.
aristatum Beauv. )

FLORA OF THE DISTRICT OF COLUMBIA. 83

21. PHLEUM L.
1. Phleum pratense L. TIMOTHY,
Meadows, pastures, and open ground. June-July. Cultivated as a meadow grass
and naturalized throughout the cooler and moist parts of the U. §.; native of Eur.

22. ALOPECURUS L.

Spike cylindric; glumes distinctly ciliate on the keels............ 1. A. geniculatus.
Spike tapering above and below; glumes scarcely ciliate on the keels. .2. A. agrestis.

1. Alopecurus geniculatus L.

Banks of ditches and streams; rare. May-June. Widely distributed in the U. $.;
also in Eur, and Asia, (Including A. geniculatus aristulatus of Ward’s Flora.)
2. Alopecurus agrestis L.

Old fields and waste places; rare. A European grass, occasionally found introduced
in waste places.

23. SPOROBOLUS R. Br. Drop-SHED GRASS.

Plants perennial; palea acuminate, longer than the lemma........ 1. S. clandestinus.
Plants annual; palea not longer than the lemma.
Spikelets 4 mm. long; lemma pubescent...........-...---- 2. S. vaginaeflorus.
Spikelets 2.5-3 mm. long; lemma glabrous.............---------- 3. S. neglectus.

1. Sporobolus clandestinus (Spreng.) Hitche.
Sandy soil; Great Falls to High Island; infrequent. Eastern U.S. (Vilfa aspera
of Ward’s Flora.)
All our species of Sporobolus are fall-flowering.
2. Sporobolus vaginaeflorus (Torr.) Wood.
Waste ground or sandy soil; frequent. Eastern U.§
3. Sporobolus neglectus Nash.
Waste ground or sandy soil; frequent. Northern states, south to Va.

24. CINNA L.
1. Cinna arundinacea L. WooD REED-GRASS.
Moist woods; frequent. Aug—Sept. Northern states, south to N. C.

25. AGROSTIS L. BENT GRass.

Palea present. Panicle many-flowered, rather compact; plants usually tall.
Ligule of the culm leaves long, mostly 3-5 mm.; panicle large and many-flow ered,

usually closing. after flowering; culms 50-100 em. tall.......... 1. A. palustris.
Ligulé short; panicle small, rather few-flowered, open and spreading, remaining
open after flowering; culms usually less than 40 cm. tall....... 2. A. capillaris.

Palea wanting.
Panicle diffuse, the branches long and capillary, branching toward the end.
3. A. hiemalis.
Panicle spreading but not diffuse, the branches branching below the middle.
_*. A. perennans.
1. Agrostis palustris Huds. REDTOP.
Meadows, pastures, and open ground. June-July. Cultivated throughout the
northern states as a meadow and pasture grass, and commonly escaped into open
moist ground; native of Eur. (A. alba of Ward’s Flora.)
2. Agrostis capillaris L. RaHovE ISLAND BENT.
Open grassland; frequent. Cultivated as a lawn grass and escaped in the north-
eastern states: native of Eur. (A. alba vulgaris Thurb.; A. vulgaris With.)

84 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

3. Agrostis hiemalis (Walt.) B.S. P.

Open, dry or moist ground. June-July. Common throughout the U. 8. (A.
scabra Willd.)

A low delicate grass, the mature, very diffuse panicle breaking away and rolling
before the wind as a tumbleweed. Sometimes called tickle-grass.
4. Agrostis perennans (Walt.) Tuckerm. °

Dry or moist woods; common. Aug.-Sept. Northern states, south to N. C.
- The ordinary form is erect and rather stiff. A form found in moist shady places
has decumbent stems and delicate, divaricately branched panicles.

26. CALAMAGROSTIS Adans. REED-GRASS.

Spikelets 3-3.5 mm. long; rudiment hairy throughout; panicle rather open.
1. C. canadensis.
Spikelets 6-7 mm. long; rudiment hairy at the tip; panicle contracted.

2. C. cinnoides.
1. Calamagrostis canadensis (Michx.) Beauv.

Swales and moist woods; rare; Bladensburg; southwest of Rockville, near Cabin
John road. June-July. Northern U.S., south to Md., and in the mountains to N.C.
2. Calamagrostis cinnoides (Muhl.) Barton.

Boggy woods, especially magnolia bogs below the fall line. Aug. Northern states,
south to Ga. (C. nuttalliana Steud.)

27. NOTHOLCUS Nash.

1. Notholcus lanatus (L.) Nash. VELVET GRASS.
Meadows and waste places; infrequent. June. Naturalized from Eur. in the
eastern states and on the Pacific Slope. (/olcus lanatus 1.)

28. AIRA J..
1. Aira caryophyllea L.
Dry open ground; infrequent. May. Northern states and Pacific Slope; natu-
ralized from Eur,

29. DESCHAMPSIA Beauv.

1. Deschampsia flexuosa (L.) Trin.
Dry woods; infrequent. May-June. Northern states, south to N. C.; also in
Eur. (Aira flexuosa 1.)
30. TRISETUM Pers.

1. Trisetum pennsylvanicum (I..) B.S. P.
Bogs; rare. Eastern U.S. (7. palustre Torr.)

31. SPHENOPHOLIS Scribn.

Panicle narrow, densely flowered; glumes equal in length, about 2 mm. long, the
second much broadened above, 1 mm. wide.................... 1. S. obtusata.
Panicle lax, the branches more or less spreading; glumes unequal in length, the
second longer, widened above, 0.5-0.75 mm. wide.
Glumes subequal, the second broadly obovate, obtuse; florets obtuse, the second

SCADrOUS.... 2... Lecce eee cece ec eceeeees 2. S. nitida.
Glumes unequal, the first shorter than the narrowly obovate second one; florets
mostly acute, glabrous.........2.2. 20000022 eee eee eee eee ee 3. S. pallens.

1. Sphenopholis obtusata (Michx.) Scribn.
Rocky woods; rare; Great Falls, on the Virginia side; also collected by Ward and
by Seaman, the localities not recorded. June. Conn. to Fla. and westward.

FLORA OF THE DISTRICT OF COLUMBIA. 85

2. Sphenopholis nitida (Spreng.) Scribn.

Shaded hillsides; infrequent. May. Northeastern states, south to Ga.
3. Sphenopholis pallens (Spreng.) Scribn.

Rocky woods; frequent. May-June. Northern states, south to N. C. (Eatonia
pennsylvanica A. Gray.)

32. AVENA L.

1. Avena sativa L. Oats.

Cultivated as a cereal and escaped, especially where the grain is fed or handled.
Native of Eur. and Asia.

33. ARRHENATHERUM Beauv.

1. Arrhenatherum elatius (L.) Beauv. TALL OAT GRASS.

Meadows and waste places; infrequent. June-July. Cultivated as a meadow grass
and naturalized in waste places and grassland in the northern states and southward
to Tenn.; native of Eur.

34. DANTHONIA DC.

Teeth of lemma acute or acuminate...............2...-0.------ eee eee 1. D. spicata.
Teeth of lemma bearing awns as long as the spiral section of the central awn.

2. D. compressa.
1. Danthonia spicata (L.) DC.

Dry open woods and sterile hills; common. June. Northern states, south to N. C.
The species of Danthonia produce cleistogamous spikelets at the base of the lower
sheaths of the culm.
2. Danthonia compressa Austin.
Dry woods; infrequent; Great Falls; Takoma Park. June. Me. to N. C.
Plant usually taller and panicle more open than in the preceding.

35. CAPRIOLA Adans.

1. Capriola dactylon (L.) Kuntze. BERMUDA GRASS.

Pastures and open dry ground; common, Summer. Cultivated as a pasture grass
in the southern states and thoroughly naturalized as far north as Long Isl.; native of
Eur, (Cynodon dactylon L.)

36. SPARTINA Schreb.
1. Spartina michauxiana Hitchc. CoRD-GRASS.
Marshes and river banks; infrequent. Aug. Northern states, south to Va. (S.
cynosuroides of Ward's Flora.)

37. GYMNOPOGON Beauv.

1. Gymnopogon ambiguus (Michx.) B.S. P.
Sandy open woods; infrequent; east of the fall line. July-Sept. Southern states,
north toN. J. (G. racemosus Beauv.)

38. ELEUSINE Gaertn.

1. Eleusine indica (L.) Gaertn. GOOSE GRASS.
A weed in open dry ground, especially in yards and along paths; common. Aug.-
Sept. Eastern U. S.; naturalized from the Old World.

39. LEPTOCHLOA Beauv.

1. Leptochloa fascicularis (Lam.) A. Gray.
Wet soil; rare; Alexandria (Steele). Southern states, north to Mass. (Diplachne.
fascicularis Beauv.)

86 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

40. PHRAGMITES Trin.

1. Phragmites communis Trin. REED.
Marshes; Eastern Branch below the steel plant. Aug.-Sept. Cosmopolitan. (2.
phragmites Karst.)
41. TRIDENS Roem. & Schult.

1. Tridens flavus (L.) Hitche. PURPLE TOP.
Open woods and dry open grounds; common. Aug.—Sept. Eastern U.S. (Tricuspis
seslerioides Torr.)
The upper part of the culm and the branches of the panicle become sticky at matu-
rity and retain dust and small particles,

42, ERAGROSTIS Beauv.

Plants perennial; panicle diffuse, usually purple.............-.-- 1. E. pectinacea.
Plants annual; panicle open or contracted but not diffuse (except in F. capillaris).
Culms creeping; plants dioecious or polygamous........-...----- 2, E. hypnoides.

Culms erect or spreading, not creeping; flowers perfect.
Spikelets 2-5-flowered.,

Plants erect, branched from the base; panicle diffuse, open, pale or green;

pedicels mostly over 5mm, long................-----.--- 3. E. capillaris.

Plants decumbent or spreading, branched above the base; panicle oblong, the

branchlets rather crowded, usually purple; pedicels usually less than 5 mm.

long... 2.2 ee eee eee cece ceececeecececeeee 4, E. frankii.

Spikelets 5-many-flowered.

Lemmas glandular on the keel; spikelets about 3 mm. wide; panicle somewhat

contracted... 2.2.2... .2 ee eee eee eee ween cece ee eee 5. E. cilianensis.

Lemmas not glandular on the keel; spikelets less than 3 mm. wide; panicle more
open,

Spikelets about | mm. wide; panicle branches pilose in the axils.
6. E. pilosa.
Spikelets 1.5-2 mm. wide; panicle branches usually not pilose in the axils.

Plant not glandular; spikelets about 1.5 mm, wide, the pedicels appressed

along the main branches of the open panicles. ..... 7. E. caroliniana.

Plant glandular on the margins of the blades and sometimes on other por-

tions; spikelets about 2 mm. wide, on spreading pedicels; panicle

rather compact......-......... ccc eee e ence cece eeeeeeeee 8. E. minor.

1, Eragrostis pectinacea (Michx.) Nees.

Sandy fields; frequent. Late summer. Eastern U.S.

At maturity the panicle breaks away as a tumbleweed.
2. Eragrostis hypnoides (Lam.) B.S. P.

Sandy banks of streams, especially parts exposed at low water; frequent along the
Potomac and other larger streams. Aug.—Sept. Eastern U.S. (E. reptans Nees.)
3. Eragrostis capillaris (L.) Nees.

Open woods; infrequent. Aug.-Sept. Eastern U.S.

The plant has a pleasant lemon scent.

4. Eragrostis frankii (Fisch. Mey. & Lall.) Steud.

Moist open soil; infrequent; Glen Echo; Cabin John, Eastern U. 8.

5. Eragrostis cilianensis (All.) Link. STINK GRASS.

A common weed in open ground and waste places. Common through the warmer
parts of the U. S.; naturalized from Eur. (2. major Host; &. megastachya Link; FE.
poaeoides megastachya A, Gray; I. poaeoides of Ward’s Flora.)

The plants when fresh exude a disagreeable odor, this probably originating in the
glands along the keels of the lemmas.

FLORA OF THE DISTRICT OF COLUMBIA. 87

6. Eragrostis pilosa (L.) Beauv.

Moist places; infrequent. Eastern states; introduced from Eur.
7. Eragrostis caroliniana (Spreng.) Scribn.

A common weed in open moist ground. Throughout the eastern and southern
U.S. (#. purshii Schrad.)
8. Eragrostis minor Host.

Open waste ground; rare; Beltsville; Anacostia. Late summer. Occasional at
scattered localities throughout the U. S.; introduced from Eur. (£. eragrostis Karst.)

43. MELICA L.

1. Melica mutica Walt.
Rocky woods; frequent above the fall line. Southern states, north to Pa.

44, UNIOLA L.

Panicle contracted, slender; spikelets 5-7 mm. long, narrow.............. 1. U. laxa.
Panicle open, the branches drooping; spikelets 1.5-3 cm. long, broad and very flat.

2. U. latifolia.
1. Uniola laxa (L.) B.S. P.

Moist woods; east of the fall line; infrequent. Summer. Southern states, north-
ward to Long Isl. (U. gracilis Michx.)
2. Uniola latifolia Michx.
Rich woods; above the fall line. Summer. Southern states, north to Pa.
A handsome grass, the drooping panicles of large, very flat spikelets being very
striking.
* 45. DACTYLIS L.

1. Dactylis glomerata L. ORCHARD GRASS.
Cultivated as a meadow grass; frequently established in grassland and along road-
sides. May. Native of Eur.

46. POA L. BLuecrass.
Plants annual.
Florets not cottony at base; intermediate nerves of lemma distinct....1. P. annua.
Florets with cottony hairs at base; intermediate nerves indistinct.2. P. chapmaniana.
Plants perennial.
Creepingjrootstocks present.
Culms distinctly flattened; plants not tufted; panicles contracted.
3. P. compressa,
Culms terete or obscurely flattened; plants tufted; panicles open.
Lower branches of the panicle usually in twos; basal leaves usually as long as

the culm......... eee eee eee eee eect eee neee 4. P. cuspidata.
Lower branches of the panicle usually in fives; basal leaves shorter than the
CUM 2. ce cece eee eee e eee eeeeeee 5. P. pratensis.

Creeping rootstocks wanting.
Lemma not cobwebby at base, conspicuously scarious at the rounded apex.
6. P. autumnalis.
Lemma cobwebby at base.
Sheaths upwardly scabrous; marginal nerves of the lemma glabrous.
7. P. trivialis.
Sheaths glabrous; marginal nerves of the lemma pubescent.
Intermediate nerves of the lemma faint; branches of the panicle ascending
or spreading; lemma usually purple-tinged ..............8. P. palustris.
Intermediate nerves of the lemma prominent; branches of the panicle finally
reflexed; lemma green...........2..00--2e-e-eeeeeeeee 9. P. sylvestris.

88 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

1. Poa annua L.

A common weed in lawns and waste places. Flowering in early spring or even in
warm weather during the winter. Common throughout the warmer parts of the
U.S., and in the Old World.

2, Poa chapmaniana Scribn.

Arlington Farm (Wheeler). Open ground, southern states.

8. Poa compressa L. CANADA BLUEGRASS.

Grassland and waste places, especially in sterile soil; a weed in gardens. June.
Introduced from Eur. and now distributed throughout the U. 8. (Including P. com-
pressa gracilis of Ward’s Flora.)

4. Poa cuspidata Nutt.

Rocky woods; infrequent; mostly above the fall line. Apr. N. Y. to Ga. and III.
(P. brachyphylla Schult.; P. brevifolia Muhl.)

Except the introduced P. annua this is the earliest of all our grasses to bloom.
5. Poa pratensis L. KENTUCKY BLUEGRASS.

Common in grassland. May. Cultivated as a lawn and pasture grass in the cooler
parts of the U. S. and well established; native of Eur.

6. Poa autumnalis Muhl.

Low woods; frequent. May. Southern states, north to Pa. (P. flerwosa Muhl.)
7. Poa trivialis L. ROUGH-STALKED MEADOW GRASS.

Moist places, ditches, and river banks; infrequent; along the Potomac above
Georgetown. June. Introduced from Eur.

8. Poa palustris L.

Moist meadows; rare. July. Southern states, north to Pa.; also in Eur. and Asia.

(P. triflora Gilib. )
9. Poa sylvestris A. Gray.
Rocky woods; frequent. May. Eastern U. S.

47. PANICULARIA Fabr.

Spikelets terete, 1.5-2 em. long...................0........ 1. P. septentrionalis.
Spikelets ovate or oblong, usually not over 7 mm. long.
Panicle contracted, oblong.............2....00. 0c cece ee eee ec eeeeee 2. P. obtusa.

Panicle open, lax.
Spikelets 3-4 mm. wide; lemmas obscurely nerved.
Lemmas about 2.5 mm, long; spikelets usually not over 5-flowered; middle
nodes of panicle with 3-5 primary branches; panicle 3-5 times branched.

3. P. laxa.

Lemmas a little over 3 mm. long; spikelets usually more than 5-flowered;
middle nodes of panicle with 1-3 primary branches; panicle 2-3 times
branched ............... 2220200200 e eee ec cee eee ee eee 4. P. canadensis.

Spikelets not over 2.5 mm. wide; lemmas prominently nerved.
Glumes short and rounded, the lower about | mm, long; lemmas about 2 mm.

long... eee eee e cece ee eees 5. P. nervata.
Glumes oblong, the lower 1.5-2 mm. long; lemmas about 3 mm. long.
6. P. pallida.

1, Panicularia septentrionalis (Hitchc.) Bicknell.

Marshes and river banks; infrequent; Bladensburg; Broadwater. June. North-
ern states, south to Va. (Glyceria septentrionalis Hitchc.; G. fluitans of Ward’s Flora.)
2, Panicularia obtusa (Muhl.) Kuntze.

Swales and river banks; rare; Oxon Run (Steele). Aug. Near the coast, N. Eng.
and southward. (Glyceria obtusa Trin.)

3. Panicularia laxa Scribn.

Swales; rare; Terra Cotta Swamp (Ward); Suitland. June. Me. toMd. (Glyceria

laxa Scribn.; G. aquatica of Ward’s Flora.)

FLORA OF THE DISTRICT OF COLUMBIA. 89

4. Panicularia canadensis (Michx.) Kuntze. RATTLESNAKE GRASS.
Swales below the fall line; infrequent. Summer. Northern states, south to Md.
(Glyceria canadensis Trin. )
5. Panicularia nervata (Willd.) Kuntze.
Swales and wet places; frequent. May-June. Throughout the U. 8. (Glyceria
nervata Trin.)
6. Panicularia pallida (Torr.) Kuntze.
Swales and stream borders; rare; Bladensburg (Steele). June. Northern states,
south to Va. (Glyceria pallida Trin.)

48. FESTUCA L. FrscueE GRAss.

Plants annual.
Glumes somewhat unequal, the lower 3 mm. long; spikelets 5-13-flowered; lemma
without scarious margin; awn usually not longer than the lemma.
1. F. octoflora.
Glumes very unequal, the lower 1.5-2 mm. long; spikelets 1-5-flowered; lemma
scarious-margined; awn about twice as long as the lemma......... 2. F. myuros.
Plants perennial.
Blades involute; panicle short and contracted.
Culms erect, pale at base.........-.-----+---+----- wee e eee e cece eee 3. F. ovina.
Culms decumbent and usually purplish at base........----.-------- 4. F. rubra.
Blades flat; panicle long and narrow, or open with spreading branches.
Lemmas 5-7 mm. long; panicle narrow, with short erect branches. .5. F. elatior.
Lemmas about 4 mm. long; panicle very loose, with long spreading or drooping
branches. ..........----- 2-0-2 eee eee ee ee eee ee eee ee eeee 6. F. obtusa.

1. Festuca octoflora Walt.
Open or sterile ground; common. May-June. Throughout the U.S. (F. tenella
Willd.)
2. Festuca myuros L.
Open ground; frequent. June. Eastern states; naturalized from Eur.
3. Festuca ovina L. SHEEP FESCUE.
Pastures and grassland; infrequent. June, Introduced from Eur.; occasionally
cultivated as a pasture grass.
4, Festuca rnbra L, RED FESCUE.
Sometimes cultivated in grass mixtures; occasionally escaped. June. Native of
Eur.
5. Festuca elatior L. MEADOW FESCUE.
Grassland and open ground; frequent. June. Cultivated as a meadow grass;
introduced from Eur.; well established in many places.
6. Festuca obtusa Spreng.
Rocky or rich woods; frequent above the fall line. May-June. Eastern states.
(F. nutans Willd.)
49, BROMUS L. BRoME GRASS.

Spikelets much flattened, the lemmas keeled, the awn not more than 2 mm. long.

1. B. unioloides.

Spikelets terete or slightly flattened, the lemmas not keeled or keeled only toward
the apex, the awn conspicuous (except in B. inermis).

Plants perennial.

Creeping rootstocks present; lemma glabrous, awnless or mucronate.
2. B. inermis.

Creeping rootstocks wanting; lemma pubescent, awned.
Sheaths usually not overlapping, rather loosely pilose.......-- 3. B. purgans.
Sheaths overlapping, densely soft-pilose...........--- 3a. B. purgans incanus.

90 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Plants annual.
Lemmas narrow, gradually acuminate.
Second glume usually less than 1 cm. long; pedicels capillary, flexuous.
4. B. tectorum.
Second glume more than 1 cm. long; pedicels not capillary and flexuous.

Awn about 2 cm. long; first glume about 8 mm. long.......... 5. B. sterilis.
Awn 3-5 cm. long; first glume about 15 mm. long............ 9. B. villosus.
Lemmas broad, abruptly narrowed above, glabrous.
Sheaths glabrous... 22.2.2. 0020 000000002 c eee eee eee 6. B. secalinus.
Sheaths pilose.
Panicle rather dense.............. 0. ..202.ceeeeeee eee ....8, B, racemosus.
Panicle open.
Lemma smooth, the awn straight...................... 7. B. commutatus,
Lemma scabrous, the awn divergent...................- 10. B. japonicus.
1, Bromus unioloides (Willd.) H. B. K. RESCUE GRASS.

Occasionally escaped from cultivation in the vicinity of Arlington Farm. Culti-
vated in the southern states as a forage grass. Originally from S. Amer.
2. Bromus inermis Leyss. AWNLESS BROME GRASS.
. Occasionally escaped from the experimental plots or propagating grounds. Culti-
vated in the northwestern states as a forage grass. Originally from Eur.
8. Bromus purgans L.

Rich or rocky woods; frequent. June-July. Eastern U.S. (B. ciliatus purgans
A. Gray; B. ciliatus of Ward’s Flora.)
3a. Bromus purgans incanus Shear.

Rocky woods along the Potomac; infrequent. Aug. Pa. to Va. and westward.
4. Bromus tectorum L.

A weed in waste ground; infrequent. June. Introduced from Eur.
5. Bromus sterilis L.

Waste places; rare; Old Observatory (Steele); Holmead (Ward); Uniontown (Ward).
June. Introduced from Eur.
6. Bromus secalinus L. CHESS.

Fields and waste ground; frequent. June. Introduced from Eur.

Also called cheat.
7. Bromus commutatus Schrad.

Waste places; frequent. June. Introduced from Eur.
8. Bromus racemosus L.

Waste places; infrequent. June. Introduced from Eur. (B. mollis of Ward’s
Flora.)
9. Bromus villosus Forsk.

Waste places; becoming frequent from College Park to Beltsville. June. Intro-
duced from Eur.
10. Bromus japonicus Thunb.

Waste places; near Suitland. July. Introduced from Eur.

50. LOLIUM L. Rye arass.

1. Lolium perenne L. PERENNIAL RYE GRASS,
Grassland and open ground; common. June. Cultivated asa lawn grass, especially
in parks; criginally from Eur,

51. AGROPYRON Beauv. WuHEatT arass.

1. Agropyron repens (I..) Beauv. CoucH GRAss.
Open ground and grassland; frequent. June. Introduced from Eur. (Triticum
repens L.)
A troublesome weed on account of its creeping rootstocks. Also called quack,
quitch, and quick grass.

FLORA OF THE DISTRICT OF COLUMBIA. 91

52. SECALE L.

1. Secale cereale L. Rye,
Occasional along roads and in the vicinity of grain fields. June. Cultivated for
grain and forage; native of the Old World.

53. TRITICUM L.

1. Triticum aestivum L. WuHeat,
Vicinity of elevators and waste land where the seed has been accidentally scattered.
June. Not established in our flora. Native of the Old World. (T. vulgare Vill.)

54. HORDEUM L. Barley Grass.
Plants perennial.

Awns 4-5 cm. long.........2...-222-2-. 02222 e eee eee eee eee eee ee 1. H. jubatum.
Awns usually not over 1 cm. long ............2..--2--22--------- 2. H. nodosum.
Plants annual.
Glumes, at least some of them, ciliate.............................3. H. murinum.
Glumes not ciliate,
Awns as much as 10 cm. long; blades 5-10 mm. wide... ......... 4. H. vulgare.
Awns 1-1.5 cm. long; blades narrow.......-......--------+--+-- 5. H. pusillum.
1. Hordeum jubatum L. SQUIRRELTAIL GRASS.

Open ground; rare. July. Western U.S.; introduced in the eastern U. S.
2. Hordeum nodosum L.
Open dry ground; infrequent. June. Common in the western U. S.; also in
Eur. and Asia.
8. Hordeum murinum IL.
Waste places; rare. Introduced from Eur.
4. Hordeum vulgare L. BARLEY.
Along railroads and in waste places; occasional. June. Cultivated as a cereal;
native of the Old World.
5. Hordeum pusillum Nutt.
Open dry ground; rare; Canal Road (Steele). June. Western U. S.; sparingly
introduced in the eastern U. S.

55. ELYMUS L. WILD RYE.

Glumes subulate, not indurate at base, with about 2 strong nerves; culms slender.
Lemmas pubescent.............--- 2222220202 eee eee ee eee eee eee 1. E. striatus.
Lemmas glabrous..........2.-------- eee ee eee eee eee la, E, striatus arkansanus.

Glumes narrow but not subulate, indurate at base, about 5-nerved.

Spike nodding; awns curved-spreading; glumes divergent but not much bowed-out

At base... ccc cence eee nee eenee 2. E. canadensis.
Spike erect; awns straight; glumes bowed-out at base, the induration prominent.
Glumes and lemmas glabrous...............020.0200eeeceeees 3. E. virginicus.
Glumes and lemmas hirsute.
Awn not longer than the lemma.............. 3a. E. virginicus hirsutiglumis.
Awn long and somewhat spreading..............-.----+----- 4. E. australis.

1. Elymus striatus Willd.
Rocky woods; frequent. Summer. Northern states, south to Va.
la. Elymus striatus arkansanus (Scribn. & Ball) Hitchc.
Rocky woods; rare; along the Potomac above the fall line. Summer. Southern
states, north to Md.
2. Elymus canadensis L. WILD RYE.
Open low ground; rare; Fourmile Run (Dewey). July. Eastern U. §.

92 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

3. Elymus virginicus L. TERRELL GRASS.

Low ground and open woods; frequent. July. Eastern U.S.

A form with narrower, less distinctly howed-out glumes has been called F. glabriflo-
rus Scribn. & Ball.
3a. Elymus virginicus hirsutiglumis (Scribn.) Hitchc.

Moist places; rare; along the Potomac. Aug. Northern states, south to Va.
4. Elymus australis Scribn. & Ball.

Rocky woods; frequent above the fall line along the Potomac. July. Southern
states, north to Conn.

56. HYSTRIX Moench.

1. Hystrix patula Moench. BorrLE-BRUSH.
Rocky wooded slopes; frequent. July. Eastern U. 8S. (Gymnostichum hystrix
Schreb.; H. hystrix Millsp.)
The slender glaucous culms and pale, horizontally spreading spikelets stand out
against the dark background of the wooded slopes, forming a charming picture.

57. ARUNDINARIA Michx.

1. Arundinaria tecta (Walt.) Muhl. SMALL CANE.
Swamps or moist soil; near Ammendale, and beyond our limits between Washington
and Baltimore. Southern states, north to Md.

17, CYPERACEAE. Sedge Family.

Achene inclosed in a membranaceous sac (the perigynium). Flowers unisexual;
plants perennial........2.22.2.0.00..000200 0020 c cece cee eee 13. CAREX.
Achene not inclosed in a perigynium.
Flowers unisexual, the staminate and pistillate spikelets crowded in the same in-
florescence; achenes white, bony, globular...............2...... 12. SCLERIA.
Flowers perfect; achenes not bonelike.
Spikelets flat, the flowers 2-ranked.
Inflorescence axillary; achene beaked; bristles longer than the achene.
3. DULICHIUM.
Inflorescence terminal; achene beakless; bristles none.
Spikelets several to many-flowered.....................0.... 1. CYPERUS.
Spikelets 1-flowered, sessile in a small compact head or glomerule.
2. KYLLINGA.
Spikelets terete, the flowers spirally imbricate.
Spikelets with 1 or 2 beaked achenes. Bristles present..11. RYNCHOSPORA.
Spikelets with several to many achenes.
Culms leafless, terete or flattened; spikelet solitary, terminal.
, 4, ELEOCHARIS.
Culms leafy (the leaves sometimes bladeless); spikelets few to many, if solitary
the spikelet lateral.
Perianth of 1 or more flat scales; bristles present or wanting.
Achene and scales stipitate; bristles 3; plants perennial.9. FUIRENA.
Achene and solitary minute scale sessile; bristles wanting; minute
tufted annual........0..2.0.002.0.0.2020220 0000. 10. HEMICARPHA.
Perianth wanting or of bristles only.
Bristles wanting. Achenes minutely reticulate; inflorescence umbellate,
Achene with a minute tubercle, 3-angled; blades capillary.
5. STENOPHYLLUS.
Achene not tuberculate; blades flat or concave...6. FIMBRISTYLIS.
Bristles present. Plants perennial.
Bristles few (1-8), not long and silky, usually not exceeding the scales.
7. SCIRPUS.
Bristles numerous, long and silky, much exceeding the scales.
8. ERIOPHORUM.

FLORA OF THE DISTRICT OF COLUMBIA. 93

1. CYPERUS L.

Plants annual, tufted.
Achenes lenticular; stigmas 2. Rachilla narrow, continuous, the scales and achenes

deciduous; culms mostly less than 30 cm. tall.

Scale tips not appressed; spikelets not over 2 mm. wide..... 1. C. microdontus.
Scale tips appressed ; spikelets 2.5-3 mm. wide.
Scales reddish-tinged ; achenes dull brown, 1.2 mm. long....... 2. C. diandrus.

Scales yellowish; achenes shining black, less than 1 mm. long.8. C. flavescens.
Achenes 3-sided; stigmas 3.
‘Spikelets crowded on a very short axis, forming flabellate or round heads, these
solitary or in short-rayed umbels.
Scale tips acuminate, recurved.....................22---000-0- 4.C. aristatus.
Scale tips blunt, not recurved.................22222---020-00005 5. C. fuscus.
Spikelets pectinate on an elongate axis; umbel usually many-rayed.
Spikes 2-3 times as long as broad; rachilla continuous, the scales and achenes
deciduous... 2.220.020.0200. 2 eee eee ee eee eee 6. C. erythrorhizos.
Spikes about as broad as long; rachilla disarticulating, the achenes attached.
7. C. speciosus.
Plants perennial, hard and cormlike at base or stoloniferous.
Rachilla persistent after the fall of the scales and achenes.
Spikelets minute, not over 4mm. long, nearly as broad, ovate, crowded in dense
heads, these in long-rayed umbels.................... 8. C. pseudovegetus.
Spikelets usually 10 mm. long or more, linear.
Plants not stoloniferous; culms cormlike at base; spikelets in subglobose heads,
solitary or few...........2222 2-02-0222 eee eee ee eee eee 9. C. filiculmis.
Plants very smooth, almost waxy, stoloniferous, the stolons bearing hard tubers;
spikelets loosely pectinate.
Scales reddish chestnut; spikelets about 1.5mm. wide....... 10. C. rotundus.
Scales stramineous; spikelets about 1 mm. wide........-.- 11. C. esculentus.
Rachilla falling from the axis of the spike, either entire or disarticulating.
Spikelets strongly flattened. Umbels large, one-quarter to one-third the entire
height of the plant..........0..0..0...0..0.00...0.2.2220005- 12. C. strigosus.
Spikelets subterete or but slightly flattened.
Spikelets radiate, in dense subglobose or short-cylindric heads, few-flowered,

bluntish.
Heads globose or subglobose..............2..-2.2.-----+--- 13. C. ovularis.
Heads short-cylindric .. 2.222.222 eee ee 14. C. torreyi.

Spikelets reflexed, in cylindric or turbinate heads, sharp-pointed.
Heads turbinate, the spikelets sharply reflexed; culms scabrous below the

umbel.

Basal leaves nearly as long as the culm; heads usually 2.5-3 cm. long,

the base attenuate..............00......0...02. 15. C. dipsaciformis.
Basal leaves much shorter than the culm; heads not over 2 cm. long, short-

turbinate........-...2.-.0---2-2220 2-2 eee eee eee 16. C. retrofractus.

Heads subcylindric; culms smooth.

Spikelets crowded..............-2.2+-2------------ 17. C. lancastriensis.
Spikelets not crowded.................0..0.02020005 ....18. C. refractus.

1. Cyperus microdontus Torr.

Wet sand and alluvium near streams; Bladensburg, Kenilworth, Hyattsville, and
eastward; frequent. Aug.—Oct. Atlantic Coastal Plain. (C. nuttallai of Ward’s
Flora.)

2. Cyperus diandrus Torr.

Margins of ponds and streams; Chevy Chase Lake, Eastern Branch, and southward;
frequent. July-Sept. Eastern and middle states. (C. diandrus castaneus of
Ward’s Flora.)

94 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

8. Cyperus flavescens L.

Wet banks and springy places; along Piney Branch, Rock Creek, Eastern Branch,
and Potomac; frequent. July-Oct. Eastern U. 8.

4. Cyperus aristatus Rottb.

Alluvial and sandy flats; flood plain of Rock Creek and the Potomac. July-Sept.
Throughout the U. 8. (C. inflexus Muhl.)

Dried specimens have the odor of slippery elm.

5. Cyperus fuscus L.

Adventive in wet waste ground near wharves; Washington and Alexandria; ap-
parently infrequent, Aug.—Sept. Ballast grounds of Atlantic ports; European.
6. Cyperus erythrorhizos Muhl.

Common in alluvial flats in the wet sandy flood plain of the Potomac below
Washington. Eastern and middle states.

On ground which becomes dry in late summer the plants form dwarf tufts; this
form is the variety pumilus Engelm.

7. Cyperus speciosus Vahl.

Sandy margins of streams; common along the Potomac south of Washington, infre-
quent to the east, not found in the northwest. Aug.-Oct. Eastern and middle
states. (C. michauxianus Schult.; included in C. ferar Rich. in Gray’s Manual.)
8. Cyperus pseudovegetus Steud.

Frequent in alluvial soil among rocks; margin of the Potomac from Great Falls to
below Washington. July-Sept. Atlantic and Gulf coasts, also in Kans. and Mo.
(C. virens of Ward’s Flora.)

9. Cyperus filiculmis Vahl.

Common in dry sandy open ground and open pine woods. June-Sept. Eastern
and middle states.

10. Cyperus rotundus L. NUT GRASS.

Found in 1899 in waste ground west of the old fishpond. Oct. Atlantic and Gulf
states; abundant and often a troublesome weed in the South.

11. Cyperus esculentus L.

Common in low wet waste ground, especially along the Potomac. July—Oct.
Throughout the U.S. (C. phymatodes Muhl.)

12. Cyperus strigosus L.

Common in alluvial ground near streams, everywhere. Aug.—Oct. Throughout
the U.S.

18. Cyperus ovularis (Michx.) Torr.

Dry sandy wood borders and old fields; frequent.throughout. July-Sept. Atlantic
and middle western states.
14. Cyperus torreyi Britton.

Rare; found in a low field at Bennings. July-Sept. Atlantic Coastal Plain. (C.
eylindricus Britton, not Boeckl.) .

15. Cyperus dipsaciformis Fernald.

Dry sandy woods; frequent. July—Sept. N. J. and southward, and in Ky. (in-
cluded in C. retrofractus in Britt. & Brown, Illustr. F1.)
16. Cyperus retrofractus (L.) Torr.

Dry sandy or rocky soil; Munger’s Hill. Oct. Atlantic Coastal Plain and in the
lower Mississippi Valley,

17, Cyperus lancastriensis Porter,

Common in low, sandy or gravelly, open ground along the Potomac. July—Oct.
Middle Atlantic states.

18. Cyperus refractus Engelm.

Common in dry wood borders and banks along Rock Creek, Eastern Branch, and
Potomac. N. J. to Ga.and Mo.

FLORA OF THE DISTRICT OF COLUMBIA, 95

2. KYLLINGA Rottb.

1. Kyllinga pumila Michx.
Holmead Swamp (Waite). Coastal Plain.

3. DULICHIUM L. Rich.

1. Dulichium arundinaceum (L.) Britton.
In sluggish water bordering streams and ponds; frequent, especially along the
Potomac. July-Oct. Throughout the U.S. (D. spathaceum Pers.)

4. ELEOCHARIS R. Br. SriKE RUSH.

Spikelets not thicker than the spongy 4-angled culm. An aquatic, about 1 meter tall.

. . 10. E. quadrangulata.
Spikelets much thicker than the culm.

Achenes 3-angled; stigmas 3.
Culms capillary, 3-12 cm. tall (elongate when submerged)....... 1. E. acicularis.
Culms slender but not capillary.
Plants perennial, with running rootstocks.

Culms 4-angled, very slender; scales reddish chestnut......... 2. E. capitata.
Culms flattened; scales fuscous...............00c0eeeeeeee 8. E. acuminata.
Plants annual, tufted, without rootstocks. Achene reticulate, its tubercle
nearly as large as the body ................0.02220000-- 4. E, tuberculosa.

Achenes biconvex; stigmas 2.

Plants rarely over 10 cm. tall, annual; upper sheaths with loose pale scarious tips.
Spikelets dark, the scales purple-brown, with green midribs ....5. E. olivacea.
Spikelets pale, the scales whitish.............. .6. E. flaccida.

Plants mostly more than 20 em. tall (10-20 in LE. engelmanni); upper sheaths with

close firm dark-margined tips.
Plants perennial, with creeping rootstocks...................- 9. E. palustris.
Plants annual, densely tufted.

Spikelets cylindric, tapering at the apex, commonly | cm. long; bristles

about equaling the achene.......................... 7. E, engelmanni.
Spikelets ovoid or ovoid-oblong, blunt, rarely over 8 mm. long; bristles
exceeding the achene......................0.---------00- 8. E. obtusa.

1. Eleocharis acicularis (L.) Roem. & Schult.

Mud flats and shallow water along Piney Branch and the Potomac at Chain Bridge.
July-Sept. Throughout the U.S.

Plants perennial by delicate capillary rootstocks.

2. Eleocharis capitata (L.) R. Br. .

Moist open ground; Takoma Park and eastward; infrequent. Eastern U.S. (EF.
tenuis Schult.)

This species was originally described from Virginia as Scirpus capitatus. The culm
is described as terete and the spike as subglobose, but Dr. Blake, who has examined
the specimen in the British Museum, finds these statements to be erroneous, the plant
being the one with 4-angled culms and narrowly ovoid spikelets later named L. tenuis.!
3. Eleocharis acuminata (Muhl.) Nees,

Moist open ground along the Potomac; frequent. May-June. Eastern states, north
to N. Y. (E. compressa Sulliv.)

4. Eleocharis tuberculosa (Michx.) Roem. & Schult.

Sandy bogs; vicinity of Brightwood; Holmead Swamp; Howard University

reservoir. July-Sept. Atlantic states.

'See Blake, 8. F., Notes on the Clayton Herbarium. Rhodora 20: 23. 1918.

96 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

5, Eleocharis olivacea Torr.

Boggy soil; Holmead Swamp and about the reservoir near Howard University.
July-Sept. Me. to N.C. and Mich.
6. Eleocharis flaccida (Reichenb.) Urban.

In shallow water and mud flats; Hunting Creek. Coastal Plain from N. J. south-
ward. (E. ochreata Steud.)
7. Eleocharis engelmanni Steud.

Muddy ground; south of Washington; infrequent. June-Aug. Mass. to Mo.
8. Eleocharis obtusa (Willd.) Schult.

Mud flats and moist stream borders; common, especially to the east and south.
May-Sept. Eastern and northern U. 8.
9. Eleocharis palustris (L.) Roem. & Schult.

In shallow water or open marshy ground; Fourmile Run; Dyke; Ead’s Mill; op-
posite Alexandria. May-July. Throughout the U. S.
9a. Eleocharis palustris glaucescens (Willd.) A. Gray.

Alluvial flats; infrequent; Little Falls and southward. May-June. Throughout the
U.S.

More slender than the species.
10. Eleocharis quadrangulata (Michx.) Roem. & Schult.

In shallow water; along Eastern Branch; rare. July-Sept. Eastern and middle
states. (FE. mutata of Britt. & Brown, Illustr. Fl.)

5. STENOPHYLLUS Ral.

1. Stenophyllus capillaris (L.) Britton.
Common in sandy open ground and fields. July-Sept. Throughout the U. 8.
(Fimbristylis capillaris A. Gray.)

6. FIMBRISTYLIS Vahl.

Achenes triangular, smooth; umbel decompound............--- 1. F. mucronulata.
Achenes lenticular, strongly reticulate; umbel simple or nearly so. .2. F. baldwiniana.

1. Fimbristylis mucronulata (Michx.) Blake.

Common in low, moist, sandy or alluvial soil, mostly nearstreams, July-Oct. East-
ern U.S. (F. autumnalis of authors, not Roem. & Schult.)
2. Fimbristylis baldwiniana Torr.

Alluvium; Great Falls, Maryland. Aug. Atlantic Coastal Plain and lower Missis-
sippi Valley. (Included in F. Jara in Gray’s Manual.)

7. SCIRPUS L.

Involucral bract 1, appearing like a continuation of the culm, or wanting.
Involucral bract wanting; spikelets solitary. Plants leafy, densely tufted, perennial,

15-20 cm. tall........22 20.2.0 ee eee eee 1. S. planifolius.
Involucral bract developed, erect; spikelets 2 to many, rarely 1.
, Culms sharply 3-angled; 2 or 3 leaf blades well developed . .....4. S. americanus.

Culms terete; sheaths bladeless.
Plants annual, slender, rarely 50 cm. tall; spikelets 1-6, in a close head.
Achenes turgid, biconvex; bristles 6, barbed, about equaling the achene.
2. S. debilis.
Achenes plano-convex; bristles 1 or 2 smooth rudiments or none.
3. S. smithii.
Plants perennial, robust, commonly 2 meters tall; spikelets numerous, in a
drooping umbel...................2..--055- Lecce eee eee eee 5. S. validus.

FLORA OF THE DISTRICT OF COLUMBIA. 97

Involucral bracts several, foliaceous. Culms 3-angled, leafy; plants perennial.
Spikelets large, about 2 cm. long at maturity, ovate. Scales awn-tipped.

Achenes sharply 3-angled; spikelets numerous, in a compound umbel.
6. S. fluviatilis.
Achenes plano-convex; spikelets few to several, in simple or nearly simple umbels.
7. S. robustus.

Spikelets not over 8 mm. long, very numerous, in decompound umbels.
Spikelets pedicellate, in loose clusters in large drooping panicles, or if in dense

glomerules the spikelets woolly from the long smooth delicate bristles.

Spikelets cylindric, 6-8 mm. long, in loose panicles; bristles not exserted

beyond the scales..............----- 22-22 e eee eee eee eee 8. S. lineatus.
Spikelets ovate or subglobose, not over 5 mm. long, woolly from the exserted
bristles.
Spikelets mostly in glomerules of 3-5.
Glomerules not congested in dense heads..........-------- 9. S. cyperinus.
Glomerules congested in dense heads......- 9a. S. cyperinus condensatus.

Spikelets solitary, or in small clusters with pedicellate lateral spikelets.
10. S. eriophorum.
Spikelets sessile (not over 5 mm. long), in dense glomerules, these in stiff-rayed
decompound umbels; bristles shorter than the scales.
Spikelets ruddy brown, commonly proliferous. Bristles flexuous, much longer
than the achenes.........-....- cence esc e cen eenceeee 11. S. polyphyllus.
Spikelets olive or greenish brown.
Spikelets 3-8 in each glomerule; umbel loose and drooping.
12. S. sylvaticus.
Spikelets several to many, in dense glomerules; rays of the umbel stiff.
Sheaths and often the leaves nodulose; bristles as long as the achenes.
13. S. atrovirens.
Sheaths not nodulose; bristles short or wanting......-.. 14. S. georgianus.

1. Scirpus planifolius Muhl.
Rocky woods; common from Cleveland Park north and west and along Sligo Creek,
below Takoma Park. Apr.—June. Vt. to Md. and Mo.
2. Scirpus debilis Pursh.
Wet sandy open ground and mud flats; frequent near the Eastern Branch and
Potomac; also at Terra Cotta. July-Sept. Eastern U. 8.
8. Scirpus smithii A. Gray.
Wet shores; beach of Hunting Creek, near Alexandria. July-Sept. Me. to Va. and
Mich.
4. Scirpus americanus Pers.
Open marshy ground in the flood plain of the Potomac, from Long Bridge south-
ward; infrequent. June-Oct. Throughout the U. 8. (S. pungens Vahl.)
5. Scirpus validus Vahl. BULRUSH.
Marshes and shallow water in the flood plain of the Eastern Branch and Potomac,
forming a pure growth; infrequent. June-July. Throughout the U. 8.
6. Scirpus fluviatilis (Torr.) A. Gray. RIvER CLUB RUSH.
Marshes; near the mouth of Eastern Branch and at Dyke. June-July. Northern
states, south to Va.
7%. Scirpus robustus Pursh.
Marshes along the Potomac below Alexandria; ‘‘Maltox Creek.” June. Atlantic
Coastal Plain.
8. Scirpus lineatus Michx.
Swales and moist wood borders; frequent along the Potomac. June. Eastern U.S.

69289—19 7

98 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

9. Scirpus cyperinus (L.) Kunth. Woo. GRASS.

Swales and wet meadows; common, especially in the southern and eastern part of
ourrange. Aug.-Sept. Atlantic coast to Tenn. and Ark.
9a. Scirpus cyperinus condensatus Fernald.

Swales and open meadows; Riverdale and Lanham. Sept. Northern Atlantic
states.

10. Scirpus eriophorum Michx.

Swales and among openings along streams; common. July-Sept. Atlantic states
and lower Mississippi Valley. July-Sept. (Included in S. cyperinus in Britt. &
Brown, Illustr. Fl.)

11. Scirpus polyphyllus Vahl.

Swales, ditches, and wet wood borders; common. July-Oct. Eastern U. 8.

Often conspicuously proliferous in the autumn, the inflorescence bearing few to
several well-developed leafy plantlets, the culms leaning, bringing the plantlets
near the earth. A form with spikelets as much as 5mm. long has been called S.
polyphyllus macrostachys Boeck}.

12. Scirpus sylvaticus L.

Marshes along the Eastern Branch; rare. Aug. Eastern U. 8.
13. Scirpus atrovirens Muhl.

Swales, ditches, and wet wood borders; common along the Potomac. June-Aug.
Northern states, south to Ga.

14. Scirpus georgianus Harper.

Wet sandy and alluvial soil in the flood plain of the Potomac at Long Bridge and
southward. June-July. Northern states, south to Ga. (Included in 8. atrovirens in
Britt, & Brown, Illustr. F1.) .

8. ERIOPHORUM L. Corron Grass.
1. Eriophorum virginicum L.
Open ground in magnolia bogs; Terra Cotta and eastward; infrequent. July-Sept.

Northern states, south to Ga.

9. FUIRENA Rottb.

1. Fuirena hispida Ell.

Frequent in open ground in magnolia bogs below the fallline. Aug.-Sept. Southern
states, north to N. J.

Ator after maturity producing ovate tubers close to the base of the culm.

10. HEMICARPHA Nees & Arn,

1. Hemicarpha micrantha (Vahl) Pax.
Open wet sandy ground; Zoological Park and Potomac bottom land near Lock No.
9. Sept. Throughout the U.S.

11. RYNCHOSPORA Vahl.

Achene bearing a beak 2-3 times its own length, the two together about 2 cm. long.
Spikelets in large squarrose heads.
Bristles shorter than the body of the achene: heads rather loose. ..1. B.-corniculata.
Bristles about twice as long as the body of the achene; heads compact.
2. R. macrostachya.
Achene bearing a small tubercle or beak much shorter than the body, the two together
not over 8 mm. long.
Achene transversely wrinkled ; bristles not over half the length of the achene.
3. R. cymosa,

FLORA OF THE DISTRICT OF COLUMBIA. 99

Achene smooth: bristles longer than the achene.

Spikelets whitish or pale brown, in small dense cymose heads........ 4. R. alba.
Spikelets dark brown.
Spikelets in dense globose heads...........----+-----++++e50-55 5. R. axillaris.
Spikelets in broad or narrow cymose heads.
Achene ovoid, 1.2 mm. wide, rounded at base..---.----- 6. R. gracilenta.
Achene obovoid, 0.8 mm. wide, with distinct spikelike base.
Bristles downwardly barbed.........--.--------++----- 7. BR. capitellata.
Bristles upwardly barbed......-...------ 7a. R. capitellata controversa.

1. Rynchospora corniculata (Lam.) A. Gray.

Wet sand by the Potomac at Sandy Landing, Maryland, below Great Falls; collected
but once. Sept. Coastal Plain, Del. southward.
2. Rynchospora macrostachya Torr.

Marshes along the lower part of the Eastern Branch and near Accotink Creek; infre-
quent. Aug.-Sept. Atlantic states and occasionally inland. (Included in R. corni-
culata in Britt. & Brown, Ilustr. FI.)

3. Rynchospora cymosa Ell.

Swales; Kenilworth and Lakeland. June-July. Southeastern states, north to N. J.
4. Rynchospora alba (L.) Vahl.

Open places in magnolia bogs below the fall line; frequent. July-Sept. Through-
out the U.S. .

5. Rynchospora axillaris (Lam.) Britton.

Among sphagnum in East Hyattsville Swamp. Aug.—Sept. Atlantic Coastal Plain.
6. Rynchospora gracilenta A. Gray.

Bogs below the fall line; small bog east of Brookland. Aug.-Sept. Atlantic
Coastal Plain.

%. Rynchospora capitellata (Michx.) Vahl.

Swales and wet spots in woods; frequent. Eastern U.S. (R. glomerata of authors.)
"a. Rynchospora capitellata controversa Blake.

Wet ground; Holmead Swamp; near Aqueduct Bridge. Aug.-Sept. Pa. to Va.

There is a specimen of R. fusca (L.) Ait., labeled “near Washington, D. C., Dr.
Geo. Vasey.” The locality is doubtful.

12. SCLERIA Berg. NvtT RUSH.

Achenes smooth, white and shining.
Culms commonly about 1 meter tall; achene globose.....-..---- 1. S. triglomeratea.
Culms usually not over 50 cm. tall; achene ovate......--------+--: 2. S. oligantha.
Achenes reticulate or papillose.
Achenes reticulate; fascicles of spikelets few to several in a small panicle; axil-
lary fascicles slender-peduncled......------++++--+-++++2++- 4. 8. reticularis.
Achenes papillose; fascicles of spikelets few, approximate; axillary fascicles, if pres-
ent, subsessile.

Foliage glabrous.......---..02+eeeee seer errr ceteerr sree ress 3. S. pauciflora..
Foliage pubescent. ...-.----------+ secre rect eeree 3a. S. pauciflora caroliniana.

1. Scleria triglomerata Michx.
Wet sandy woods and swales; Terra Cotta and southeastward, below the fall line;
frequent. June. Eastern U.S.

2. Scleria oligantha Michx.
Sandy woods; represented by a single collection by Vasey labeled ‘‘Washington,

D. C., 1874.” The specimen cited by Ward as collected at ‘Rock Creek above Davis’s
Quarry, June, 1874 (Dr. Vasey)” can not be found, unless the above specimen lacking
data be it. June-Aug. Southern Atlantic Coastal Plain to Tex.

100 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

3. Scleria pauciflora Muhl.

Sandy woods; frequent above the fall line. May-July. Southern states, north to
N. J.
3a. Scleria pauciflora caroliniana (Willd.) Wood.

Sandy field, east of Bennings. July. Eastern U. S., rare and local.
4. Scleria reticularis Michx.

Wet sandy open ground and magnolia swamps; Chevy Chase and eastward, mostly
below the fall line; frequent; associated with sphagnum and Panicum lucidum. Aug.-
Sept. Atlantic Coastal Plain and at the head of Lake Michigan.

13. CAREX L. SEDGE.

Complete specimens with mature fruit are necessary for the identification of species
in this genus. Diagnostic characters are found mainly in the shape, size, and texture
of the perigynium (the sac-like body inclosing the achene); in the shape of the achene
and the number of stigmas; in the relative position of the pistillate and staminate
flowers (the latter usually represented in mature plants only by empty scales or, occa-
sionally, by filaments); in the presence or absence of sheaths on the lower bracts of
the culm; and in the appearance of the rootstocks.

Achenes lenticular; stigmas 2!..............-..--2-2-------- Subgenus I. VIGNEA.
Achenes trigonous: stigmas 3.................--. Leeeeeee Subgenus II. EUCAREX.

Subgenus I. VIGNEA (Beauy.) Nees.

Staminate and pistillate flowers on the same spike (C. bromoides sometimes dioe-
cious); lateral spikes sessile.

Staminate flowers above the pistillate.
Spikes usually 10 or fewer, green when mature (C. muricata has purplish-tinged
SCal@S). 0... ee ee eee cee eee e cece eens 1. Muhlenbergianae.
Spikes usually more numerous, yellowish or tawny when mature.

Beak of perigynium equaling or shorter than the body, the base not spongy.
Perigynia papery, green to dull brown ............ eee eeeeeeee 2. Multiflorae.
Perigynia hard, shiny brown...........-.--.---.--.-----+-2++--- 8. Paniculatae.

Beak of perigynium much exceeding the body, the base spongy.

4. Stenorhynchae.
Staminate flowers below, or occasionally intermixed with, the pistillate.
Perigynia not wing-margined, at most thin on the margin and then spongy at base.

Base of perigynium not spongy, the margin not thin.

Spikes short, obovoid; beak of perigynium very short, obscure.
5. Canescentes.
Spikes long, lance-cylindric; beak of perigynium fully half as long as the body.
6. Deweyanae.
Base of perig ynium spongy, the margins thin.....................- 7. Elongatae.
Perigynia wing-margined, not spongy at base. Spikes ovoid........... 8. Ovales.

Subgenus Il. EUCAREX Coss. & Germ.

One or more spikes strictly pistillate (except in C. leptalea and C. typhina, and
sometimes in C. squarrosa), the terminal commonly staminate, the lateral often
peduneulate.

Achenes lenticular; stigmas 2.2.2.2 ..0..200.. 0.000.020 eee eee eee eee eee 9. Acutae.

1 Six of our species of Hucarex have lenticular achenes and two stigmas. They are
readily distinguished from the Vigneae by their having one or more spikes strictly
staminate or nearly so. See key to Eucarez.

FLORA OF THE DISTRICT OF COLUMBIA. 101

Achenes trigonous; stigmas 3.
Perigynia beakless or, if beaked, without rigid teeth.
Lower bracts of the inflorescence without conspicuous green sheaths.

Spikes solitary, terminal.
Perigynia beakless; scales short, hyaline...........--- 10. Polytrichoideae.
Perigynia long-beaked; scales long, bractlike...........-- 11. Phyllostachyae.

Spikes 2 or more.
Terminal spike entirely staminate.

Perigynia pubescent.
Leaves and culms glabrous.

Culms leafy (C. vestita)...........2.-- 2+ +22 eee eee eee eee 24. Hirtae.
Culms not leafy.............--- 2-22-22 eee eee ee eee eee 12. Montanae.
Leaves and culms pubescent...........-- wee ewer ees 13. Pubescentes.

Perigynia glabrous.
Spikes stout, sessile or short-peduncled; perigynia nerved.
14. Pallescentes.
Spikes slender, drooping on slender peduncles; perigynia nerveless (C.
PVASINA) . 2.2.2 eee eee eee ee eee ee ee eee eens 18. Gracillimae.
Terminal spike partly pistillate.
Perigynia nerveless except on the margins.

Spikes drooping; perigynia ascending (C. prasina)...... 18. Gracillimae.
Spikes erect; perigynia reflexed.......-..---------++--+ 15. Shortianae.
Perigynia nerved..........-------- 002s cece ee eee eee ee eee 16. Virescen tes.

Lower bracts of the inflorescence with conspicuous green sheaths.
Perigynia nerveless or with few nerves thicker at the base.
Spikes slender, drooping.

Perigynia long-beaked ........---------20- eee eee eee eee eee 17. Debiles.
Perigynia short-beaked........----------+-eeee eee eee eee 18. Gracillimae.
Spikes stouter, ascending......---...-------- eee eee eee eee eee 19. Paniceae.
Perigynia with many uniform nerves.
Nerves impressed .........-.02 0-0 cece eee cece eect eee eee eeeees 20. Griseae.
Nerves elevated.
Perigynia trigonous in cross section........-----+-+---+--++- 21. Laxiflorae.
Perigynia circular in cross section.
Spikes slender, drooping (C. oblita)........---------+++++ 17. Debiles.
Spikes stouter, ascending or divaricate.......-.-------- 22. Granulares,

Perigynia rigidly bidentate, the teeth sharp.
Achenes closely enveloped by the usually firm and tough perigynia.
Nerves of the perigynia few or none.

Perigynia reflexed.......-.----- 2-2 eee eee ee eee eee eee ee eres 23. Flavae.
Perigynia ascending.............2.2..2 00.2222 e eee ee eee eee eee 24, Hirtae.
Nerves of the perigynia numerous (15-30).........--..-----25, Pseudocyperae.
Achenes loosely enveloped by the thin papery perigynia......-- 26. Physocarpae.

1. Muhlenbergianae Tuckerm.

Inflorescence comparatively short, usually green when mature.

Spikes loosely flowered, delicate; perigynia spongy below the middle.

Spikes approximate or nearly so; beak of perigynium smooth; scales acuminate.

1. C. retroflexa.
Spikes mostly remote; beak of perigynium minutely roughened; scales blunt.

Perigynium broadly lanceolate, sharply contracted into the flat beak; stigmas
dark brown, thick, twisted............--..-------- eee eee 2. C. convoluta.
Perigynium narrowly lanceolate, slightly contracted into the nearly terete beak;
stigmas light brown, slender, straight............-----------+-- 8. C. rosea.

102 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Spikes densely flowered, much coarser; perigynia not spongy below the middle
(except in C. conjuncta).
Leaves less than 4.5 mm. broad; sheaths tight, often thickened at the mouth (sheaths
loose in C. aggregata).
Scales tinged with reddish purple; perigynia 4-6.5 mm. long....4. C. muricata.
Scales greenish or nearly hyaline; perigynia shorter.
Heads 25-40 mm. long; lower spikes distinct (except in C. aggregata).
Sheaths tight; beak of perigynium half as long as the body.
5. C. muhlenbergii.

Sheaths loose; beak of perigynium equaling the body...... 9. C. aggregata,
Heads 10-20 mm. long; lower spikes not distinct.
Scale body equaling the broadly ovate perigynium....... 6. C. mésochorea.

Scale body much shorter than the perigynium,
Perigynium narrow at the base; leaves 2-4.5 mm. wide.
7. C. cephalophora.
Perigynium broad at the base, cordate or nearly so; leaves 0.7-2 mm. wide.
8. C. leavenworthii.
Leaves more than 4.5 mm. broad (usually narrower in C. aggregata); sheaths loose,
membranaceous.
Culms sharply triangular, not winged; perigynium not spongy bélow the middle.
* Lower spikes not separate; only the broadest leaves, if any, over 4.25 mm.
broad... 2.2.22... 2 eee eee eee neces 9. C. aggregata.
Lower spikes widely separate; leaves mostly 5 mm. broad or more.
10. C. sparganioides.
Culms narrowly winged; perigynium slightly spongy below the middle.
11. C. conjuncta.

2. Multiflorae Kunth.

Represented by only 2 species in our region. Conspicuous by its many-flowered,
often somewhat compound heads, dense, dull brown or yellow-brown spikes, and
numerous setaceous bracts.

Leaves longer than the culm; beak of perigynium equaling the body.
12. C. vulpinoidea.
Leaves shorter than the culm; beak of perigynium much shorter than the body.
13. C. annectens.

3. Paniculatae Kunth.
Heavy-headed plants, superficially resembling Echinochloa crusgalli.

A single species. ....... 2.2.2... c cece cece cee ee eee eee eeee 14. C. decomposita.

4. Stenorhynchae Holm.

Two closely allied species are found here, somewhat resembling the coarser-
headed species of the Muhlenbergianae, but the long-beaked awl-shaped perigynia,
with very corky bases, are very distinct from any in that group.

Sheaths wrinkled, loose at the mouth................ ccc e eee ee ee eeee 15. C. stipata.
Sheaths not wrinkled, tight at the mouth..................... 16. C. laevivaginata.
5. Canescentes Fries,

Plants pale green, somewhat glaucous.

Asingle species..........0.. 20... ccc eee e eee cece cee ee eeeeeeees 17. C. canescens.

FLORA OF THE DISTRICT OF COLUMBIA. 103

6. Deweyanae Tuckerm.
Sometimes united with the following séction.
A single species... 2.2... 2.22.2. eee e ee eee eee ee ceeeee tere reece ceeees 18. C, bromoides.

7. Elongatae Kunth.

Spikes comparatively few-flowered; perigynia usually radiate or reflexed; stami-
nate flowers mostly below the pistillate. Closely allied species, growing usually in
wet woods, borders of ponds, or other locations where the soil is fairly moist throughout
the season.

Perigynium broadest near the middle, conspicuously nerved; beak short and smooth.
19. C, rosaeoides.
Perigynium broadest near the base; beak serrulate.
Beak of perigynium half as long as the body, sharply toothed. Scales acutish to
acuminate.
Leaves 1 mm. wide or more, usually shorter than the culm; perigynia ovate.
20. C. cephalantha.
Leaves less than 1 mm. wide, much longer than the culm; perigynia lanceolate.
20a. C. angustior.
Beak of perigynium not more than one-third as long as the body, thin-toothed.
Scales usually acute to acuminate; beak of perigynium about one-third as long as
the body...... 222-22 eee cece eee e eee eee eee ee eee e eee 21. C. incomperta.
Scales usually obtuse to slightly acute; beak of perigynium very short.”
Leaves 1-2 mm. broad, shorter than the culm; perigynium nearly or quite nerve-

less on the inner side...............20 22-22 - eee ee eee eee 22. C. interior.
Leaves natrower, usually much longer than the culm; perigynium strongly
nerved on the inner side .....-.......----+---- eee eee eee 23. C. howei.

8. Ovales Kunth.

Spikes ovate, dense, usually tawny; perigynia wing-margined; staminate flowers
always below. Perhaps the most distinct section of the Vigneae, certainly the most
complex.

Perigynia narrowly to broadly lanceolate, at least two and one-half times as long as
broad, much exceeding the scales.
Leaves at most 3 mm. wide, those of the sterile shoots few, ascending; spikes glossy
brown or straw-colored, pointed...........--------------+-++- 24. C. scoparia.
Leaves wider, those of the sterile shoots very numerous, widely spreading; spikes
green or dull brown, blunt.
Tips of perigynia appressed or ascending; spikes 7-12 mm. long.
25. C. tribuloides.
Tips of perigynia widely spreading or recurved; spikes 4-8 mm. long.
Inflorescence flexuous, elongate; culm weak, slender.......-... 26. C. projecta.
Inflorescence compact, oblong; culm stiff................- 27. C. cristatella.
Perigynia narrowly ovate to suborbicular or obovate, not more than twice as long as
broad, often equaled or exceeded by the scales.
Perigynia 3-4 mm. long, nerveless or finely nerved on the inner face.
Spikes gray-green when mature. Scales usually obtuse. ...28. C. albolutescens.
Spikes straw-colored or brownish when mature.
Hyaline portion of sheath very short; scales hyaline, with a conspicuous green
stripe on each side of the midrib............--.--------- 29. C. straminea.
Hyaline portion of sheath longer; scales tinged with reddish brown, without
green stripes. .... 2... cece eee eee eee eee eee eee 30. C. festucacea.

104 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Perigynia 4 mm. long or more, often strongly nerved on the inner face.
Scales obtuse or, at most, acutish. Spikes straw-colored or ferruginous.
31. C. brevior.
Scales long-acuminate or aristate.
Inflorescence stiff; spikes green or dull brown; perigynia obovate, abruptly

narrowed at the base...-. 2... 22... 22... e cece eee eee eee eee eee 32. C. alata.
Inflorescence flexuous; spikes becoming dark brown; perigynia suborbicular,
abruptly slender-beaked ....................2-2204- 33. C. hormathodes.

9. Acutae Fries.

Marsh, swamp, or bog plants, common in low grounds and along streams throughout
the region.

Scales long-aristate; achenes strongly constricted at the middle.
Sheaths glabrous; lower pistillate scales abruptly long-awned....... 34. C. crinita.
Sheaths rough-hispid; lower pistillate scales tapering into the awn. .35. C. gynandra.
Scales obtuse to acuminate; achenes not constricted.
Beak of mature perigynium twisted when dry...............-...... 86. C. torta.
Beak not twisted.
Culms densely cespitose, forming tufts; stolons inconspicuous; sheaths strongly

filamentose... 2.2.2... 2 2. ee eee cece e eee ee eeee 37. C. stricta.
Culms forming loose beds; stolons long and conspicuous; sheaths at most slightly
filamentose.
Mature perigynia straw-colored, few-nerved.................-.- 38. C. emoryi.
Mature perigynia green, nerveless....................-004- . 89. C. aquatilis.

10. Polytrichoideae Tuckerm.
A characteristic bog plant (placed by Kiikenthal in the subgenus Primocarez).
A single species.................-.- ee 40. C. leptalea.
11. Phyllostachyae Tuckerm.

Scales bractlike, almost or quite enveloping the perigynia,

Perigynia somewhat 2-edged, oblong; pistillate flowers usually 3-10; leaves pale

green, 1.5-4 mm, wide...................0.2 eee eee e eee ee 41. C. willdenovii.
Perigynia globose, with long slender beaks; pistillate flowers usually 1-3; leaves
darker, 1-2 mm. wide.................. cece eee cece eee eeeeeee 42. C, jamesii.

12. Montanae Fries.

Low plants with small heads, usually in dry soil of wooded or open banks; in
this region the earliest to mature.

Culms short, many of them hidden among the leaf bases.

Scales purplish black on each side of the midrib............ 43. C. nigromarginata.
Scales green, with lighter or hyaline margins.....................2.2-. 44. C. tonsa.
Culms long, none of them hidden among the leaf bases,
Plants not stoloniferous; leaves 2-4 mm. wide...........-...----- 45. C, communis.
Plants stoloniferous; leaves 0.5-3 mm. wide.
Stolons short, tawny-fibrillose; plants light green............. 46. C. emmonsii.

Stolons long, strongly red-fibrillose; plants dark green....47. C. pennsylvanica.

18. Pubescentes Kiikenth.

Plants pubescent throughout; terminal spike strictly staminate.

A single species.....................222222.. Leeeeeee eee cece eens 48. C. hirtifolia.

FLORA OF THE DISTRICT OF COLUMBIA. 105

14, Pallescentes Fries.

Plant glabrous; staminate spike terminal; pistillate spikes short and stout; perigy-
nia ascending.

A single species...........---2-- 0 cece eee e cence cence eee eeneee ...49. C. pallescens.
15. Shortianae Bailey.

Spikes brown, evenly cylindric, the tips of the densely crowded perigynia re-
curved and without teeth. .

A single species......... Lecce cece ence e cece e eee eeceneeeeeeeeeee 50. C. shortiana.
16. Virescentes Kunth.

Leaves long and slender, the sheaths, at least, hairy; terminal spike staminate
below; lower bracts of the inflorescence without conspicuous green sheaths.

Perigynia densely pubescent. ;
Terminal spike 9-18 mm. long; leaves usually exceeding the culms. ..51. C. swanii.
Terminal spike 18-40 mm. long; leaves usually shorter than the culms.

52. C. virescens.

Perigynia glabrous (at least at maturity).

Leaves (except sheaths) glabrous...........--..---------+-+- 53. C. caroliniana.
Leaves pubescent.
Scales acute to short-cuspidate, shorter than the perigynia; staminate portion

of terminal spike short.......-......---------- eee eee 54. C. complanata.
Scales rough-cuspidate, usually much longer than the perigynia; staminate por-
tion longer... 2.22.2... eee eee eee eee eee eee eeeee 55. C. bushii,

17. Debiles Carey.

Habit very lax; base of the lowest bract of the inflorescence long-sheathing; spikes
slender, drooping; perigynia thin-toothed, more or less long-beaked.

Perigynia lightly nerved or nerveless; upper sheaths glabrous.........- 56. C. debilis.
Perigynia strongly nerved; upper sheaths puberulent.............----- 57. C. oblita.
18. Gracillimae Carey.

Perigynia short-beaked, few-nerved, in long drooping spikes; lowest bracts of the
inflorescence sheathing.

Leaves glabrous; perigynia less than 2 mm. thick.

Lower bracts of the inflorescence long-sheathing..............-- 58. C. gracillima.
Lower bracts short-sheathing............-. 22-0222 - eee eee eee eee 59. C. prasina.
Leaves pubescent; périgynia more than 3 mm. long.............------ 60. C. davisii.

19. Paniceae Tuckerm.
Plant with long slender rootstocks and rather laxly flowered pistillate spikes of
strongly few-nerved perigynia.
A single species............... 02 0c ee cee ec eee eee cee eee ee eee eee 61. C. tetanica.

20. Griseae Bailey.

Distinguished from all other species in our region by the impressed nerves of the
perigynia.
Perigynia tapering at the base, constricted at the apex, obtusely triangular in cross
section.
Sheaths glabrous; perigynia 4.5-5 mm. long.........-.......- 62. C. oligocarpa.
Sheaths pubescent; perigynia 3.5-4 mm. long............ 63. C. hitchcockiana.

106 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Perigynia rounded at both ends, circular in cross section.
Leaves firm, very glaucous; lower scales exceeded by the perigynia.

64. C. glaucodea.

Leaves thin, soit, not glaucous; lower scales at least equaling the perigynia,
Spikes widely scattered; leaves 2-4 mm, wide, erect; perigynia scarcely turgid.
65. C. amphibola.
Spikes borne principally in the upper axils; leaves 4-6 mm. wide, spreading
perigynia turgid.........2..2..2..2-0.-22-2-- vee e cece eee eens 66. C. grisea.

21. Laxiflorae Kunth.

Flowering culms lateral; spikes more or less laxly flowered; perigynia subfusiform,
many-nerved.

Perigynia sharply angled, short-tapering at the base.
Staminate scales dark brown or purplish; perigynia 5-7 mm. long.
67. C. careyana.
Staminate scales straw-colored or pale brown; perigynia 2-4 mm. long.
Basal leaves 1-3 cm. wide; pistillate spikes sessile, erect; perigynia smooth,
68. C. platyphylla.
Basal leaves usually narrower (if 1 cm. wide, the pistillate spikes flexuous on
capillary peduncles); perigynia minutely roughened.
Scales blunt; staminate spikes sessile or nearly so; peduncles short, erect.
69. C. abscondita.
Scales acuminate to aristate; staminate spikes usually strongly peduncled;
lower peduncles capillary.
Perigynia 2.8-3.2 mm. long, short-beaked; leaves usually exceeding the

culm, 2.5-5 mm. wide, erect..................2.0.--00-- 70. C. digitalis.
Perigynia 3.3-4-mm., long, beakless or nearly so; leaves usually exceeded by
the culm, 4-8 mm. wide, spreading.................. 71. C. laxiculiis.

Perigynia obtusely angled, long-tapering at the base.
Leaves 1.5-4 cm. wide; pistillate scales truncate. Culms flattened and wing-mar-
gined . eee eee eee cece ee eee ...72. C. albursina.
Leaves 0.3-2 cm. wide; pistillate scales acuminate to strongly cuspidate.

Spikes short, 5-10-flowered, the lower on capillary, spreading or drooping pedicels.
73. C. styloflexa.

Spikes elongate, 8-20-flowered, the lower normally on stiff erect peduncles.
Perigynia obovoid; beak abruptly bent, minute; sterile shoots developing
conspicuous culins,
Staminate spike usually small and hidden among the pistillate, short-stalked

or sessile; culms stout, winged......................002- 74, C. blanda.
Staminate spike prominent, usually projecting above the pistillate, usually
long-stalked; culms slender, not winged................ 75. C. laxiflora.

Perigynia ellipsoid-fusiform; beak straight or oblique, elongate; sterile shoots
reduced to mere tufts of leaves.

Culms stout, densely cespitose; basal leaves less than 30 cm. long, their
sides not parallel; perigynia appressed-ascending in an alternate-flowered

Spike .. 2.0.2... eee eee eee eee eee eee ....76, C, anceps.
Culms slender, often loosely cespitose; basal leaves usually more than 30 cm.
long; perigynia spreading-ascending, mostly overlapping in the dense
spike.........222.2.....-... cece cece cece cece eee eeeee 77. C. striatula.

22. Granulares Bailey.

‘Perigynia brown, ascending, granular-roughened.

A single species .......... 22.2.2. 02 2c eee cece cece cence eeeeeeees 78. C. granularis.

FLORA OF THE DISTRICT OF COLUMBIA. 107

23. Flavae Tuckerm.
Perigynia yellowish green, the tips spreading or reflexed; spikes short, aggregate.
A single species. ........2..-0. 2.02222 e ce eee eee eee teen eee 79. C. oederi.
24. Hirtae Tuckerm.

Wet land plants with short-hairy or glabrous perigynia, usually with short stout
teeth, these very thin in C. vestita, however.

Perigynia glabrous. .......-.-..- 2-22-2222 e eee eee ee eee eee e eee 80. C. lacustris.
Perigynia densely pubescent.
Beak of perigynium strongly bidentate................-.-.+--+-- 81. C. lanuginosa.
Beak of perigynium not strongly bidentate...............-..----+--- 82. C. vestita.

25. Pseudocyperae Tuckerm.
Perigynia many-nerved, scarcely inflated. Swamp and marsh plants.

Teeth of the perigynium 1.2-2 mm. long; plants stout.............-.- 83. C. comosa.
Teeth of the perigynium less than 1 mm. long; plants somewhat slender.
84. C. hystericina.
26. Physocarpae Drejer.

Late speciés, usually not mature before midsummer; relatively tall.

Body of the perigynium obconic or obovoid, truncately contracted into a prominent
beak.
Perigynia shorter than the rough-awned scales; terminal spike small, usually

staminate.............-.------- 22-2 eee 85. C. frankii.
Perigynia longer than the scales; terminal spike with both staminate and pistillate
flowers.
Spikes oval; scales acuminate or awned.............------+++--- 86. C. squarrosa.
Spikes oblong-cylindric; scales blunt.............---..------ ....87. C. typhina.

Body of the perigynium lanceolate to ovoid, not truncately contracted.

Perigynia lanceolate or lance-subulate, tapering into the beak, many-nerved.
Perigynia yellowish green, the teeth straight...........-------- 88. C. folliculata.
Perigynia bright green, the teeth refracted............-.--+----- 89. C. collinsii.

Perigynia broader, abruptly contracted into the beak, usually strongly ribbed.
Length of perigynia less than 10 mm.

Scales rough-cuspidate; staminate spike solitary......-...----- 90. C. lurida.
Scales obtuse to short-cuspidate, not roughened; staminate spikes 2 or more.
Culms scarcely spongy at the base; leaves scarcely or not at all nodulose;
beak of perigynium usually roughened..............---- 91. C. bullata.
Culms thick and spongy at the base; leaves strongly nodulose; beak of
perigynium smooth...........--- cece eee eee eens 92. C. rostrata.
Length of perigynia 10 mm. or more. Staminate spike solitary. .
Pistillate spikes globose or subglobose; style straight...... 93. C. intumescens.
Pistillate spikes oblong or cylindric; style abruptly bent.
Culms arising singly from an elongate rootstock; leaves 2-5 mm. wide,
94. C. louisianica.
Culms cespitose; leaves 4-10 mm. wide..............------ 95. C. lupulina.

1. Carex retroflexa Muhl.

Thickets and dry woods; fairly common; chiefly in the Piedmont Region; also at
Ammendale. May 10-June 1. Eastern U. 8.
2. Carex convoluta Mackenzie.

Damp or rich woods; common in the Piedmont Region; also along Paint Branch,
and at Ammendale. May-June. Me. to Neb. and Ala. (C. rosea of Ward’s Flora.)

108 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Besides the typical form, plants with much narrower leaves and smaller, somewhat
ascending perigynia are often found.
3. Carex rosea Schkuhr.

Woods and thickets; common, Latter part of May. Eastern U. S. (C. rosea
radiata Boott; C. rosea minor of Ward’s Flora.)

A densely cespitose form with nearly prostrate culms, lax, almost capillary leaves,
and extremely narrow perigynia is often found in damp, shaded places.

4, Carex muricata L.

Collected several times in the Mall. May 15-June1. Me. to Ohio and Va.; locally
naturalized from Eur.

5. Carex muhlenbergii Schkuhr.

Sparse throughout the region. May-June. Eastern U. S.

Nearly all the specimens collected here have the perigynia nerveless or nearly so
(C. muhlenbergit enervis and C. muhlenbergii xalapensis of Ward’s Flora), but a few
have the perigynia more or less strongly nerved.

. 6, Carex mesochorea Mackenzie.

Apparently rare, although specimens have been collected in rather diverse locali-
ties; Ammendale; High Island; Dyke. May 20-June 10. D.C. to Tenn. and Kan.
7. Carex cephalophora Muhl.

Common throughout the Piedmont Region and extending into the Coastal Plain,
at least along the wooded banks of streams. May-July. Eastern U. S®@

8. Carex leavenworthii Dewey.

Seemingly not so common as the preceding species, but occurring throughout the
region in woods or meadows. May 10-June 10. Ont. to D. C., Iowa, and Tex. (C.
cephalophora angustifolia Boott.)

9, Carex aggregata Mackenzie.

Described from specimens collected in the District by Steele; not common. May
15-June 10. D.C. to Mo. (C. divulsa of Holm’s list and C. gravida of Steele’s list,
apparently.)

10. Carex sparganioides Muhl.

Damp woods and thickets; fairly common. May-July. Northern states, south
to Va.

Recognized by the broad, soft, deep green leaves and long interrupted inflorescences,
11. Carex conjuncta Boott.

Collected several times at the upper end of the Potomac Flats, where the Lincoln
Monument now stands. Last of May and first half of June. Northern states, south
to D.C.

Carex alopecoidea Tuckerm., listed by Holm, is not represented by specimens, It
may be distinguished from the C.. conjuncta by its few-nerved, distinctly stipitate
perigynia, —

12. Carex vulpinoidea Michx.

Mostly in wet or swampy places and swales; common. June-Aug. Eastern U. 8S.
(This species, or the next, presumably C. multiflora of Brereton’s Prodromus; (. setacea
of Steele’s list is possibly an extreme form of this.)

The culms are more slender than those of the following species and the leaves more
lax, thus giving the plant a more spreading habit.

13. Carex annectens Bicknell.

Fields; common. June-Aug. Me. to Md. and Mo. (C. xanthocarpa Bicknell; C.
setacea ambigua Fernald.)

Somewhat coarser and stiffer than the last.

14. Carex decomposita Muhl.

Borders of streams and ponds; Great Falls; Broadwater; Dyke. First week in

June. Eastern U.S.

FLORA OF THE DISTRICT OF COLUMBIA. 109

15. Carex stipata Muhl.

Marshes, swamps, and swales; common. May 15-June 15. Nearly throughout the

U.S.

16. Carex laevivaginata (Kiikenth.) Mackenzie.
Marshes, swamps, and swales; common. May 15—-June 15. Mass. to N.C. and II.
Leaves narrower than in the preceding.

17. Carex canescens L.

Swamps and bogs; Coastal Plain. Late May-July. Throughout the northern U.S.

Reported to hybridize freely. Our form has widely separate spikes (C. canescens
disjuncta Fernald.)

18. Carex bromoides Schkuhr.

Swampy woods on Alexanders Island, the only station known here. Latter part
of May. Eastern U.S.

Occasionally dioecious.

19. Carex rosaeoides E. C. Howe.

Swampy woods; not common. May. Mass. to Ga. (C. seorsa E. C. Howe.)
20. Carex cephalantha Bicknell.

Wet woods and swamps. Middle of May to middle of June. Throughout the U. S.
(C. stellulata cephalantha Fernald; C. atlantica of Steele’s list. )
20a. Carex angustior Mackenzie.

In damp woods near Paint Branch Swamp, June 25, 1915 (Standley 11751). North-
ern U.S., south toD.C. (C. stellulata angustata Carey.)

21. Carex incomperta Bicknell.

Moist soil; the commonest species of the group in our region. May-June. Mass. to
Mich. and Fla. (C. stellulata of Ward’s Flora.)

22. Carex interior Bailey.

Edge of pool, Maryland shore opposite Plummers Island; Mount Vernon; also along
the Patuxent. Last of May and first of June. Throughout the U.S. (C. scirpoides of
Gray’s Manual.)

23. Carex howei Mackenzie.

Collected June, 1882, Ward, no locality cited other than District of Columbia. Mass.
to D.C. (C. scirpoides capillacea Fernald; C. interior capillacea Bailey.)
24. Carex scoparia Schkuhr.

Usually in low ground. May-Aug. Nearly throughout the U.S.

25. Carex tribuloides Wahl.

Low moist ground; less common than the preceding. July-Sept. Throughout the
U.S., east of Rocky Mts. (C. lagopodioides Schkuhr.)

26. Carex projecta Mackenzie.

Not common, but found throughout the region. July-Sept. Northeastern U. 8.
(C. tribuloides reducta Bailey; C. tribuloides moniliformis Britton.)

27. Carex cristatella Britton.

Meadows; mostly confined to the Coastal Plain. July-Aug. Northeastern U. 8.
(C. cristata Schwein.)

28. Carex albolutescens Schwein.

Wet soil of the Coastal Plain. May-July. Atlantic and Pacific coasts and Great
Lakes region. (C. foenea of Ward’s Flora.)

29. Carex straminea Willd.

Wet soil. May-July. Eastern U.S. (C. straminea aperta of Ward’s Flora.)
30. Carex festucacea Schkuhr.

Usually in wet soil. May-July. Northeastern U. 8. (C. straminea tenera of
Ward’s Flora.)

31. Carex brevior (Dewey) Mackenzie.

Low open ground. May-July. Eastern U.S. (C. festucacea brevior Fernald.)
32. Carex alata Torr.

Moist soil; Coastal Plain. May-July. Eastern U.S.

110 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

33. Carex hormathodes Fernald.

Specimens approaching the variety richii Fernald have been collected near Great

Falls. May-June. Eastern U. 8.
34. Carex crinita Lam.

Swamps, ditches, and wet places. June-Aug. Eastern U.S.
35. Carex gynandra Schwein.

Along streams, swamps, and wet places; apparently mostly confined to the Coastal
Plain. Late May-Aug. Northeastern U. S. and along the mountains to Ga. (C.
crinita gynandra Schwein. & Torr.)

36. Carex torta Boott.

Along streams throughout; apparently rare and local. May-June. Northeastern U.S.
87. Carex stricta Lam.

Along the Potomac and E stern Branch. May-June. Northeastern U. 8. (C. an-
gustata of Ward’s Flora.)

38. Carex emoryi Dewey.

Shores of the Potomac and its larger tributaries in the Coastal Plain. May-June.
Northeastern and central U.S. (C. stricta angustata of Steele’s list.)

39. Carex aquatilis Wahl.

Shores of the Potomac and Eastern Branch. May-July. Noftheastern U.S. (C.
saxatilis of Brereton’s Prodromus is probably this species.)

C. goodenovit Gay (as C. vulgaris Fries) is reported in Ward’s Flora, but there are
no specimens at hand.

40. Carex leptalea Wahl.

Bogs and swamps throughout, usually in sphagnum. June-Aug. Northern U. 8.

(C. polytrichoides Muhl.)
41. Carex willdenovii Schkuhr.

Usually in dry woods. May-July. Eastern U.S.
42. Carex jamesii Schwein.

Woods; apparently confined to the Piedmont Region. Apr.—July. Northeastern
U.S. (C. steudelti Kunth.)

43. Carex nigromarginata Schwein.

Plummers Island; High Island; Linnean Hill. Apr.-May. Northeastern U. 8.
44. Carex tonsa (Fernald) Bicknell.

Dry hills. May-July. Northeastern U.8. (C. wmbellata tonsa Fernald; C. umbellata
of Ward’s Flora.) ,

45. Carex communis Bailey.

On rocks of Potomac shore above the fall line. May-June. Northeastern U.S. (C.
pedicellata Britton.)

46. Carex emmonsii Dewey.

Common on dry hillsand among rocks. May. Eastern U. 8. (C. varia Muhl., not
Lumnitz.)

47. Carex pennsylvanica Lam.

Common in dry soil. May. Northeastern U.S.

48. Carex hirtifolia Mackenzie. .

Rich woods of the Piedmont Region. May-June. Northeastern U. 8. (C.
pubescens Muhl.)

49. Carex pallescens L.

Woods; Anacostia and near St. Elizabeths. May-Aug. Northeastern U. S.
(Including C. pallescens undulata A. Gray.)

50. Carex shortiana Dewey.

Meadows and low woods. May-July. Northeastern U. 8S., south to D.C.
51. Carex swanii (Fernald) Mackenzie.

Dry woods; apparently confined to the Coastal Plain. Middle of May to middle of
June. Northeastern U. 8. (C. virescens swanti Fernald; C. virescens elliptica of
Ward’s Flora.)

FLORA OF THE DISTRICT OF COLUMBIA. lll

52. Carex virescens Muhl.

Damp woods of the Piedmont Region. May-July. Eastern U. 8S. (C. costellata
Britton.)
53. Carex caroliniana Schwein.

Meadows; mostly in the Coastal Plain. May-June. Southeastern U. S., north
to N. J. (C. triceps smithii Porter.)

54. Carex complanata Torr.

Woods and meadows. May-June. Eastern U. 8S. (C. triceps Michx.; C. triceps
hirsuta Bailey.)
65. Carex bushii Mackenzie.

Thickets and fields throughout; not common. May-—July. R. I. to S. ©. and
Okla. (C. triceps cuspidata Dewey.)

The bristly, usually stiffly erect spikes distinguish this species from its allies.
56. Carex debilis Michx.

Swampy places; mostly in the Coastal Plain. June. Southeastern U. 8.

Carex debilis pubera A. Gray was collected by Steele in a “swampy place, 1 mile
east of Kenilworth, May 14, 1898.”
57. Carex oblita Steud.

Swamps and bogs of the Coastal Plain. May-June. Eastern U. 8. (C. venusta
minor Boeck.)
58. Carex gracillima Schwein.

Woods; mostly if not entirely confined to the Piedmont Region. May-June.
Northeastern U. 8.
59. Carex prasina Wahl.

Rich or wet woods; mostly above the fall line. May. Northeastern U.S. (C.
miliacea Muhl.)
60. Carex davisii Schwein. & Torr.

Collected but once, ‘‘among rocks at Great Falls, Md., June 2, 1905, Theodor
Holm.’ Mississippi Valley; infrequent eastward.
’ 61. Carex tetanica Schkuhr.

Woods; throughout. May-June. Northeastern U. 8., south to D.C. (Including
C. tetanica woodit of Ward’s Flora.)
62. Carex oligocarpa Schkuhr.

Woods; Plummers Island; Glen Echo; Seven Locks. May-June. Northeastern
U.S.
63. Carex hitchcockiana Dewey.

Rich woods; above the fall line. May-June. Northeastern U. 8S.
64, Carex glaucodea Tuckerm.

Apparently confined to the Coastal Plain. May-June. Northeastern U. 8.
65. Carex amphibola Steud.

Dry soil. May-June. Eastern U.S. (C. grisea angustifolia Boott.)
66. Carex grisea Wahl.

Rich woods. May-June. Eastern U.S8., south to N. C.
67. Carex careyana Torr.

Woods; Seven Locks; near Langley; rare. May. N. Y. to Mich. and D. C.
68. Carex platyphylla Carey.

Woods; apparently confined to the Piedmont Region. May. Me. to Ill. and Va.
69. Carex abscondita Mackenzie.

Moist woods; Beltsville; Riverdale. May-June. Eastern U. 8. (C. ptychocarpa
Steud.)
70. Carex digitalis Willd.

Woods and thickets; essentially a plant of the Piedmont Region, though specimens
have been collected at Dyke. May-June. Eastern U. S.

112 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

71. Carex laxiculmis Schwein.

Wooded slopes of the Piedmont Region. May-June. Me. to Mo. and Va. (C.
retrocurva Dewey.)

72, Carex albursina Sheldon.

Woods; Plummers Island and High Island. May. Northeastern U. 8. (C.
laxiflora latifolia Boott.)

73. Carex styloflexa Buckl.

Wet woods; Eastern Branch; Bennings; Beltsville. May. Eastern U. 8, (C.
laxiflora styloflexa Boott.)
74, Carex blanda Dewey.

Woods and meadows. May. Northeastern U. 8. (C. laxiflora blanda Boott; C.
laxiflora varians Bailey.)

75. Carex laxiflora Lam.

Woods and meadows. May. Eastern U. 8S. (Including C. laxiflora gracillima
Boott and C. laxiflora intermedia Bailey.)

76. Carex anceps Muhl.

Woods and meadows; apparently common. May. Eastern U. S., south to N.C,
(C. laxiflora patulifolia Carey; C. laxiflora plantaginea of Ward’s Flora.)

77. Carex striatula Michx.

Woods and meadows. May. Southeastern U. S., north to N. J. (C. lazvylora
divaricata Bailey.)

78. Carex granularis Muhl.

Moist woods. May-June. Eastern U.S.
79. Carex oederi Retz.

But once collected, ‘‘Washington, D. C., Aug. 9, 1879, Ward;” the one rather poor
specimen seems to be near the var. pumila Fernald. Northern U.S. (Possibly C.
flava of Brereton’s Prodromus. )

80. Carex lacustris Willd.

Swamps and marshes of the Coastal Plain. May-July. Northeastern U. S., south
to D.C. (C. riparia of Ward’s Flora.)
81. Carex lanuginosa Michx.

Swampy places along the Potomac. May-June. Northern states, south to D. C.
82. Carex vestita Willd.

Sandy soil, throughout; not common. May-June. Northern states, south to Ga.
83. Carex comosa Boott.

Swamps and edges of pools. June-July. Nearly throughout the U.S. (C. pseudo-
cyperus of Ward’s Flora.)

84. Carex hystericina Muhl.

Swales and wet places; First Lock; flats below Chain Bridge. May-June. Widely
distributed in the U.S.

85. Carex frankii Kunth.

Wet ground; Piedmont Region. June-Aug. Southern states, north to Pa. (C.
stenolepis Torr.)

86. Carex squarrosa L.

Swampy places throughout the region. May-Aug. Eastern U. 8.
87. Carex typhina Michx.

Lakeland, Aug. 4, 1900 and June 5, 1902 (Steele). Eastern U.S. (C. typhinoides
Schwein.)

88. Carex folliculata L.

Rather frequent in boggy places, especially in the Coastal Plain. June-Aug.
Northern states, south to N.C.

89. Carex collinsii Nutt.

Collected but once, in a small bog near Suitland, July 4, 1917. R.I.to Ga. (C.
subulata Michx.)

FLORA OF THE DISTRICT OF COLUMBIA. 1138

90. Carex lurida Wahl.

Wet places, everywhere. Summer. Eastern U.S. (C. tentaculata Muhl.; includ-
ing C. lurida exundans Bailey.)

Exceedingly variable; spikes subglobose to cylindric, sessile to long-pedunculate.
91. Carex bullata Schkuhr.

Swamps; Hyattsville. May-June. Me. to Ga.
92. Carex rostrata Stokes.

Bennings Bridge, June 8, 1879 (Ward). Nearly throughout the U .S. (C. utriculata
Boott; C. vesicaria of Brereton’s Prodromus, probably.)
98. Carex intumescens Rudge.

Low or wet woods of the Coastal Plain. May-Sept. Eastern U. 8.
94. Carex louisianica Bailey.

Swamps along the Potomac and Eastern Branch. July-Aug. Southeastern U. S.,
north to D. C.
95. Carex lupulina Muhl.

Swamps. July-Aug. Eastern U.S.

C. lupulina pedunculata Dewey, with more or less pedunculate spikes, occurs
sparingly.

Carex buxbaumiit Wahl. (C. fusca of Steele’s list) has been reported, but there are
no specimens in the National Herbarium.

18, ARACEAE, Arum Family.

Leaves compound, composed of 3 or more leaflets. Flowers in a dense spike, this
surrounded by aspathe.............--------- wee cece eee eeeeee 1. ARISAEMA.
Leaves simple.
Leaves linear, less than 1.5 cm. wide; flower spike naked, borne on a long, sharply
3-angled stalk, the stalk prolonged above the spike............--- 2. ACORUS.
Leaves broader than linear, usually more than 5 cm. wide; flower stalk not pro-
longed above the spike.
Leaves tapering at the base; flower spike naked.........-.-.-.-- 3. ORONTIUM.
Leaves not tapering at the base, usually somewhat heart-shaped or arrow-
shaped; flower spikes surrounded by a spathe.
Leaves ovate or oval, usually more or less heart-shaped; flower stalks very

short and stout; sepals 4...............-2--------+---- 4, SPATHYEMA.
Leaves usually arrow-shaped and with long acute lobes at the base; flower
stalks usually long and slender; sepals none....-..--.-. 5. PELTANDBA.

1. ARISAEMA Mart.

Leaves composed of 5-17 leaflets; spathe surrounding the flower spike erect, not

hooded... 2... cee ee ee eee eee eee eee eeeeees 1. A. dracontium.

Leaves composed of 3 leaflets; spathe hooded (curved down over the flower spike).

- 2. A. triphyllum.

1. Arisaema dracontium (L.) Schott. GREEN DRAGON,
Low rich woods; occasional. May-June; fr. Aug.-Sept. Eastern U. 8S.

2. Arisaema triphyllum (L.) Torr. JACK-IN-THE-PULPIT.

Moist woods and thickets; common, Apr.June. Eastern N. Amer.

The species is a very variable one. The spathes are usually more or less colored or
striped with brownish purple, but sometimes they are wholly green. Very often
plants are wholly staminate or wholly pistillate. A. triphyllum pusillum Peck is a
small form with the spadix 3-5 cm. long; in the larger plants the spadix is usually
5-7 cm. long. This form has been recognized asa species, A. pusillum (Peck) Nash,
but hardly seems worthy of special designation.

69289—19—_8

114 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

The bulbs and bright red berries are intensely acrid. They contain needle-like
crystals of calcium oxalate which readily penetrate the tongue when a piece is chewed,
causing swelling, as do the leaves of the common caladium or elephant’s-ear (Colocasia
antiquorum esculenta), which also is a member of this family. Another name for the
species is Indian turnip.

2. ACORUS L.
1. Acorus calamus L. SWEET FLAG.

Marshes and along streams; common along the lower Potomac. May-June. Eastern
N. Amer.; also in Eur. and Asia.

Known also as calamus or flag-root. The thick rootstocks, as well as the leaves,
have a pleasant flavor; they are used in medicine.

3. ORONTIUM L.
1. Orontium aquaticum L. GOLDEN CLUB.
In or at the edge of water; common and often very abundant. Apr.-May. Eastern
U.S.
4. SPATHYEMA Raf.

1. Spathyema foetida (L.) Raf. SKUNK CABBAGE.
Swamps and wet woods; common. Feb.~Apr. Eastern N. Amer. (Symplocarpus
Joetidus Nutt.)
All parts of the plant have a strong, disagreeable odor which suggests the common
name. The flowers appear very early in the spring, usually before the leaves. A
group of plants in leaf as they appear in May in shown in plate 14.

5. PELTANDRA Raf.

1. Peltandra virginica (L.) Kunth. - ARROW ARUM.

Swamps or shallow water; often very abundant. May-June. Eastern U. 8S.

The leaves vary greatly in shape. In the typical form, which is the most common,
they are broadly halberd-shaped or arrow-shaped, with long acute lobes at the base.
In P. virginica heterophylla (Raf.) Tidestrom the leaves are very narrow and either
rounded at the base or with short rounded lobes. In P. virginica angustifolia (Raf.)
Tidestrom the leaves are still narrower, 4 cm. wide or less, and usually rounded at the
base. A detailed account of these forms has been published by Tidestrom.'

19. LEMNACEAE. Duckweed Family.

Plants without roots; plant body distinctly rounded above, minute, without nerves,
1. WOLFFIA,
Plants with roots; plant body distinctly flattened above, with one or more nerves.

Plant body 1-3-nerved, normally green throughout, bearing only one root.

2. LEMNA.

Plant body 5-15-nerved, normally purple beneath, bearing several roots.

3. SPIRODELA.
1. WOLFFIA Horkel.
1. Wolffia columbiana Karst.

Floating on the surface of spring-fed ponds on the Maryland shore of the Potomac
near Plummers Island; also in pools along the canal, near the District line. East-
ern U.S.

The smallest flowering plant of our region; not known to bloom locally.

2. LEMNA L. Duckweep.
1. Lemna perpusilla Torr.
Common on the surface of stagnant or slow-moving water. Blooms freely in mid-
summer, setting seed rather abundantly. Eastern U. 8. (Probably L. minor of
Ward’s Flora.)

’ Rhodora 12: 45-50. pl. 83. 1910.

FLORA OF THE DISTRICT OF COLUMBIA. 115

3. SPIRODELA Schleid.

1. Spirodela polyrhiza (L.) Schleid.

Common on the surface of stagnant or slow-moving water, usually associated with
Lemna. Blooms in midsummer, but rarely sets seed, and goes through the winter in
a condeused resting stage in the mud on bottoms of ponds. Generally distributed
in temperate and tropical regions. (Lemna polyrhiza L.)

20. XYRIDACEAE. Yellow-eyed grass Family.

1. XYRIS L. YELLOW-EYED GRASS.

Bracts of the head with a definitely marked green middle part; lateral sepals mi-
nutely erose on the keel; stems subcompressed and narrowly 2-winged toward
the summit, slender, scarcely flexuous; leaves mostly flat, grasslike.

1. X. caroliniana.

Bracts of the head usually green-tipped but with no marked line between the middle
and the margins; lateral sepals ciliolate on the keel, a tuft of silky hairs at the
apex; stems not compressed, obscurely 3-angled toward the summit, usually wiry
and flexuous; leaves usually firm and flexuous. ..........------- 2. X. flexuosa.

1. Xyris caroliniana Walt.

Among sphagnum in white sand of magnolia bogs; Powder Mill Swamp region and
near Savage Station. Aug.—Sept. Atlantic Coastal Plain and at the head of Lake
Michigan.

2, Xyris flexuosa Muhl.

Wet sandy sunny places in bogs and along streams and ditches; Takoma Park,

southward and eastward, and at Arlington; infrequent. July-Aug. Eastern U.S.

21. ERIOCAULACEAE. Pipewort Family.

1. ERIOCAULON L. Prrewort.

Scapes weak, not rigid, not over 15 cm. tall unless submerged. Sheaths loose; leaves
scarcely longer than the sheaths...........-.-.------------ 1. E. septangulare.
Scapes firm, strongly 10-14-ridged, commonly 50 cm. tall, more or less twisted.

2. E. decangulare.
1. Eriocaulon septangulare With.

Alluvial soil by streams and tidal flats; near the mouth of the Eastern Branch and
at the mouth of Fourmile Run. Aug.-Sept. Eastern U. S.

2, Eriocaulon decangulare L.

Among sphagnum, mostly in magnolia bogs; Takoma Park, southward and eastward.
Aug.-Sept. Atlantic Coastal Plain from N. J. southward.

The seeds of Eriocaulon are dispersed by the wind. At maturity in late September
and October the chaffy floral bract and the fertile flower with its dry sepals and
corolla and ripened capsule break away from the receptacle as a whole and float
in the breeze, buoyed up by the tufts of copious hairs.

22, COMMELINACEAE. Spiderwort Family.

Most of the plants of this family are somewhat succulent, and have mucilaginous juice
and frequent cells with needle-shaped crystals. Several species of different genera
are cultivated as house plants, the most common being one of: the Wandering Jews
(Zebrina pendula Schnizl.), with leaves purple beneath.

Petals equal, purplish blue; filaments bearded; perfect stamens 6; bracts leaflike or
inconspicuous; leaves long-linear. Flowers in terminal umbels.
1. TRADESCANTIA.

116 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Petals unequal, blue or white; filaments naked; perfect stamens 3; bracts heart-shaped,
folded, forming a spathe with the margins often partly united; leaves short, ovate
to lanceolate... 2.2.0.6... cece ccc cece cece eee ee ceeeees 2. COMMELINA.

1, TRADESCANTIA L. SpipERworrt.

The commoner green-leafed Wandering Jew in cultivation is 7. fluminensis Vell., of
South America.

1. Tradescantia virginiana L.

Rich woodlands along the Potomac above Washington; common. May-Aug. Conn.
to 8. C.

The flowers open at night and the petals collapse by midday. A plant in bloom is
shown in plate 15A.

2. COMMELINA L. Day FLoweEr.

Spathe margins free. Capsule 2-celled, 4-seeded; flowers with 2 blue petals and one
smaller white one; seeds rugose; glabrous or somewhat hairy annuals; spathes few,
axillary, peduncled.................. cece cece eee cece eee ees 1, C, communis,

Spathe margins united at the base.

Capsule with 3 cells, each 1-seeded, or one cell reduced; leaf sheaths and spathes
glabrous or with white hairs; plant low, perennial, with a cluster of somewhat
fleshy roots; spathes single or few together, peduncled; petals 2, blue.

2. C. erecta.

Capsule with 2 2-seeded cells, the other cell with a single larger seed; leaf sheaths
ciliate with stout brown hairs; plant 60-150 cm. high, perennial by horizontal
rootstocks; spathes terminal, clustered, sessile; petals 3, blue. .3. C. virginica.

1. Commelina communis L. Witp WanpeERING JEW.

A common and persistent weed in gardens and moist soil. July-Oct. N. Y. to Ga.;
introduced from eastern Asia.

The stems retain vitality for days after being cut and root readily. The flowers
are notable for the contrast of the blue petals and yellow stamens.
2. Commelina erecta L.

Along rocky streams, often in dry situations; not common; High Island; Fourmile
Run; Great Falls. June-Sept. N. Y.to Tex. (C. virginica of Ward’s Flora.)
3. Commelina virginica L.

Frequent along margins of the Eastern Branch and Potomac. Aug.-Oct. Eastern
U.S. (C. erecta of Ward’s Flora; C. hirtella Vahl.)

23. PONTEDERIACEAE, Pickerel-weed Family.

Plants erect, 30-120 cm, tall; leaves large, arrow-shaped; flowers in spikes, bright blue.
1. PONTEDERIA.

Plants creeping or submerged; leaves linear or reniform; flower8 in few-flowered
spathes, blue, white, or yellow......................... 2. HETERANTHERA.

1. PONTEDERIA L.
1, Pon tederia cordata L. PICKEREL-WEED,
Abundant in marshes. June-Aug. Eastern U. 8.
Plate 16 shows a colony in flower in a marsh near Dyke,

2. HETERANTHERA Ruiz & Pav.

Leaves reniform; plants creeping on mud; flowers white or pale blue.
1. H. reniformis.
Leaves linear, grasslike; plants submerged; flowers yellow..............2. H. dubia.

FLORA OF THE DISTRICT OF COLUMBIA. 117

1. Heteranthera reniformis Ruiz & Pav. MuD PLANTAIN.
Tide flats and other muddy places or in shallow water; along the canal, Carberry
Meadows; Eastern Branch; Hunting Creek. Aug. Eastern U.S. W. Ind., 8. Amer.

2. Heteranthera dubia (Jacq.) MacM. WATER STAR-GRASS,
Quiet shallow water; in the canal, pools along the Potomac, and creek mouths.
July-Sept. U.S., Cuba, Mex. (Schollera graminea A. Gray.)

24, JUNCACEAE. Rush Family.

Capsule many-seeded, 1-3-celled; placente parietal or axial; leaf sheaths open.
1. JUNCUS.
Capsule 3-seeded, 1-celled; placente basal; leaf sheaths closed..... 2. JUNCOIDES.

1. JUNCUS L. Rusu.

Juncus repens Michx. has been found at Salisbury, Maryland, and may occur within
our limits. It would come in the key next to J. marginatus, from which it is distin-
guished by its long perianth (6-10 mm. long) and its floating or ascending stems.

Leaves reduced to bladeless mucronate basal sheaths; leaf of the inflorescence seem-
ingly continuous with the stem, the inflorescence therefore appearing lateral.
Stems tall, erect, naked..........2.--2...-.-.---2-----55 cee eeeee 1. J. effusus.

Leaves with well- developed grasslike blades; inflorescence clearly terminal.

Leaves hollow, with cross partitions, appearing jointed when dry, usually terete.
Seeds with a distinct whitish appendage (‘“‘tail’’) at each end.
Seeds loosely covered by the seed coat, the latter prolonged into tails about as
long as the body of the seed; inflorescence stiff.......... 12. J. canadensis.
Seeds tightly covered by the seed coat, the latter honeycombed and prolonged
into tails only about one-third as long as the seed body; inflorescence loose.

13. J. subcaudatus.
Seeds not tailed, usually with short abrupt dark tips.

Capsule prismatic, short-pointed....................-.--- 14. J. acuminatus.
Capsule subulate, with long tapering apex.

Perianth 4-5 mm. long, the flower heads (exclusive of the beaks of the cap-
sules) 12-15 mm. in diameter; stamens 6; rootstocks slender, 1-2 mm. in
diameter, bearing small tubers at intervals of a few centimeters.

10. J. torreyi.

Perianth 2.5-3 mm. long, the flower heads (exclusive of the beaks of the cap-
sules) 7-10 mm. in diameter; stamens 3; rootstocks stout, uniform,
2-3 mm. in diameter, even when young..............- 11. J. scirpoides.

Leaves neither jointed nor with cross partitions, either channeled on the upper sur-
face or flattened. -
Flowers crowded in 2-10-flowered heads, not prophyllate (see below).
Heads rather few, mostly 5-10-flowered; stamens shorter than the petals, not

conspicuous in fruit...........-..2.2-...22022222-5--- 8. J. marginatus.
Heads very numerous, usually 2—5-flowered; stamens equaling or surpassing the
petals, persistent and conspicuous in fruit.............-. 9. J. aristulatus.

Flowers solitary along the branches of the inflorescence, prophyllate (that is,
each subtended by two bracteoles in addition to the bractlets at base of

pedicel).
Plants annual; inflorescence, exclusive of its leaves, more than one-third the
height of plant.............--....2.020- 202 cece eee eee .....2 J, bufonius,

Plants perennial; inflorescence, exclusive of its leaves, less than one-third the

height of plant.
Sepals obtuse, green and dark brown, shorter than or barely equaling the
dark brown capsule; stem usually bearing one or two leaves. .3. J. gerardi.

118 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Sepals very acute, pale green or straw-colored, equaling or exceeding the pale
capsule; leaves all basal or essentially so.

Leaves subterete, merely channeled above; basal sheaths usually purplish-
tinged; flowers 3.5-5 mm. long, in 1-sided racemes; leaf sheaths with
short cartilaginous auricles (the narrow borders at the apex of the
sheaths).......2. 220.22 c cece e eee ee ee cece eee ee eeee 7. J. dichotomus.

Leaves flattened, but sometimes inrolled in drying so as to appear involute;
basal sheaths brownish or straw-colored.

Auricles of the leaf sheaths cartilaginous, yellowish when dry.
4. J. dudleyi.
Auricles of the leaf sheaths membranaceous or submembranaceous,
whitish or brownish.

Auricles thin, scarious, whitish, 1-3 mm. long; flowers 3.5-5 mm.
long, loosely scattered or clustered; inflorescence shorter than its
lowest bract............00.. 22220 e eee eee eee ee 5. J. tenuis.

Auricles firmer, brownish, less than 1 mm. long; flowers 2.5-3.5 mm.
long, arranged in 1-sided racemes; inflorescence usually longer than
its lowest bract............ 02.00.00 e eee 6. J. secundus.

1. Juncus effusus L. COMMON RUSH.
Meadows and wet places; rathercommon. June-Aug. N. Amer. and Eur.
The form occurring with us is J. effusus solutus Fern. & Wieg.

2. Juncus bufonius L. TOAD RUSH.
Dried-up pools and wet places; common. May-July. Cosmopolitan.
3. Juncus gerardi Loisel. BLACK GRASS.

Known only from streets of Alexandria,where first collected by Vasey. July. Nearly
cosmopolitan.

Abundant, outside our limits, in the salt marshes of Chesapeake Bay.

4. Juncus dudleyi Wiegand.

Sandy bogs and damp sands; scarce; flats of the Potomac, southwest of Washington
Monument (Coville); High Island and First Lock (Ward). May-June. Greater part of
N. Amer.

5. Juncus tenuis Willd. PATH RUSH.

Abundant throughout in sandy soil; a characteristic plant along paths. June-
Aug. N. Amer.; introd, and spreading in the Old World.

6. Juncus secundus Beauv.

Fairly common in sandy abandoned fields. June. Eastern N. Amer. (J. tenwis
secundus Engelm.)

7. Juncus dichotomus Ell.

Low sandy ground and meadows; frequent, especially toward salt water. June-
Sept. Eastern N. Amer.; trop. Amer.

8. Juncus marginatus Rostk.

Meadows and wet grounds; abundant. June-Sept. Eastern N.-Amer. (Includes
J. marginatus vulgaris of Ward’s Flora.)

9. Juncus aristulatus Michx.

Frequent in grassy places. June-July. Eastern N. Amer., south to Mex. (J.
marginatus biflorus of Ward’s Flora; J. marginatus aristulatus Coville.)
10. Juncus torreyi Coville.

Damp sandy ground; scarce; vicinity of Washington (Ward); reservoir, Howard
University, and Jackson City (Steele). July-Aug. Eastern N. Amer. (J. nodosus
megacephalus Engelm.)

11. Juncus scirpoides Lam,

Wet sandy soil; common. July-Aug. Eastern N. Amer. (J. scirpoides macroste-

mon Engelm.)

FLORA OF THE DISTRICT OF COLUMBIA. 119
1
2. Juncus canadensis J. Gay.
Meadows and wet grounds; frequent. Aug—Oct. Eastern N. Amer.; S, Amer.
(J. canadensis longicaudatus Engelm. )
13. Juncus subcaudatus (Engelm.) Coville & Blake.
Wet grounds; rather uncommon. July-Sept. Eastern.N. Amer. (J. canadensis
subcaudatus Engelm.)
14. Juncus acuminatus Michx.
Abundant in wet places. June-Sept. Eastern N. Amer.; Northwest Coast; Mex.

(J. acuminatus legitimus Engelm.)
2. JUNCOIDES Adans. Woop-rus#.

Perianth about equaling the capsule, 2-3 mm. long; base of plant bulblet-bearing;

rays of the inflorescence mostly ascending.......----- 1. J. campestre bulbosum.
Perianth much exceeding the capsule, 2.8-4 mm. long; base of plant not bulblet-
bearing; some of the rays strongly divergent......... 2. J. campestre echinatum.

1. Juncoides campestre bulbosum (A. Wood) Coville & Blake. BuLBous woop-RusH.
Apparently not as common in the District as the next. Apr.-May. Eastern N.
Amer. (Luzula campestris of Ward’s Flora, in part; J. bulbosum Small.)
2, Juncoides campestre echinatum (Small) Coville & Blake.
Apparently the common form of the District. Apr.—May. Eastern N. Amer.
(J. echinatum Small.)
Much more collecting is required before the relative abundance of our two forms
can be established. Material should be collected only in fairly ripe fruit.

25. MELANTHIACEAE. Bunch-flower family.

Flowers solitary, terminal or opposite the leaves; basal leaves undeveloped ; capsule
breaking midway between the septa; perianth lobes more than 1 cm. long.
7. UVULARIA.
Flowers numerous, in a terminal inflorescence; plants with well-developed basal
leaves; capsule opening at the septa; perianth lobes 1 cm. long or less.
Flowers in racemes.
Plants without bulbs; anthers oblong, 2-celled.
Flowers perfect, in loose racemes, each flower with 3 bractlets; leaves linear.
1. TOFIELDIA.
Flowers dioecious, in spikelike racemes, not bracted; leaves oblanceolate.
2. CHAMAELIRIUM.
Plants with bulbs; anthers confluently one-celled. Flowers perfect, bracted.
3. CHROSPERMA.
Flowersin panicles. Antherscordate,one-celled ; inflorescence polygamo-monoecious.
Plants glabrous, from a bulb; sepals lanceolate, broadest at the base.
4. STENANTHIUM.
Plants with pubescent stems, from a rootstock; sepals narrowed at the base.
Perianth segments clawed; leaves long and narrow ..6. MELANTHIUM.
Perianth segments nearly sessile; leaves broadly oval....-...-- 6. VERATRUM.

1. TOFIELDIA Huds.

1. Tofieldia racemosa (Walt.) B.S. P. FALSE BOG ASPHODEL.
Open swampy ground; region beyond Beltsville and Suitland; rare. July. South-
ern N. J. to Fla. (7. pubens Michx.)

2. CHAMAELIRIUM Willd.

1. Chamaelirium luteum (L.) A. Gray. BLAZING STAR. DEvIL’s-BIT.
Moist hillsides in open woods; Rock Creek and upper Potomac regions; once found
near the Reform School. May. Eastern U. 8. (C. carolinianum Willd.)
The characteristic spatulate-leaved evergreen rosettes of this plant are conspicuous
n winter.

120 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

3. CHROSPERMA Raf.

1. Chrosperma muscaetoxicum (Walt.) Kuntze. FLY Porson.
Rare, in dry or damp open woodland; Ammendale and Suitland. June. Southern
states, north to Long. Isl. (Amianthiwm muscaetozicum A. Gray.)

4. STENANTHIUM Kunth.

1. Stenanthium gramineum (Ker) Morong.
Local in swamps near Bladensburg, Terra Cotta, and Fourmile Run. July.
Southern states, north to Pa. (S. robustwm of Ward’s Flora.)

5. MELANTHIUM L. Buncu-FrLowenr.

Blade of perianth segments oblong; leaves linear................ 1. M. virginicum.
Blade of perianth segments orbicular; leaves oblanceolate.......... 2. M. latifolium.

1. Melanthium virginicum L.
Locally abundant in open swampy ground; Reform School, Falls Church, and
other swampy regions. July. Eastern U.S.
2. Melanthium latifolium Desyv.
Dry woods and hills; rare; open ground at Fort Myer; Pinehurst; Stubblefield.
July. Conn. to S.C.
6. VERATRUM L.

1. Veratrum viride Ait. FALSE HELLEBORE.
Rare in swamps and bogs; Laurel; Hollywood Swamp; Lincolnia; Magnolia Run;
Suitland. May. Northern states, south to Ga.

7. UVULARIA L. Betiwortr.

Leaves sessile; capsule acute at both ends.................... ...-1. U. sessilifolia.
Leaves with bases united around the stem; capsule truncate at apex,
2. U. perfoliata.

1. Uvularia sessilifolia L.

Common in woodlands; mostly below the fall line. Apr.-May. Northern states,
south to Ga. (Oakesia sessilifolia S. Wats.)

The flowers are shown in plate 19A.
2. Uvularia perfoliata L.

Common in rich woodland; upper Potomac and Rock Creek regions; Marlboro.
Early May. Eastern U. 8.

26. LILIACEAE. Lily Family.

Among the cultivated genera of this family not included in this list may be men-
tioned: Tulipa, tulips; Scilla, squills; Hyacinthus, common hyacinths; Yucca, yucca,
Hardy forms of some of the above genera are likely to be reported as escapes, but
none seems to be definitely established.

Plants with bulbs or corms. Ovary superior.
Flowers small, in umbels; plants with an onion-like or garlic-like odor. Perianth

6-parted; ovules 1 or 2in a cell........0.0 000022. 1. ALLIUM.
Flowers not in umbels; plants not with an onion odor.

Plants tall, with a leafy stem and terminal inflorescence of large flowers; bulb
of numerous fleshy scales............2.20 20000 e cece cceceeeeee 2. LILIUM.
Plants low, with basal leaves and naked scape; bulb onion-like in structure.
Flowers less than 4 cm. long.
Flowers solitary, bractless; leaves two, broad............. 3. ERYTHRONIUM.
Flowers several; leaves several, narrow.
Perianth of separate spreading segments; flowers green and white, bracted.
4. ORNITHOGALUM.
Perianth segments united, urn-shaped; flowers blue or white. 5. MUSCARI.

FLORA OF THE DISTRICT OF COLUMBIA. - "491

Plants without bulbs or corms. Perianth segments partly united; roots fibrous or
fleshy; plants with basal leaves. .
Ovary superior; flowers large, orange, clustered at the top of a leafless scape.
6. HEMEROCALLIS.
Ovary partly inferior; flowers small, whitish, borne in bracted racemes.

7. ALETRIS.
1. ALLIUM L.

Allium cepa L., common onion, A. sativum L., European garlic, and A. porrum L.,
leek, are grown commonly and all persist more or less after cultivation.

Leaves oblong-lanceolate, absent at flowering time.........-------.-- 1. A. tricoccum.
Leaves linear, present at flowering time.

Inflorescence erect, usually with bulblets; bulb coats more or less fibrous; bulbs

not attached to a rootstock.

Leaves cylindric, hollow, extending half way up the scape; bract enveloping

the umbel splitting down on one side only; bulb coat a thick fibrous

7 0c) 6 OS eeeee 2. A. vineale.

Leaves flat, not extending up the stem much above ground; bract inclosing the

umbel splitting into 3 parts; bulb coat fibrous-reticulate...3. A. canadense,

Inflorescence nodding, without bulblets; bulb coats membranous; bulbs attached

in clusters to a short rootstock. Leaves flat.......----------+-- 4, A. cernuum.

1. Allium tricoccum Ait. WILD LEEK.
Along the Potomac above High Island; rare. Northeastern U.S., south to N.C.
The leaves of this interesting species appear in spring but wither before the flowers

appear in July.

2. Allium vineale L. WILD GARLIC.
Generally distributed as a weed throughout the region. Northeastern U. S., south

to Va.; naturalized from Eur.

The leaves remain green through the winter.

3. Allium canadense L. . MEADOW GARLIC.
Frequent in rich woodlands. June. Eastern U. 8. .
This species can be distinguished by its solitary bulb with netlike fiber coat. The

leaves are not evergreen.

4, Allium cernuum Roth. WILD ONION.
Common in rock crevices and rich soil along the Potomac from Chain Bridge upward.

July. Throughout the U. 8. ,

Leaves evergreen.
2. LILIUM L. Lity.

Many species of Lilium are in cultivation as ornamentals. The tiger lily (L. tigri-
num L.) spreads from gardens and often persists along fences.

Flowers erect; sepals long-clawed, red, scarcely recurved -....- 1. L. philadelphicum.
Flowers nodding or spreading; sepals not clawed, orange or yellow, recurved.

Leaves smooth; sepals strongly recurved, purple-spotted...........2. L. superbum.

Leaves roughened on margins and on veins beneath; sepals moderately recurved,

brown-spotted .......------ 2s eee eee eee ee tener tere ceeeee 8. L. canadense.

1. Lilium philadelphicum L. Woop LILY.

Rare in dry woodlands; Potomac region above the fall line. July. Northeastern
U. S., south to N. C.
2. Lilium superbum L. TURK’S-CAP LILY.
Common in meadows and marshlands northeast of Washington. July. North-
eastern U.8., south to N. C.
3. Lilium canadense L. CANADA LILY.
Rare in wet soil; Bethesda to Terra Cotta. July. Eastern U. 8.

122 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

3. ERYTHRONIUM L. Trout tity.

The plants of this genus are often called adder’s-tongue, or dog-tooth violet.

Flowers yellow; stigmas short, clublike..................--..----- 1. E. americanum.
Flowers white; stigmas 2-3 mm. long, recurved..............--.-.--- 2. E. albidum.
1. Erythronium americanum Ker. TROUT LILY.

Common in moist woodlands. Apr. Eastern U.S.

Sometimes the flowers are deeply tinged with brownish red. The flowers are shown
in plate 17B.
2. Erythronium albidum Nutt. WHITE TROUT LILY.

Locally common in moist woodlands along the Potomac above Little Falls. Apr.
A plant of the Mississippi Valley, extending east in the Potomac Basin to Washington,
alsoin N. Y. and Ga.

4. ORNITHOGALUM L. Star or BETHLEHEM.

Flowers in corymbs, erect; pedicels long, slender................ 1. O. umbellatum.
Flowers in racemes, drooping; pedicels short, stout...................-. 2. O. nutans.

1, Ornithogalum umbellatum L.
Locally common in fields and waste places. May. Northeastern U. 8., south to Va.
Introduced from Eur.
2. Ornithogalum nutans L.
Rare in waste places. Apr. Eastern U.S. Escaped from gardens; native of Eur.
Both species are reported as weeds in Maryland.

5. MUSCARI Mill. Grape HYACINTH.

Perianth oblong, urn-shaped, 4-6 mm. long; leaves narrow, 2-4 mm. wide, recurved.
1. M. racemosum.
Perianth globose, 2-3 mm. long; leaves broader, 4-8 mm. wide, erect.
2. M. botryoides.
1. Muscari racemosum (L.) Mill.
Frequent northwest of Washington in rich soil as a garden escape; well established
along the Potomac. Apr. Northeastern U. S.; native of southern Eur.
2. Muscari botryoides (L.) Mill.
Two collections from Plummers Island. Naturalized from Eur. in the eastern U. S.
This species may be more plentiful around Washington, as IM. racemosuwm has been
confused with it and few collections made of either.

6. HEMEROCALLIS L.
1, Hemerocallis fulva L. ORANGE DAY LILY.
Waste land, meadows, and along streams throughout our region. July. Eastern
U. S., as an escape from cultivation; native of Eur. and Asia.
The clustered roots have peculiar fleshy swellings which serve as storage organs.
Hemerocallis flava, the yellow day lily, is common in parks and gardens.

7. ALETRIS L. Coric-root.

Flowers 7-10 mm. long, white or ye!lowish white ............. Veeeee 1. A. farinosa,
Flowers about 5 mm. long, bright yellow ...................-...-2005- 2. A. aurea,

1, Aletris farinosa L.
Locally common in dry open pine scrub and on sterile hillsides. mostly below the

fall line; also in bogs. June. Eastern U.S.
The rosettes are evergreen and even persist on burnt-over land where the dead

cover was sparse.

2. Aletris aurea Walt.
Near Laurel, July 14, 1918 (McAtee). In sandy soil, Md. to Tex.

FLORA OF THE DISTRICT OF COLUMBIA. 123

27, CONVALLARIACEAE. Lily-of-the-valley Family.

The lily-of-the-valley, Convallaria majalis L., is commonly cultivated and tends
to persist along garden fences. It occurs as a native plant in the high mountains of
Virginia and North Carolina, though our cultivated stock is of European origin.

Flowers dioecious; leaves scalelike; plant tall, much branched. Filiform leaflike
branches (cladodes) clustered in axils of upper leaf scales...1. ASPARAGUS.
Flowers perfect; leaves present, broad; stems simple.
Leaves alternate.
Perianth segments separate; flowers in terminal racemes or panicles.
Perianth segments 6........-.-20-- 2 cece cee eee eee eee eee eee 2. VAGNERA.
Perianth segments 4........-.----.0--e0ee eee eeeeeeeee-t+-8, UNIFOLIUM.
Perianth segments united; flowers axillary, solitary or in small clusters.
4, POLYGONATUM.
Leaves whorled below the flowers.

Leaves in two whorls; perianth segments essentially similar... ... 5. MEDEOLA.
Leaves in one whorl of three; outer perianth segments green, the inner purple or
whitish. ...........-- 2-2 e eee ee eee ee eee eee 6. TRILLIUM.

1, ASPARAGUS L.
1. Asparagus officinalis L. ASPARAGUS.
Frequent as an escape from cultivation; waste places and sandy banks of streams.
The cultivated asparagus is a native of southwestern Asia, but is easily established
as a permanent member of the flora in any arable region of the United States.
The rudimentary ovaries of the staminate plant suggest a perfect flower, but they
never set seed.

2. VAGNERA Adans. Fatse SOLOMON’S-SEAL.

Flowers numerous, on very short pedicels in a terminal panicle; stamens longer than
the small (2 mm.) perianth segments; rootstock stout, fleshy; leaves ciliate, some-
what petioled...........--- 22-2022 e cece e ee eee cee ee eee eee ees 1. V. racemosa.

Flowers few, on longer solitary pedicels in a simple raceme; stamens shorter than the
longer (4-5 mm.) perianth segments; rootstock slender, long-creeping; leaves
clasping, glabrous.........-.-.-0--2-2e eee e ee eee eee eee reece eeeee 2. V. stellata.

1. Vagnera racemosa (L.) Morong.
Frequent in moist woods and thickets. May. Throughout most of the U.S. (Sma-
lacina racemosa Desf.)

2. Vagnera stellata (L.) Morong.
Rare in moist woodland; Chain Bridge, Difficult Run, and islands of the Potomac.
May. Northern N. Amer. and Eur. (Smilacina stellata Dest.)

3. UNIFOLIUM Adans.

1. Unifolium canadense (Desf.) Greene. WILD or FALSE LILY-OF-THE-VALLEY.
Locally common in swamps below the fall line, especially beyond Hyattsville.
May. Northern U.S., south to N.C. (Maianthemum canadense Desf.)

4. POLYGONATUM Adans. SoLtoMon’s-SEAL.

Flowers yellowish; free part of the filament smooth, longer than the anther.
1. P. biflorum.
Flowers green; free part of the filament granular or papillose, shorter than the anther.
Fruit greenish black..........-..----+-- seer eee eee cece eee ee 2. P. giganteum.

124 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

1. Polygonatum biflorum (Walt.) Ell.
Moist or dry woodlands; common. May, Eastern U. 8. (Salomonia biflora

Farwell.)

2. Polygonatum giganteum Dietr.
Islands of the Potomac. May. Pa. and Md. to Mont.
A large plant, up to 1.5 meters high.

5, MEDEOLA L.

1. Medeola virginiana L. CUCUMBER ROOT.
Frequent in moist woods and thickets generally. May. Eastern U. 8.
The odor of the fleshy root suggests cucumbers. The upper whorl of leaves becomes
purple and red when the fruit ripens. Known also as Indian cucumber.

6. TRILLIUM L. WakxeE-rosin.

1, Trillium sessile L.

Locally common in rich moist woodland above Little Falls on the shores and islands
of the Potomac. Apr.-May. Eastern U. §.

The forms with purple flowers and with green flowers are otherwise identical; the
latter is 7’. sessile luteum Muhl, The purple-flowered form is shown in plate 18B.

28. SMILACACEAE, Smilax Family,
1. SMILAX L. GREENBRIER.

Aerial shoots herbaceous, spineless, less than 3 meters high; underground stems slow-
growing, knotted and woody, never with long creeping rootstocks; flowers carrion-
scented; ovules 2 in a cell.

Anthers equaling the filaments; peduncles usually more than one at a node; leaves
often hastate, pale and glaucous beneath, glabrous........... 1. S. tamnoides.

Anthers shorter than the filaments; peduncles never more than one at a node;
leaves never hastate.

Leaves glabrous and glaucous beneath.......................---- 2. S. herbacea.
Leaves puberulent and green beneath................... .....3. S. pulverulenta,

Aerial shoots woody, armed with spines, at least on the main stems, usually high-
climbing; flowers not carrion-scented; ovules solitary in each cell.

Underground stems short, slow-growing, without long creeping rootstocks; plants
not at all glaucous; spines slender, black, straight, numerous below; berries
black, usually one-seeded..............202-002. 200200 ce cece eee 4. S. hispida.

Underground stems with long creeping rootstocks; at least the flowers and fruit
glaucous; spines stout; berries blue-black, usually 3-seeded.

Stem and leaves not glaucous; leaves deciduous; spines heavy, straight, never
at nodes and fewer at base of stems; stems green (drying yellowish).
5. S. rotundifolia.
Stem and leaves glaucous; leaves more or less evergreen; spines strong, recurved,
usually at nodes and more numerous at base of stem; stems dark.
6. S. glauca,

1. Smilax tamnoides L.

Swamps and wet woods; common northeast of Washington, Eastern Branch region.
June-July. Southeastern U.S. (8. tamnifolia of Ward’s Flora.)

This species can be recognized by its yellowish green color, thicker leaves, and 1-3-
seeded berries. The occurrence of more than one peduncle at a node is an interesting
difference between this and the other species.

2. Smilax herbacea L. CARRION FLOWER.

Open wooded rocky slopes; frequent in Great Falls region and in swamps of the
Eastern Branch. June-July. Northeastern U. §., south in the mountains to N. C.

FLORA OF THE DISTRICT OF COLUMBIA. 125

3. Smilax pulverulenta Michx.

Moist woodland; common in the upper Potomac and Rock Creek regions. May.
Central Atlantic states, west to Ohio Valley.

Easily distinguished from S. herbacea by the pulverulent pubescence on the under
surface of the leaves, which lack the glaucous coat. The common Potomac River form.

4. Smilax hispida Muhl. GREENBRIER.

Moist rich woodland; common in the upper Potomac and Rock Creek regions. May.
Eastern U.S.

This is the largest greenbrier of the region Its green leaves persist well into late
autumn. It does not spread rapidly underground like the other woody forms and
entirely lacks any glaucous coat. Even normally one-seeded berries are green-black.
(8. pseudo-china of Ward’s Flora contained the larger plants of S. hispida. The tubers
Ward refers to were not from Smilaz, as this species does not have tubers.)

5. Smilax rotundifolia L. HorsEBRIER.
Common everywhere. May. Eastern U. 8.

6. Smilax glauca L. CATBRIER.
Common everywhere. May-June. Eastern U.S.
This species often has tubers on the spiny rootstocks.

29, AMARYLLIDACEAE. Amaryllis Family.

This family contains numerous cultivated forms grewn as greenhouse and outdoor
ornamentals, such as Narcissus of several species among which are the daffodils, jon-
quils, narcissus, etc. (N. biflorus has been collected as an escape, but probably was a
persistent garden bulb); Polianthes tuberosa, the tuberose; Agave, century plants;
and Hippeastrum, the so-called amaryllis of the trade.

1. HYPOXIS L. Srar-GRass.
1. Hypoxis hirsuta (L.) Coville.
Frequent in grassland. May. Eastern U.S. (JD. erecta L.)

This grasslike plant is recognized by its yellow starlike flowers, and its fleshy corm
about 1 cm. thick.

30. DIOSCOREACEAE, Yam Family.
1. DIOSCOREA L. Yam.

Lower leavesin whorls of 4-7; leaves glaucous beneath when mature, usually hirtellous

with sparsely scattered hairs, sometimes almost glabrous. .......--- 1. D. glauca.
Lower leaves alternate, or the three lowest close together or indefinitely whorled;
leaves pubescent beneath...........0.-20 202s eee eee ee ee eee ee eee 2. D. villosa,
1. Dioscorea glauca Muhl. WILD YAM.

Thickets or open woods, climbing over shrubs; common. Eastern U. S.

This is the wild yam of commerce; its thick, much-branched, irregular rootstock ig
the source of the drug dioscorea.
2. Dioscorea villosa L.

Moist or low thickets; infrequent. Conn. to Md. and westward to Okla. _

Rootstocks long and slender, simple or rarely branched; inflorescence densely
many-fruited.

126 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

31, IRIDACEAE. Iris Family.

This family contains many ornamental species in common cultivation, Crocus,
Freesia, and Gladvlus being well-known genera. Species of Crocus tend to persist in
old lawns and gardens.

Flowers large, more than 4 cm. long; leaves broad.
Flowers yellow or blue; seeds dry; style branches opposite the anthers, broad, petal-

like... 2... cece cence cece eee e cece ee enenees 1. IRIS.
Flowers orange; seeds fleshy; style branches alternate with the anthers, slender-
filiform... 2.0.2... 2 eee cece cece eee eee eceeeeees 2. GEMMINGIA.
Flowers small, less than 2 cm. long; leaves grasslike. Style branches alternate with
the anthers, filiform ..............0..0. 00000 c cece e eee ence 3. SISYRINCHIUM.
1. IRIS L.

Stems tall, leafy, usually several-flowered, more or less branching; perianth tube much
shorter than the sepals, these larger than the petals and not crested.
Flowers blue... ......0.....000 222 cccee cece ee eee eee wee cece ee eee 1. I. versicolor.
Flowers yellow ........ 2.2.22... 20.0000 e cece cece eee eeceeceeees 2. I. pseudacorus.
Stems low, 20 cm. high or less, 1-3-flowered; perianth tube long and slender, the violet-
blue sepals and petals nearly equal.

Leaves lanceolate; sepals crested. ...............0.0ceeeeeeeeceeeeee 3. I. cristata.
Leaves linear; sepals not crested...............0ceceeeececeeeceeceeees 4. I. verna.
1. Iris versicolor L. BLvueE FLAG.

Open swamps and bogs. May. Eastern N. Amer.
The flowers are shown in plate 19B.

2. Iris pseudacorus L. YELLOW FLAG.
Established along the Potomac marshes below Washington. May. A local escape
from cultivation throughout the eastern U. 8.; native of Eur.

3. Iris cristata Ait. CRESTED IRIS.
Stream margins and low wet woodland; along the Potomac above Washington; rare.
May. Southeastern U. S., north to Md.
A plant in flower is shown in plate 15B.
4. Iris verna L. SPRING IRIS.
Dry sandy woods near swamps; locally abundant in one or more localities, Bladens-
burg to Ammendale. May. Southeastern U. S., north to Pa.
Many cultivated species and hybrids of Iris are found in gardens. J. germanica L.
and others tend to persist in old gardens and dumps.

2. GEMMINGIA Fabr.

1. Gemmingia chinensis (L.) Kuntze. BLACKBERRY LILY.
Escaped from cultivation along roadsides and fences, preferring rich, well-drained
soil. July. Naturalized from Asia in the eastern U.S. (Pardanthus chinensis Ker.)
When the capsule dehisces the mass of black fleshy seeds suggests a large black-
berry.
3. SISYRINCHIUM L. BLUE-EYED GRass.

Stems simple, with a terminal sessile spathe, narrowly wing-margined, drying green.

1. S. mucronatum.
Stems branched, or if simple broadly winged.

Stems broadly winged.

Stems either simple or branched; plants drying green...... 2. S. intermedium.
Stems branched above, bearing two or more pedicellate spathes; plants darken-
ing in drying. Pedicels spreading or recurved..........-- 3. S. gramineum.

Stems narrowly winged; pedicels not recurved; plants not darkening in drying.
4. S. atlanticum.

FLORA OF THE DISTRICT OF COLUMBIA. 127

1. Sisyrinchium mucronatum Michx.

Meadows and fields; common north and west of Washington. May. Northeastern
U. S8., south to Va.

Distinguished from the other species by its sessile spathes.

2. Sisyrinchium intermedium Bicknell.

Low wet soil along the Potomac and Rock Creek; rare. May. Central Atlantic
states.

This doubtful species is included on Bicknell’s identification. It is perhaps a
form of S. mucronatum.

3. Sisyrinchium gramineum Curtis.

Wet meadows and damp woods; frequent. May-June. Eastern U.S. (8S. anceps
of Ward’s Flora; S. graminoides Bicknell.)

This species can be readily recognized by the black color it takes when wilted.

4. Sisyrinchium atlanticum Bicknell.
In or near marshes; common northeast of Washington. May-June. Atlantic

Coast Region.
32. ORCHIDACEAE. Orchis Family.

Inflorescence a spirally twisted spike. Flowers white or greenish white.
9. IBIDIUM.
Inflorescence not spirally twisted.
Leaves not present (or if present much withered) at flowering time.
Roots coral-like; plants without green coloring matter; leaves reduced to brown-
ish sheaths........-..... 2.20 eee eee eee eee ee eee 13. CORALLORREHIZA.
Roots not coral-like; plants with green coloring matter, producing a leaf in the
fall, this persisting throughout the winter, but usually withering before
flowering time.

Leaf plaited, green on both sides or sometimes purplish beneath near the base,
turning brown in withering; scape bracted, purplish, appearing in May;
lip not spurred... ..-....--- eee eee eee eee eee eee ees 16. APLECTRUM.

Leaf smooth, green above and purple beneath, turning bright scarlet in wither-
ing; scape bractless, straw-colored, appearing in July; lip spurred.

17. TIPULABIA.
Leaves present (fresh and green) at flowering time.
Leaf only one (bract sometimes leaflike in Pogonia).

Leaf elliptic or ovate, borne near the middle of the stem.

Flowers solitary, or rarely two, in the axil of a large bract, rosy pink or white;

plants growing in bogs. ......----------+--2-e+ee eee eee 4, POGONIA.
Flowers many, small, in a short raceme with minute bracts, greenish yellow;
plants growing in woods.......-.------++++++--++-+---+-> 14. MALAXIS.

Leaf linear-lanceolate, basal.
Flower solitary; perianth segments close together, rosy purple; lip pendent;

plant 15-30 cm. tall, flowering in May......----.------- 8. ARETHUSA.
Flowers several; perianth segments spreading, rosy pink; lip erect; plant
20-45 cm. tall, floweringin July.......--.--.-.-..... 7. LIMODORUM.

Leaves more than one (rarely only one in Habenaria and Orchis).
Stem leafy only at the base.
Flower solitary, large. Lip a moccasin-shaped sac, divided down the middle.
° 1, CYPRIPEDIUM.
Flowers more than one.
Inflorescence spikelike; lip saccate; leaves several, white-netted, thick,
remaining green through the winter. Flowers greenish white.
11. PERAMIUM.

128 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Inflorescence racemose; lip not saccate; leaves usually two, not white-
netted nor evergreen.

Bracts longer than the flowers; perianth united into a magenta-pink
hood, the lip white; leaves elliptic, dark green; plants of low rich
006 2. ORCHIS.

Bracts minute; flowers greenish yellow or madder-purple; leaves ovate,
light green; plants of dry woods or damp rocky ravines.

15. LIPARIS.
Stem leafy above the base.

Leaves opposite or whorled.
Leaves a single pair near the middle of the stem; flowers in a slender

raceme, small, greenish.................2.-20eeeeeee 12. OPHRYS.
Leaves usually 5 in a whorl at the top of the stem; flowers one or two,
large, madder-purple......................00ceeeeeeee 5. ISOTRIA.

Leaves alternate.
Flowers few, not in racemes.
Leaves large, plaited; flowers large, the lip a pink or yellow inflated sac.
1. CYPRIPEDIUM.
Leaves small, not plaited; flowers small, the lip not saccate.

. 6. TRIPHORA.
Flowers many, in racemes.

Lip saccate, not spurred; flowers madder-purple; basal leaves con-
spicuously nerved, broadly ovate, reducing upward to lanceolate

bract8......... 2.2. e cece cece eee cece eee eees 9. SERAPIAS.
Lip not saccate, spurred; flowers not madder-purple; leaves not con-
spicuously nerved, all lanceolate................. 8. HABENARIA,

1. CYPRIPEDIUM L. lLapy’s-s.rpprEr.

Leaves two, at the base of the stem; lip rosy purple, the opening linear. .1. C. acaule.
Leaves several, borne on the stem; lip yellow, the opening round and open.
2. C. parviflorum.

1. Cypripedium acaule Ait. MoccasIN FLOWER.
Bogs, rich woods, or dry pine hills. May. Eastern N. Amer. (Fissipes acaulis
Small.)
Nearly white forms are found occasionally, especially in bogs. A plant in flower is
shown in plate 20B.

2. Cypripedium parviflorum Salisb. YELLOW LADY’S-SLIPPER.

Banks of ravines or rich woods. May. Northern and eastern N. Amer. (C. hir-
sutum of Britton’s Manual.)

The large-flowered form (C. pubescens Willd.) is not so common in our region as is
the typical small-flowered form.

Cypripedium hirsutum Mill. was reported from our region by Brereton. (C. specta-
bile Salisb.; C. reginae Walt.)

°
2. ORCHIS L.

1. Orchis spectabilis L. SHOWY ORCHIS.

Low rich woods. May. Eastern U.S. (Galeorchis spectabilis Rydb.)

Sometimes found with only one leaf developed, which would place these plants in
the related species, O. rotundifolia Banks, in most manual keys. Our species has
large bracts longer than the flowers, while 0. rotundifolia has very small bracts.
Plants in flower are shown in plate 20A.

FLORA OF THE DISTRICT OF COLUMBIA. 129

3. HABENARIA Willd.

Lip not fringed nor deeply lobed; racemes narrow; flowers small and greenish.
Lip hastate, with a tubercle in the center at the base; spur slender, straight.
1. H. flava.
Lip 3-toothed at the apex, not tubercled at the base; spur clavate, curved.
2. H. clavellata.
Lip fringed or deeply lobed; racemes broad; flowers large and showy.
Lip fringed but not lobed.
Flowers orange-yellow.
Lip ovate, about 5 mm. long; spur about half as long as the ovary.

3. H. cristata.

Lip oblong, about 10 mm. long; spur longer than the ovary.....- 4. H. ciliaris.

Flowers white.........---- 2-2-0 e cece cece reer eee ers eeeee 5. H. blephariglottis.
Lip deeply 3-lobed.

Flowers greenish white; lobes of the lip lacerate-fringed..-......--- 6. H. lacera.

Flowers violet-purple; lobes of the lip cut-toothed, not fringed.
7. H. peramoena.

1. Habenaria flava (L.) A. Gray.
Moist meadows. June. Eastern U. 8S. (H. virescens Spreng.; Perularia flava
Farwell.)

9. Habenaria clavellata (Michx.) Spreng.
Bogs, usually in shade. July. Eastern U. 8. (i. tridentata Hook.; Gymnaden-
iopsis clavellata Rydb.)

3, Habenaria cristata (Michx.) R. Br.
Known from only one locality, a bog near Suitland. Southern states, north to N. J.
(Blephariglottis cristata Raf.)

4, Habenaria ciliaris (L.) R. Br. YELLOW FRINGED ORCHIS.
Bogs, usually in open places. July-Aug. Eastern U. 8. (Blephariglottis ciliaris
Rydb.)

A pale form has been found several timesin the vicinity of Hyattsville.

5. Habenaria blephariglottis (Willd.) Torr. WHITE FRINGED ORCHIS.
Bogs, usually with the last species, July-Aug. (Blephariglottis blephariglottis
Rydb.)
6. Habenaria lacera (Michx.) R. Br. RAGGED FRINGED ORCHIS.
Fairly common in damp meadows. June. Eastern U. 8S. (Blephariglottis lacera
Farwell.)
7, Habenaria peramoena A. Gray. PuRPLE ORCHIS.
Ditches and wet meadows. July-Aug. N. J. to Mo. and Ala. (Blephariglottis
peramoena Rydb.)
Our handsomest orchid.
4. POGONIA Juss.

1, Pogonia ophioglossoides (L.) Ker. ROSE POGONIA.
Bogs. June. Eastern U.S.
Flowers occasionally almost white; fragrance delicate and delightful.
Pogonia divaricata (L.) R, Br. is listed by Brereton.

69289—19—_9

130 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.
5. ISOTRIA Raf.

1, Isotria verticillata (Willd.) Raf.
Low rich woods. May-June. Eastern U.S. (Pogonia verticillata Nutt.)
Sometimes confused with Medeola virginiana, which has a flocculent-woolly green
stem, while Jsotria has a glabrous purple stem. This species has the reputation of
disappearing from its usual haunts for several years in succession and then reappearing.
Its coloring is very highly protective.

6. TRIPHORA Nutt.

1. Triphora trianthophora (Swartz) Rydb.

Low rich woods along the Potomac. Eastern U, S. (Pogonia trianthophora B.S. P.;
P. pendula Lindl.) ;

While possibly not our rarest orchid, this little plant is certainly the hardest to find.

7. LIMODORUM L.

1. Limodorum tuberosum L. GRASS-PINK.
Bogs; usually associated with Pogonia ophioglossoides. Eastern U. S. (Calopogon
pulchellus R. Br.)
Pale, nearly white forms are occasionally found. Strikingly peculiar in having the
lip erect, while all our other orchids have pendent lips.

8. ARETHUSA L.

1. Arethusa bulbosa L, ARETHUSA.
Gravel bogs near Suitland and Hyattsville; rare. May. Eastern N. Amer.

9. SERAPIAS L.

1. Serapias helleborine L.

Our only introduced orchid, well established in the Soldier’s Home woods, probably
persisting from the planting around some old homestead, J uly. Native of Europe.
(Lpipactis viridiflora Reichenb.)

10. IBIDIUM Salisb. Lapres’-rresses.

F lowers in several ranks.
Lip quadrate, yellowish; lower leaves oblong-lanceolate.......1, I. plantagineum.
Lip oblong-ovate, white or greenish white; leaves all narrowly lanceolate.
Flowers only slightly fragrant, apparently arranged in four vertical rows; bracts
curved, shorter than the flowers; plants not stoloniferous....... 2. I. cernum,
Flowers decidedly fragrant, in evident spiral rows; bracts erect, equaling or
exceeding the flowers; plants producing stolons sometimes 10 cm. long.

3. I. odoratum.,
Flowers in one rank.

Leaves persistent, lanceolate....... wee eee eee cece cece ee ee eee 4. I. vernale.
Leaves soon withering, ovate.
Roots fascicled; lip green, with white margin; flowering in July.......5. I. gracile.
Root usually solitary; lip all white; flowering in September.......... 6. I. beckii.

1. Ibidium plantagineum (Raf.) House.

Flats below Chain Bridge. May. Northern states, south to Va. (Spiranthes lucida
Ames; 8. latifolia Torr.; Gyrostachys plantaginea Britton.)
2. Ibidium cernuum (L..) House.

Wet meadows and margins of bogs. Sept. Eastern U. 8. (Spiranthes cernua L,
Rich.; Gyrostachys cernua Kuntze.)

FLORA OF THE DISTRICT OF COLUMBIA. 131

3. Ibidium odoratum (Nutt.) House. FRAGRANT LADIES’ -TRESSES.
Swamps; Alexandria and Dyke. Sept. Along the coast, Va. to Tex. (Spiranthes
odorata Lindl.; Gyrostachys odorata Kuntze.)
The stolons spread out under water from the base of the plant for several inches and
end in a large green bud at the surface.

4, Ibidium vernale (Engelm. & Gray) House.
Dry meadows. July. Eastern U.S. (Spiranthes vernalis Engelm. & Gray.)
5. Ibidium gracile (Bigel.) House.
Open meadows in dry pine and oak woods. July-Aug. Eastern U.S. (Spiranthes
gracilis Beck; Gyrostachys gracilis Kuntze.)
6. Ibidium beckii (Lindl.) House.

Open meadows and dry woods. Aug.—Sept. Coastal Plain, Mass. to Tex. (Spiran-
thes beckii Lind1.; §. simplex A. Gray; Glyrostachys simplex Kuntze.)

11. PERAMIUM Salisb. RaTTLESNAKE PLANTAIN.

1. Peramium pubescens (Willd.) MacM.
Pine and oak woods. Aug. Eastern U. 8. (Goodyera pubescens R. Br.; Epipactis
pubescens A. A. Eaton.)

There is a specimen of Peramium ophioides (Fernald) Rydb. in the herbarium.
labeled ‘“‘N. W. Branch, Sept. 28,’’ but the data are regarded as doubtful.
12. OPHRYS L. Twaysiave.
1. Ophrys australis (Lindl.) House.
Bladensburg Swamp. May. N.Y. to La. (Jvstera australis Lind.)

13. CORALLORRHIZA R. Br. Cora.-roor.

Lip with a small lobe on each side at the base..............--------- 1. C. maculata.
Lip not lobed at the base.
Lip denticulate, long-clawed; plant flowering in May............ 2. C. wisteriana.

Lip notched at the apex, short-clawed; plant flowering in August.

8. C. odontorhiza.
1. Corallorrhiza maculata Raf.

Medium rich oak woods. Aug.—Sept. Throughout the U. S. (C. multiflora
Nutt.)
2. Corallorrhiza wisteriana Conrad.

Apparently confined to rich woods along the Potomac. May. Eastern U.S.

8. Corallorrhiza odontorhiza (Willd.) Nutt.
Medium rich woods, often under beech. Eastern U.S.

14. MALAXIS Soland. AppgErR’s-MouTH.

1. Malaxis unifolia Michx.

Along runs in ravines of dry woods. July. Eastern U.S. (Microstylis ophioglos-
soides Nutt.; Achroanthes unifolia Raf.)

15. LIPARIS L. Rich. TwayBuLabDe.

Lip wedge-obovate, purple............0.0-0. ee eee eee cece cece ee eee 1. L. liliifolia.
Lip oblong-ovate, yellowish green...........2222-.2.-22--0--2-2-2-0------ 2. L. loeselii.
1. Liparis liliifolia (L.) L. Rich.

Medium rich oak woods. June. Eastern U.S. (Leptorchis liliifolia Kuntze.)
2. Liparis loeselii (L.) L. Rich.

Rocky ravines and rich woods. June. Northern states, south to Md. (Leptorchis
loeselit MacM.)

132 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

e 16. APLECTRUM Torr.

1. Aplectrum hyemale (Muhl.) Torr. Purty-roor,
Rich woods. May-June, Northern and eastern N. Amer. (A. spicatum B.S. P.)

17. TIPULARIA Nutt. CRANE-FLY ORCHIS.

1. Tipularia unifolia (Muhl.) B.S. P.
Medium rich oak woods. July-Aug. Eastern U.S. (7. discolor Nutt.)

33. SAURURACEAE. Lizard’s-tail Family.

1. SAURURUS L.

1. Saururus cernuus L. LIZARD’S-TAIL,
Swamps and shallow water; common. June-Aug. Eastern U.S.
A rather showy tall plant with heart-shaped leaves and long slender recurved
spikes of small white flowers. It has a ginger-like odor. A characteristic colony of
plants is shown in plate 21.

34, SALICACEAE. Willow Family.

Bracts of the catkins entire or obscurely toothed; stamens few (1-10); stigmas short;

bud scale 1; leaves much longer than broad.............-.-2.-..-.--- 1. SALIX.
Bracts deeply and sharply toothed; stamens numerous; stigmas elongate; bud
scales several; leaves broad, often as broad as long............... 2. POPULUS.

1. SALIX L. WILLow.

The following species are often cultivated, and isolated individuals may be found
in waste places: Salix purpurea L., S. pentandra L., and S. caprea L,

KEY TO SPECIMENS WITH CATKINS.

Catkins stalked, appearing with the leaves or after them; capsule glabrous (hairy
when young in S. interior).
Catkins appearing long after the leaves, often clustered, terminating long leafy
twigs. Leaves linear or broadly linear, remotely and minutely toothed, green
on both sides, more or less hairy when young; stamens 2; shrub.
1. 8. interior.
Catkins appearing with the leaves, solitary, terminating short leafy stalks.

Scales of the catkins brown, at least at the tip, persistent; filaments glabrous.
Catkins nearly sessile; leaves lanceolate or broadly lanceolate, closely
serrate, glabrous, pale beneath; shrub....................-----7. 8, cordata.

Scales pale yellow, deciduous; filaments hairy.

Stamens 3-7; pedicels 1-3 mm. long; shrubs or small trees.

Leaves narrowly lanceolate, green on both sides...........----.-- 2. S. nigra.
Leaves broader, glaucous beneath.........-. bene cece ee ceeeeee 3. S. wardi.
Stamens 2; pedicels less than 1 mm. long; trees. Leaves lanceolate, glaucous

beneath.
Twigs long, pendulous, tough. Capsule nearly sessile; leaves linear-lanceo-
late, glabrous, minutely serrate..............-- seeeee 6. S. babylonica.

Twigs short, not pendulous, fragile at the base.
Capsule short-pediceled; leaves glabrous or nearly so, coarsely serrate;
petioles glandular................-..-22--------+-+--- 4. S. fragilis.
Capsule sessile; leaves usually silky, even in age, finely serrate; petioles
scarcely glandular..........2...2 0.222222 2 eee ee ee eee eee 5. S. alba.

FLORA OF THE DISTRICT OF COLUMBIA. 133

Catkins sessile, appearing before the leaves; capsule pubescent or woolly. Scales of
the catkins black, long-hairy.
Catkins slender; capsule 3-4 mm. long, silvery-pubescent; leaves silvery-silky and
glaucous beneath; treelike shrub......-------++2+++-++22+e000+ 8. S. sericea.
Catkins stout; capsule 6-8 mm. long, woolly; leaves oblanceolate, woolly beneath;

low shrubs. .
Catkins oval-oblong, 1-3 cm. long; leaves broadly oblanceolate, 5-8 cm. long;

shrub 1 meter high or more..........-.--------++eet eee rete 9. S. humilis.
Catkins nearly spherical, 0.5-1.5 cm. long; leaves narrowly oblanceolate, 2-5
em. long; shrub about 0.5 meter high....-..------+-++++++-+- 10. S. tristis.

KEY TO SPECIMENS WITH LEAVES ONLY.

Leaves glabrous when fully grown.
Leaves green on both sides.
Leaves linear or broadly linear, remotely and minutely toothed...1, S. interior.
Leaves narrowly lanceolate, closely serrate. .....------+-+++++++-+--- 2. S, nigra.
Leaves pale or glaucous beneath.
Twigs long, slender, pendulous; leaves linear-lanceolate, minutely serrate.
6. S. babylonica.
Twigs short, not pendulous; leaves lanceolate.
Stipules very small, inconspicuous, early deciduous.

Petioles glandular; leaves coarsely serrate....------+-+++---- 4. 8. fragilis.
Petioles usually without glands; leaves finely serrate......-.-.--- 5. S. alba.
Stipules large, conspicuous, usually persistent, especially on young shoots.
Leaves narrowly lanceolate, very glaucous beneath.......--.--- 3. S. wardi.
Leaves broadly lanceolate, slightly glaucous beneath. ......-- 7. S. cordata.

Leaves hairy when fully grown.

Leaves silvery-silky beneath or on both sides. :
Leaves linear or broadly linear, remotely and minutely serrate... .- 1. S, interior.
Leaves lanceolate, closely serrate.

Twigs fragile; leaves thinly or closely silky on both sides; introduced tree.

5. S. alba.

Twigs not fragile; leaves thinly silky beneath; native shrub....-. 8. S. sericea.
Leaves gray-tomentose, especially beneath.

Leaves broadly oblanceolate, 5-8 cm. long..-.---.-.---+-+++----- 9. S. humilis.

Leaves narrowly oblanceolate, 3-5 em. long.....---.-------+++++- 10. S. tristis.

1, Salix interior Rowlee. SANDBAR WILLOW.
Along the upper Potomac. Apr.-May. Eastern N. Amer. (S. longifolia Muhl.)

2. Salix nigra Marsh. BLACK WILLOW.
Along streams; common. Apr.-May. Widely distributed in N. Amer. (S.
nigra falcata Torr.)
A hybrid between this and S, wardi has been found along the canal near High
Island.

8. Salix wardi Bebb. WARD’S WILLOW.
Rocky banks and flats along the upper Potomac; common. Apr.-May. Southern
states, north to Md. (S. nigra wardi Bebb.)
The species was described from specimens obtained by Ward near Chain Bridge.
4, Salix fragilis L. CRACK WILLOW.
Along the Eastern Branch, Fourmile Run, and Hunting Creek. Apr.-May.
Native of Eur.; often cultivated and becoming naturalized in eastern N. Amer.
5. Salix alba L. WHITE WILLOW.
Established in a few places along streams. Apr.—May. Native of Eur.; culti-
vated or naturalize eastern N. Amer.

134 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

6. Salix babylonica L. WEEPING WILLOW.

Along the upper Potomac; infrequent. Apr.-May. Native of Asia; cultivated
and naturalized in eastern N. Amer.

7. Salix cordata Muhl.

Along the Potomac, Eastern Branch, and Hunting Creek. Apr.-May. Widely
distributed in N. Ambr.

A hybrid between this and 8. sericea is found occasionally.

8. Salix sericea Marsh. SILKY WILLOW.
Along streams; common. Apr.May. Eastern N. Amer.

9. Salix humilis Marsh. PRAIRIE WILLOW.
Dry fields, thickets, and open woods; frequent. March-Apr. Eastern N. Amer.

10. Salix tristis Ait. DWARF PRAIRIE WILLOW.

Dry fields and woods, chiefly eastward. Apr.-May. Eastern N. Amer.

2. POPULUS L. Poptuar.

Leaves deltoid or cordate-deltoid, glabrous on the surfaces, ciliate; buds glabrous, resi-
nous; floral bracts falling early.........0.020.000.0.0222-2---. 1. P. virginiana.
Leaves rounded, oval, or cordate-oval; buds neither glabrous nor resinous; {floral
bracts versistent,
Leaves on ihe young branches cordate-ovate, 15-20 cm. long or more.
Leaves crenate, long-petioled, auriculate at bage, the auricles overlapping.

long, sericeous at first, glabrous in AMO... lee 2. P. grandidentata.
Leaves on the young branches broadly cordate-ova‘e, rarely over 10 cm. long, irreg-
ularly toothed or lobed.

Leaves on the young branches deeply 5-lobed, dark-green above, white-woolly
beneath; normal leaves with more or less persistent wool; petioles shorter than
the blades. 2... cece cece eee eee. 8. P. alba.

Leaves on the young branches irregularly toothed, not deeply lobed, silvery-
canescent or woolly; normal leaves commonly ovate, acute, canescent,
becoming glabrous; petioles equaling or exceeding the blades.

4. P. canescens.

1. Populus virginiana Fouger. CorTrronwoop.
River bottoms and low places. Apr. Middle Atlantic states. (P. monilifera Ait.)
Populus italica Moench (P. dilatata Ait.; P. nigra italica DuRoi), the Lombardy

poplar, is extensively planted; readily recognized by its very broad, deltoid, abruptly

acuminate root-shoot leaves and erect fastigiate branches, Native of Eur.

Populus nigra L., the black poplar, is occasionally planted. Native of Eur. The
normal leaves are rhombic-acuminate, 5-8 cm. long, the branches spreading and in
age horizontal.

Populus eugenet Simon-Louis (P. montlifera of authors, not Ait.), the Carolina
poplar, is extensively planted in our streets and parks. It has an excurrent trunk and
spreading branches; the leaves are triangular-ovate, broadest below the middle, long-
acuminate, those of the root shoots more or less deltoid, the teeth in both cases being
incurved.

2. Populus grandidentata Michx. LARGE-TOOTHED ASPEN.
Deciduous woods. Apr. Northern states, south to N.C.

Populus tremuloides Michx., the American aspen, has escaped from cultivation near
Chevy Chase Lake (Mazon & Standley). Can. to Pa. and Nebr. Readily recognized
by its broadly ovate or orbicular, crenulate, abruptly acuminate leaves, 3-6 cm. long.

FLORA OF THE DISTRICT OF COLUMBIA. 135

8. Populus alba L. WHITE or SILVER POPLAR.

Abandoned nurseries and old fields. March. Native of Eur. and Asia.

Populus alba bolleana Masters, Bolle’s poplar, from Turkestan, is distinguished
from the species by its pyramidal form and fastigiate branches. The leaves are larger
and more deeply lobed than in the type and the lobes are incisely toothed.

4. Populus canescens (Ait.) J. E. Smith. GRAY POPLAR.

In cultivation and escaped. March. Native of Eur.

Populus tacamahaca Mill. (P. candicans Ait.; P. balsamifera candicans A. Gray),
the Balm of Gilead, is cultivated. Native of northern U.S. It is recognized by its
broadly ovate, crenulate leaves, 6-20 cm. long, silvery beneath. .

5. Populus heterophylla L. SWAMP POPLAR.

Low ground and swamps; above Great Falls (Bartlett). Apr. Eastern states, south
to Ga.

35. MYRICACEAE. Bayberry Family.

Leaves entire or toothed, without stipules; fruit a small drupe, usually covered with

2 1. MYRICA.
Leaves pinnately lobed, with stipules; fruit nutlike, surrounded by a burlike invo-
LUCTO. 0... 2 ee eee ee eee teen e eee e tenner eres 2. COMPTONIA.

1. MYRICA L.
1. Myrica carolinensis Mill. BAYBERRY.

Pine barrens and swamps; Silver Springs and throughout Prince Georges County;
Eastern N. Amer, (J. cerifera of Ward’s Flora.)

2, COMPTONIA Banks.

1. Comptonia peregrina (L.) Coulter. SWEET FERN.
Near the Reform School; rare. Northern and eastern N. Amer. (Myrica aspleni-
folia L.)
36. JUGLANDACEAE, Walnut Family.

Leaflets 11-23, oblong-lanceolate, acuminate; staminate aments solitary; husk of the
? oD b] ? y ?

fruit indehiscent..........-----2+-----e eee eee cece eee eee 1. JUGLANS.
Leaflets 5-9, unequal, the lower pairs commonly shorter; staminate aments in clusters;
husk dehiscent... 2.2.2.0... 2 eee eee eee ee eee ee ee eee 2. HICORIA.

1. JUGLANS L.

Leaflets with an asymmetric base; fruit globose, 4-6 cm. in diameter...... 1. J. nigra.

Leaflets with a nearly symmetric base, the terminal leaflet on a stalk 1 em. long or

more; fruit oblong, 4-7 em. long, 3-4 em.in diameter.......------- 2. J. cinerea.

1. Juglans nigra L. BLACK WALNUT.
Rich deciduous woods. Apr.-May; fr. Oct. Eastern U.S.

2. Juglans cinerea L. BUTTERNUT.

Rich woods; Potomac valley above Georgetown. Apr.—May; fr. Oct. Eastern N.
Amer.

Juglans regia L., the cultivated English walnut, is distinguished by its elliptic-
oblong, unequal-sided, entire leaflets. Native of Asia.

2. HICORIA Raf.

Rachis of leaves perfectly glabrous. Bud scales numerous, imbricate.
Leaflets 3-7, oblong or oblong-lanceolate; fruit obovoid, 4-5 em. long, the husk
thin, the nut angled, thick-shelled, bitter..........--------------3- H. glabra.
Leaflets 5-7, oblong or ovate-lanceolate; fruit globose or nearly so, 2.5 cm. in diame-
ter or less, the husk thin, the nut not angled, thin-shelled, sweet.
4. H. microcarpa.

136 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Rachis of leaves puberulent to densely hirsute (at least when young).

Rachis densely hirsute. Leaflets 7-9, oblong-lanceolate or oblanceolate, acuminate;
fruit globose or oblong, 3.5-7 cm. long, the husk thick, the nut angled, pointed,
thick-shelled, sweet; bud scales numerous, imbricate.............-- 2. H. alba,

Rachis pubescent or puberulent (when young).

Bud scales few, valvate; leaflets 7-9, lanceolate or oblong-lanceolate, acuminate,
puberulent when young; fruit nearly globose, 2.5-3.5 em. in diameter, the
husk thin, the nut angled, thin-shelled, 2-2.5 em. long, very bitter,

1. H. corditormis.

Bud scales numerous, imbricate; leaflets oblong, oblong-lanceolate, or obovate;
fruit globose or nearly so, 3.5-6 cm. in diameter, the husk thick, the nut
thin-shelled, sweet. Rachis and twigs puberulent, becoming glabrous,

5. H. ovata.

1. Hicoria cordiformis (Wang.) Britton. BItreRNvT,
Moist woods and low places. May; fr. Sept. Eastern U. 8. (Carya amara Nutt.;

H, minima Britton.)

2. Hicoria alba (L.) Britton. MockERNUT.
Dry deciduous woods. May; fr. Aug—Sept. Eastern U. S. (Carya tomentosa

Nutt.; C. alba K. Koch.)

8. Hicoria glabra (Mill.) Britton. PIGNUT HICKORY.
Deciduous woods. May; fr. Aug. Eastern U.8. (Carya porcina Nutt.; C. glabra

Spach.)

4. Hicoria microcarpa (Nutt.) Britton. SMALL-FRUITED HICKORY.
Deciduous woods. May; fr. Oct. Northern states, south to Ga. (Carya micro-

carpa Nutt.)

5. Hicoria ovata (Mill.) Britton. SHAG-BARK OF SHELL-BARK HICKORY.
Deciduous woods; Potomac valley, May; fr. Oct.-Nov. Eastern U. 8. (Carya

alba Nutt.; C. ovata K. Koch.)

37. BETULACEAE. Birch Family.

Seeds winged, small; staminate flowers 3 or more in the axil of each bract; fruit ovoid
or oblong, 1.5 cm. long or smaller.
Plants shrubs (rarely trees); leaves obovate or oval, obtuse, serrulate. Fruiting

catkins persistent...............0-0 002 eee eee eee eee eee eee eee 4, ALNUS.
Plants trees, mostly with peeling bark; leaves of an ovate or ovate-oblong type.
5. BETULA.

Seeds not winged; staminate flowers solitary in the axil of each bract; fruit various.

Plants shrubs; twigs warty, sparingly glandular-pubescent; leaves broadly cordate-

ovate, doubly serrate, 10 cm. long or less. Pistillate flowers clustered; fruit

a nut inclosed in a laciniate involucre composed of two bracts..8. CORYLUS.

Plants trees; twigs smooth, sparingly warty, or pubescent; leaves ovate-oblong,

cordate or rounded at the base, taper-pointed.

Fruiting axis 5 cm. long or more; fruiting bracts foliaceous, 3-lobed, the lateral
lobes small, the middle one oblong, serrulate, 2.5 cm. long or less.

1. CARPINUS.

Fruiting axis 3 cm. long or less; fruiting bracts becoming saclike, bladdery,

inclosing the nut.........22.2. 2.2 ee eee eee 2, OSTRYA.

1, CARPINUS L.

1. Carpinus caroliniana Walt. AMERICAN HORNBEAM. BLUE BEECH.
Along streams and in low ground. Apr.; fr. Aug. Eastern N. Amer.

FLORA OF THE DISTRICT OF COLUMBIA. 137

2. OSTRYA Scop.

1. Ostrya virginiana (Mill.) Willd. Hor HORNBEAM. IRONWOOD.
Woods; Potomac valley. Apr.; fr. July. Eastern N. Amer.

3. CORYLUS L.

1. Corylus americana Walt. HAZELNUT.
Low places. March; fr. Aug. Eastern U.S.

4. ALNUS Hill.

1. Alnus rugosa (DuRoi) Spreng. ALDER.
Swamps and low ground. March. Eastern U. S. (A. serrulata Willd.)

5. BETULA L. Brrcu.

Leaves rhombic-ovate; bark yellow; twigs grayish, pubescent.....-.---- 1. B. nigra.
Leaves ovate-oblong, cordate; bark brown; twigs glabrous or nearly so....2. B. lenta.

1. Betula nigra L. BLACK, RED, OF RIVER BIRCH.
Along streams and in low wet places. Apr.; fr. May. Eastern U. 5.

2. Betula lenta L. CHERRY Or SWEET BIRCH.
Bluffs along the Potomac above Cabin John. Apr.; fr. May. Eastern U. 8.

38. FAGACEAE. Beech Family.

Leaves not straight-veined, entire, crenate, lobed, or pinnatifid; fruit an acorn
(1-seeded nut) partially inclosed in a cuplike involucre. Staminate flowers in
slender pendulous aments; pistillate flowers borne singly or in clusters.

| 3. QUERCUS.

Leaves straight-veined, uniformly serrate, oblong-lanceolate to ovate-oblong or

oblanceolate; fruit not an acorn.
Leaves ovate-oblong; staminate flowers in globose long-stalked heads; fruit (bur)
ovate, 1.5 cm. long or less, the involucre prickly, splitting into 4 valves; nut
2, 3-angled; trees with smooth, light gray bark....--.---+--+------ 1. FAGUS.
Leaves oblong-lanceolate to oblanceolate; staminate flowers in long slender aments,
in separate clusters or in the upper part of the pistillate aments; fruit (bur)
globular, 2.5-7 cm. in diameter; nuts 2 or 3 or more, inclosed in a densely
prickly involucre; trees or shrubs....----+---+-+++++erecertt- 2, CASTANEA.

1. FAGUS L.
1. Fagus grandifolia Ehrh. BEECH.
Deciduous woods. Apr.—May; fr. Sept—Oct. Eastern N. Amer. (F. ferruginea
Ait.)
2. CASTANEA Hill.
Plants trees; leaves 10-20 cm. long or more, oblong-lanceolate, glabrous at maturity.
Bur about 7 cm. in diameter.......---------++- eee reer errr tte 1. C. dentata.
Plants shrubs; leaves densely white-pubescent or tomentulose beneath, oblong-
lanceolate or oblanceolate.

Leaves about 10 cm. long; bur 2.5 cm. long or smaller....-...-------- 2, C. pumila.
Leaves 10-20 em. long or more; mature fruit unknown....--------- 3. C, neglecta.
1. Castanea dentata (Marsh.) Borkh. JHESTNUT.

Deciduous woods. June; fr. Sept.-Oct. Eastern U. S. (C. vulgaris americana
A. DC.)

2, Castanea pumila (L.) Mill. ° CHINQUAPIN.
Deciduous and coniferous woods. June; fr. Sept.—Oct. Southern states, north

to Pa.

138 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

8. Castanea neglecta Dode.

With the preceding species near Upper Marlboro. June, The Upper Marlboro
specimens have the leaves of C. dentata and the inflorescence of C. pumila, probably
they represent a hybrid between those species.

8. QUERCUS L. Oak.

Leaves entire, linear to oblong-lanceolate.
Leaves linear-lanceolate; cup saucer-shaped, 8-12 mm. broad; acorn about 10 mm.

high... 2.0.0.2 cece cee cece cence ceeeee 1, Q. phellos,
Leaves oblong-lanceolate; cup hemispheric or nearly so, 10-15 mm. broad; acorn
15 mm. high or smaller. s..........00. 0.02 c eee cece eee eee 2, Q. imbricaria.

Leaves few-toothed to deeply lobed.
Leaves very broad toward the apex, 3 or 5-lobed, abruptly contracted toward the
base; cup hemispheric, 10-15 mm. broad; acorn ovoid...... 3. Q. marilandica.
Leaves broadest at or near the middle, variously lobed or toothed, not abruptly
contracted toward the base.
Leaves more or less deeply lobed, the lobes bristle-pointed. Acorns ovoid, bitter.
BLACK or RED OAKS,
Leaves glabrous or with tomentum only in the axils of the veins beneath.
Leaves with asymmetric lobes.

Leaves narrowly oblong or oblanceolate; cup hemispheric or nearly so,
about 15 mm. broad.......2.....-.-c.ccc cee ee eee la. Q. heterophylla,

Leaves of a broader type; cup about 20 mm. broad........... 2a. Q. leana.

Leaves with more or less symmetric lobes.

Average leaves 10 cm. long or less, the basal lobes small, triangular. Cup
saucer-shaped, 10 mm. broad; lowermost branches pendent; leaves
brown in autumn........00000000...0.......-0.2.---. 4. Q. palustris. -

Average leaves 15 cm. long or more, variously Iobed, the sinuses broad.

Lateral lobes of the leaves commonly simple, with few teeth, forming
an angle of 45° with the midrib; cup saucer-shaped, 2.5 em. broad
or more. Leaves red-brown in autumn............. 5. Q, maxima.

Lateral lobes commonly 3-cleft, with accessory teeth, the primary lobes
forming an angle of about 60° with the midrib; cup turbinate or
hemispheric, 2 cm. broad or more.

Buds reddish brown, sparingly pubescent; leaves scarlet in autumn.
6. Q. coccinea.
Buds densely grayish-pubescent; leaves brown in autumn.

8. Q. velutina.
Leaves pubescent or tomentulose beneath.

Average leaves about 7 cm. long, commonly 5-lobed; cup 10 mm, broad,
turbinate. Lobes simple or nearly so, broadly triangular, the basal
ones very short or wanting; acorn globose-ovoid........ 7. Q. ilicifolia,

Average leaves 12 cm. long or more; cup 15 mm. broad or more,turbinate.

Buds densely grayish-pubescent; leaves more or less deeply 7-lobed, the

lateral lobes broad; acorn ovoid; leaves brown in autumn.

8. Q. velutina.

Buds sparingly pubescent, red-brown; leaves more or less deeply 3-13-

lobed, the lobes commonly simple, falcate, the base rounded; acorn

globose-ovoid; leaves scarlet inautumn.................. 9. Q. rubra.

Leaves varying from serrate to deeply lobed, the lobes not bristle-tipped (at
most acute).

Leaves more or less deeply lobed (sometimes toothed in no, 11). Wuirre oaks.

Leaves 20 cm. long or larger, obovate-oblong, more or less deeply 13-15-lobed,
the lobes oblong. Cup hemispheric, 20 mm. broad; acorn oblong; leaves
red-brown in autumn....2 2.2.0... 2.2 e cece eee eee cece eee 10. Q. saulii.

FLORA OF THE DISTRICT OF COLUMBIA. 139

Leaves 12 cm. long or larger, more or less deeply 5-9-lobed.

Lateral lobes of the leaves divaricate, as broad as long, truncate or shallowly
lobed, the basal lobes small. Cup turbinate, about 10 mm. broad;
acorn ovoid; leaves copper or red-brown in autumn. .11. Q. stellata.

Lateral lobes forming an angle of 45° with the midrib, oblong, simple or with

secondary lobes.

Primary lobes of the leaves entire or 9-8-lobed; cup hemispheric, 15-20
mm, broad; acorn oblong, 2-3 cm. long, stalked. Leaves copper-
brown in autumn; bark of trunk flaky.......-------+- 12. Q. alba.

Primary lobes commonly entire, the leaves smaller; cup 10 mm. broad or
more; acorn sessile or nearly so, ovoid. (Bark and fruit resembling
those of Q. stellata and the leaves those of Q. alba.)

12a, Q. albaXstellata.
Leaves almost regularly toothed.

Leaves angularly toothed or lobed, obovate, 10 cm. long or larger, cuneate at
the base, tomentulose or green and glabrate. Fruit long-stalked: cup
hemispheric, 10 mm. broad or more; acorn ovoid-oblong; bark of trunk
flaky. ....ce. eee eee eee eee eee eee eee eee ee eee ereces 13, Q. bicolor.

Leaves crenate-serrate. CHESTNUT OAKS.

Teeth of leaves blunt.

Fruit sessile; small shrub. Leaves obovate, 10 cm. long or less, pale and
pubescent beneath, copper-red in autumn; cup hemispheric, 15
mm. broad or less; acorn ovoid.........---------- 14, Q. prinoides.

Fruit stalked; tall trees.

Leaves oblong or obovate, pale beneath, 15 cm. long or larger, reddish
brown in autumn; cup turbinate, about 20 mm. broad; acorn
ovoid or oblong, 15-24 mm. long............-------15. Q. montana.

Leaves obovate, abruptly acuminate, 10 cm. long or larger, pale and
pubescent beneath, brown in autumn; cup hemispheric, 30 mm.

broad or more; acorn OVOId.........-----+-++2e 252 - 16. Q. prinus.
Teeth of leaves acute.
Plants small shrubs.........-.---------eee ee eee eee 14, Q. prinoides.
Plants trees.
Leaves obovate, broad..........---.--.++++-----5000> 16. Q. prinus.

Leaves oblong-lanceolate, gray-tomentulose bencath,. 10 cm. long or
larger. Cup 15 mm, broad or more; acorn ovoid, 12-20 mm. long.
17. @. muhlenbergii.

1. Quercus phellos L. WILLOW OAK.
Moist woods. Eastern U.S.
All the oaks flower in April or May and mature the fruit in September.

la. Quercus heterophylla Michx. f. -. BARTRAM OAK.
With the preceding; rare. (Q. phellos Xvelutina.)
2. Quercus imbricaria Michx. SHINGLE OAK.

Low woods. Eastern U.S.

2a. Quercus leana Nutt.
With the preceding; rare. (Q. imbricariaX velutina.)
3. Quercus marilandica Muenchh. BLACK JACK. JACK OAK.
Dry soil. Eastern U.S. (Q. nigra of Ward’s Flora.)
The characteristic form on the Serpentine barrens has 5-lobed rather than 3-lobed,
leaves. (Q. nigra quinqueloba A. DC.)

4, Quercus palustris DuRoi. PIN OAK.
Low places. Northern states, south to Va.
Frequently planted in parks and along streets. A tree is shown in plate 22A.

140 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

5. Quercus maxima (Marsh.) Ashe. RED OAK.
Low woods. Eastern N. Amer. (Q. rubra maxima Marsh.: Q. rubra of authors, not L.)
A tree is shown in plate 22B.

6. Quercus coccinea Wang. SCARLET OAK.
Dry woods and hillsides. Northern states, south to N. C.
7. Quercus ilicifolia Wang. BEAR OAK.

Dry ground; near Laurel, possibly not reaching our limits. Northern states, south
to Md. (Q. nana Sarg.)

8. Quercus velutina Lam. BLACK OAK. QUERCITRON.
Dry woods. Eastern U.S. (Q. tinctoria Michx.)
9. Quercus rubra L. SPANISIL OAK,

Dry woods, Southern states, north toN.J. (Q. falcata Michx.; Q. triloba Michx.;
Q. digitata Sudw.)

10. Quercus saulii C. Schneid. SAUL’S OAK.

Dry woods; frequent in Q. alba and Q. montana colonies. (Q. prinusXalba of
authors; @Q. montanaX alba?)

(Quercus macrocarpa Michx., the bur oak; is sometimes planted within our limits.
Native farther north and west, Readily recognized by its lyrate-pinnatifid, obovate
or obovate-oblong leaves, 20 cm. long or more; cup hemispheric, 3-5 em. broad, the
upper scales produced into filiform tips; acorns depressed-globose, haif covered by
the cup.

11. Quercus stellata Wang. Post OAK.
Dry woods and barrens. Eastern U. 8. (Q. minor Sarg.)
12. Quercus alba L. . WHITE OAK.

Dry woods. Eastern U.S.
A tree is shown in plate 23.
12a. Quercus alba & stellata?
Dry woods, with Q. alba and Q, stellata; perhaps a distinct species.
13. Quercus bicolor Willd. SWAMP WHITE OAK,
Low woods and river bottoms. Eastern N. Amer. (Q. platanoides Sudw. )
The leaves on young growth of this species much resemble those of Q. lyrata,

14. Quercus prinoides Willd. SCRUB CHESTNUT OAK,
Dry grounds and pine barrens. Eastern U. §,

15. Quercus montana Willd. Rock CHESTNUT OAK.
Dry woods and hillsides, Eastern U.S. (Q. prinus of authors, not L.)

16, Quercus prinus L. BASKET OAK.

Low woods and swampy ground, Southern states, north to Del. (Q. michausiti
Nutt.)
17. Quercus muhlenbergii Engelm. ; CHESTNUT OAK.
Low places. Eastern U. 8. (Q. acuminata Sarg.)

39. ULMACEAE. Elm Family.

Leaves of an oval type, narrowed to an unequal base; fruit a winged nut (samara),
1. ULMUS.
Leaves of an ovate type, with a broad rounded unequal base; fruit a drupe.
| 2. CELTIS.
1. ULMUS L. Eto.

Leaves glabrous or nearly so on the upper surface; wing of the samara ciliate, the
body glabrous. ............00..20 0000 eee cece eee eee eee eeee 1. U. americana.
Leaves very rough on the upper surface; wing of samara not ciliate, the body pubes-
CONE. oe eee ween ence ee ee cece eee eeeeeeeee 2. U. fulva.

FLORA OF THE DISTRICT OF COLUMBIA. 141

1. Ulmus americana L. AMERICAN ELM.
Low woods and along streams; also planted along our streets. March; fr. Apr.

Eastern U.S.

2. Ulmus fulva Michx. RED ELM.
Low woods and along streams; also in cultivation. March; fr.Apr. Eastern U.S.
Known also as slippery elm.

Ulmus campestris L. the English elm, from western Europe, is frequently planted.
Petioles 5 mm. long or more; blades 5-7.5 cm, long, oval or ovate, short-acuminate,
scabrous above, pubescent beneath; fruit nearly orbicular, 10 mm. broad or more,
the seed touching the notch.

2. CELTIS L. HackBeErry.

Leaves mostly entire, ovate-lanceolate, acuminate, 6 cm. long and 4 cm. wide or

smaller, glabrous on the upper surface....-...-.-----+---- 1. C. mississippiensis.
Leaves serrate, of a broader type, mostly acute.

Leaves glabrous or nearly so on the upper surface........------- 2. C. occidentalis.

Leaves rough on the upper surface........---------2++++++eeeeeee 3. C. crassifolia.

1. Celtis mississippiensis Bosc.

Near Anacostia (Painter), Southern states, north to Va.
2. Celtis occidentalis L.

Rocky soil and dry woods. May; fr. Sept-Oct. Northern states, south to N. C.
8. Celtis crassifolia Lam.

Potomac Valley above Georgetown. May; fr. Sept.—Oct. Northern states, south

to 8. C.
40, MORACEAE, Mulberry Family.

Ficus carica L., the common fig, is often found in waste ground, especially about
Alexandria.

Leaves entire, ovate to oblong-lanceolate, acuminate; staminate flowers in long-
stalked racemes, Pistillate flowers in globose heads; fruit yellowish green, 10
cm. in diameter or less... ...-...-. 2202-222 cece ee eee eects 1. TOXYLON.

Leaves toothed or lobed; staminate flowers in spikes.

Twigs hirsute; fruit in globose heads 2 cm. in diameter, not edible, on short stout
peduncles. Leaves rough above, velvety beneath, ovate-lanceolate, serrate

or 2-3-lobed .......------ ee eee eee ee ee eee eet e nen e re reeees 2. PAPYRIUS.

Twigs glabrous or pubescent; fruit aggregate, oblong, edible........---- 3.MORUS.
1. TOXYLON Raf.

1. Toxylon pomiferum Raf. OSAGE ORANGE.

Escaped from cultivation, May. Native farther west. (Maclura aurantiaca

Nutt.; M. pomifera ©. Schneid.)
2. PAPYRIUS Lam.

1. Papyrius papyrifera (L.) Kuntze. PAPER MULBERRY.

Escaped from cultivation; forming thickets. May. Native of the Pacific Islands.
(Broussonetia papyrifera Vent.)

“ 3. MORUS L. MuLBERRY.

Leaves cordate-ovate, smooth, glabrous or nearly so; fruit white, 1-1.5 cm. long.

1. M. alba.

Leaves obliquely ovate, rough above, pubescent beneath; fruit purple, 2 cm. long

OF NOLO... ee ee ee eee eee eee eee teen rer eneee 2. M. rubra.

1. Morus alba L. WHITE MULBERRY.
Escaped from cultivation. May. Native of western Asia and Eur,

2. Morus rubra L. RED MULBERRY.

Low woods. May. Eastern U.S.

142 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

41, URTICACEAE, Nettle Family.

Leaves lobed or divided. Plants without stinging hairs,
Plants erect annuals; leaves divided to the base into several leaflets.
, 1, CANNABIS.
Plants twining perennials; leaves toothed or merely lobed, not divided to the base.

2. HUMULUS.
Leaves merely toothed.

Leaves alternate.
Plants without stinging hairs; leaves lanceolate, less than 2.5 cm. wide; flower

clusters sessile in the axils of the leaves................... 8. PARIETARIA.
Plants with stinging hairs; leaves broadly ovate, 5-12 cm, wide or wider; flowers in
loose branched cymes....................00---22-000- 4, URTICASTRUM.
Leaves opposite.
Plants with stinging hairs, perennial............................--. 5. URTICA.

Plants without stinging hairs, minutely hairy or glabrous.
Plants annual, glabrous; leaves shining, succulent, the petioles usually as long
as the blades; flowers in loose cymes................0--202---- 6. PILEA.
Plants perennial, more or less hairy; leaves not shining, thin, the petioles
shorter than the blades; flowers in spikes or loose cymes..7. BOEHMERIA.

1. CANNABIS L.
1, Cannabis sativa L. Heme.
Occasional in waste ground about Washington. June-Aug. Native of Eurasia;
common in cultivation and often escaping.

; 2. HUMULUS L. Hor.

1. Humulus lupulus L. COMMON HOP.

Rare as an escape from cultivation. Aug.-Sept. Native of Eur.; often cultivated in
the U.S. for ornament or for its bracts, which are used in making yeast, and frequently
escaping:

Humulus japonicus Sieb. & Zuce., the Japanese hop, was collected in waste ground
along the Washington river front, Sept., 1899 (Steele). Native of Japan; often culti-
vated for ornament, and escaped at various places in the U. 8.

3. PARIETARIA L.

1. Parietaria pennsylvanica Muhl. PELLITORY.
Rich woods or along stone walls; rare. June-July. Widely distributed in N.
Amer.
4. URTICASTRUM [F abr.
1. Urticastrum divaricatum (L.) Kuntze. Woop NETTLE.
Rich woods and alluvial soil; common. July-Oct. Eastern N. Amer. (Laportea
canadensis Gaud. )
5. URTICA L. Nerrte.
Leaves lanceolate or ovate-lanceolate, usually twice as long as broad or longer, rounded
or cordate at the base, evenly toothed with comparatively small teeth, only

slightly bristly beneath......... 0.0.02 eee eee 1. U. gracilis.
Leaves ovate or broadly ovate, usually less than twice as long as broad, coarsely and
often irregularly toothed, very bristly beneath......................2. U. dioica,

1. Urtica gracilis Ait.

Wet soil, especially on canal banks, there abundant. June-Aug. Widely dis-
tributed in N. Amer.
2. Urtica dioica L.

Moist soil; frequent. May-July. Native of Eur.; naturalized in the eastern U.S.

FLORA OF THE DISTRICT OF COLUMBIA. 143

6. PILEA Lindl.

1. Pilea pumila (L.) A. Gray. RICHWEED.
Moist, often alluvial soil; common. Aug.—Sept. Eastern N. Amer, (Adicea
pumila Raf.)
7. BOEHMERIA Jacq.

1. Boehmeria cylindrica (L.) Swartz. FALSE NETTLE.
Moist or wet soil; frequent. July-Oct. Eastern N, Amer,
Boehmeria nivea (L.) Gaud,, ramie, with leaves white-hairy beneath, was collected
in waste ground along the river front, Washington, Sept., 1899 (Steele). Native of
Asia; sometimes cultivated for ornament or for its fiber, rarely escaping in the U. 8.

42, LORANTHACEAE. Mistletoe Family.
1. PHORADENDRON Nutt.

1. Phoradendron flavescens (Pursh) Nutt. MISTLETOE.

Rare in our region but more abundant eastward toward Chesapeake Bay, growing
on branches of Nyssa sylvatica and Acer rubrum. May-July, the white berries matur-
ing in late autumn, Southern states, north to N. J.

43, SANTALACEAE, Sandalwood Family.
" 1, COMANDRA Nutt.

1. Comandra umbellata (L.) Nutt. BASTARD TOAD-FLAX.
Dry fields and woods; frequent. May-July. Eastern N. Amer.
The plant is parasitic upon the roots of other plants. It is glabrous, more or less
glaucous, with oblong or elliptic, sessile, alternate, obtuse or acutish leaves, and
small white flowers in cymes.

44, ARISTOLOCHIACEAE. Birthwort Family.

Stems erect, slender; petioles shorter than the leaf blades, these ovate or ovate-
oblong, long-tapering at the tip; flowers very irregular... .. 1. ARISTOLOCHIA.
Stems prostrate, stout, rooting; petioles longer than the blades, these kidney-shaped,
broadly rounded at the apex; flowers regular...........-.-...--.- 2. ASARUM.

1. ARISTOLOCHIA L.

1. Aristolochia serpentaria L. VIRGINIA SNAKEROOT.
Dry woods; local. June-July. Eastern U. 8.
The deep purple flowers are borne on slender scaly branches at the base of the
plant. The roots are used in medicine.

2. ASARUM L.

1, Asarum canadense L. WILD GINGER.

Rich woods; common. Apr.—May. Eastern N. Amer.

The rootstocks have the flavor of ginger.

Material from our region has been referred to A. reflerwm Bicknell (A. canadense
reflecum Robinson; A. reflerum ambiguum Bicknell). That is supposed to differ from
A, canadense in having short calyx lobes about as long as the calyx tube; in A. canadense
the calyx lobes are longer than the tube. A. reflerwm, however, scarcely seems worthy
of specific rank.

144 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

45. POLYGONACEAE. Buckwheat Family.

Sepals 6, the 3 outer ones unchanged in fruit, the 3 inner ones mostly developed into
WINGS... 2.22. e eee ee eee eee eee eect eeeeee 1. RUMEX.
Sepals usually 4 or 5, those of the outer row often reflexed or enlarged at maturity.
Flowers axillary, solitary or clustered; leaf blades jointed at the base; stipule
sheaths (ocrez) 2-lobed or laciniate...........2..---2-+------ 2. POLYGONUM.
Flowers in terminal or axillary, spikelike, often panicled racemes; blades not
jointed; ocrez not lobed or laciniate.
Ocrex cylindric, truncate.
Calyx curved; sepals 4; stamens 4.............0....00022220005- 3. TOVARA,

Calyx not curved; sepals mostly 5, if fewer the stamens more than 5.
4. PERSICARIA,

Ocrez oblique, more or less open toward the leaf.
Flowers with the outer sepals keeled or conspicuously winged at maturity.
Plants twining vines; ocrese persistent.........-...2---- 5. BILDERDYKIA.

Plants very tall stout herbs, woody below; ocreg fugacious.
6. PLEUROPTERUS.

Flowers with none of the sepals keeled or winged.
Stems ascending or reclining, armed with very numerous recurved prickles;
ocrese persistent.........2.. 002. eee eee eee eee eee eee 7. TRACAULON,

Stems erect, unarmed; ocrev fragile, soon withering ......8. FAGOPYRUM.
1. RUMEX L. Dock.

Plants small, with slender creeping propagating roots; foliage strongly acid; leaves

hastately lobed........2 2222.2... eee cee ene 1. R. acetosella.
Plants large; rootstocks stout, deep-seated; foliage slightly or not at all acid; leaves
not lobed.

Leaves flat, bright or pale green.
Pedicels several times as long as the wings; each of the 3 wings usually bearing a
well-developed tubercle at maturity................------ 2. R. verticillatus.
Pedicels about equaling the wings; usually only one of the wings tuberculate.
3. R. altissimus.
Leaves wavy or crisped at the margins, dark green.
Wings with a few spreading bristle-like teeth................. 4. R. obtusifolius.
Wings entire or nearly so.
Blades of lower leaves narrowed at base; usually only one of the wings tuber-

culate... 2.2... eee eee eee eee 5. R. patientia.

Blades of lower leaves cordate or obtuse at base; all 3 of the wings usually
tuberculate... 2... 2. cee ee eee ee eee eee 6. R. crispus.

1. Rumex acetosella L. SHEEP SORREL.

Dry fields and rocky hillsides; abundant. Summer. Nearly throughout N. Amer.;
naturalized from Eur. .
2. Rumex verticillatus L. SWAMP DOCK.
Swamps and moist alluvial situations; several localities, principally along the upper
Potomac. May-July. astern N. Amer.
3, Rumex altissimus Wood,
Moist alluvial situations; not uncommon, especially along the Potomac. Apr.-
June. Eastern U.S.

4, Rumex obtusifolius L. BITTER DOCK
Waste places; common. Summer. Nearly throughout N. Amer.; naturalized from

Eur.

FLORA OF THE DISTRICT OF COLUMBIA. _ 145

5. Rumerx patientia L.
Dumps and waste places; apparently not very common. May-June. North-
eastern states westward; naturalized from Eur.
6. Rumex crispus L. NARROW DOCK.
Roadsides and waste places; common. Summer. Naturalized from Eur., nearly
throughout N. Amer.
Hybrids between this species and R. obtusifolius are reported by Ward.

2, POLYGONUM L. KwNotTweep.

Stem and branches angled.
Leaves plicate; fruits erect, on stout pedicels...... cence eee eee cece eee 5. P, tenue.
Leaves flat, the margins merely revolute; fruits drooping on slender reflexed pedicels.
6. P. douglasii.
Stem and branches terete or nearly so, usually striate.
Plants chiefly prostrate, the branches mostly basal; flowers comparatively small,
the sepals less than 2 mm. long.

Leaves usually acute; achene ovoid, acute...........---++------ 1. P., aviculare.
Leaves obtuse or subacute; achene broadly ovoid, constricted below the apex,
often conspicuously 80.........---.------- eee eee ee ee eee 2. P; buxiforme.

Plants erect or ascending, more or less diffusely branched above the base; flowers
larger, the sepals 2-3 mm. long.
Leaves elliptic to obovate, obtuse to acutish, yellowish green,.... 3. P. erectum.
Leaves linear-elliptic to lance-elliptic, acuminate, green (not yellowish).
4, P. atlanticum.

1. Polygonum aviculare L. KNOTGRASS.

Cultivated and waste places; a common weed. Summer and autumn. N. Amer.
and Eur.
2. Polygonum buxiforme Small.

Waste ground; apparently rare locally, a single record. July. Widely distributed
in N. Amer. °
8. Polygonum erectum L,

Moist or dry situations; common. July-Sept. Widely distributed in N. Amer.
4, Polygonum atlanticum (Robinson) Bicknell.

Vicinity of Government fish ponds, a single record (July, 1902). Adventive; native
of salt marshes along the N. Eng. coast.
5. Polygonum tenue Michx.

Dryish, more or less sandy slopes; not very common. July-Sept. Eastern N. Amer.
6. Polygonum douglasii Greene.

Old circus grounds; a single record (Aug. 7, 1912). Western U. S.; adventive east-
ward.

3. TOVARA Adans.

1. Tovara virginica (L.) Raf. JUMPSEED,
Low moist woods and alluvial thickets;common. Latesummer. Eastern N. Amer.

4. PERSICARIA Mill.

Spikes solitary or in pairs.
Plants usually aquatic; leaves floating, long-petioled, obtuse or acutish; spikes ovoid
or oblong, not more than 2.5 cm. long, the peduncles glabrous...1. P. amphibia.
Plants usually of swamps or stream banks, erect or ascending; leaves short-petioled,
acuminate; spikes 3-10 cm. long, the peduncles hispid..2. P. muhlenbergil.

69289—19——10

146 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Spikes several or numerous,
Ocree not fringed with bristles.
Flowers white, greenish, or pink, borne in slender, elongate, usually drooping

spikes 2-8 cm, long.............2.-22-2--- 0-2 eee eee eee 8. P. lapathifolia,
Flowers deep pink or rose-colored, borne in thick oblong-cylindric erect spikes
2-5 em. long. ........ 2.222 ee eee eee eee 4, P. pennsylvanica.

Ocrev fringed with bristles.
Sepals conspicuously gland-dotted.

Spikes drooping; stamens 4 or 6; achene granular and dull..... 5. P. hydropiper.
Spikes erect; stamens 8; achene smooth and shining....... 6. P. punctata.

Sepals not gland-dotted.

Plants up to 2.5 meters high, coarse; ocrese often with a spreading herbaceous
border; leaves long-petioled, the blades broad, ovate or oblong; spikes
drooping.........2-.-.-.. 222. eee eee cee ee eee ees 7. P. orientalis.

Plants 20-100 cm. high; ocrex without a spreading border; leaves sessile or nearly
so, the blades narrow, linear-lanceolate to oblong-lanceolate; spikes erect.

Plants annual; spikes short-cylindric, dense. Leaves usually with a dark

triangular or crescent-shaped spot near the middle....... 8. P. mitis.
Plants perennial; spikes slender, often interrupted... .. 9. P. hydropiperoides.
1. Persicaria amphibia (L.) 8. F. Gray. WILLOW-WEED.

Aquatic; two collections on the Potomac flats between the Outlet Lock and Fad’s
Mill. Midsummer. Widely. distributed in N. Amer. (Polygonum hartwrightti A.
Gray; P. amphibium L.)

2. Persicaria muhlenbergii (S. Wats.) Small.

River banks and other moist situations; not uncommon. Aug.-Sept. Widely
distributed in N. Amer. (Polygonum emersum Britton; P. amphibium terrestre of
Ward’s Flora; P. muhlenbergit 8. Wats.)

3. Persicaria lapathifolia (L.) 8. F. Gray. WILLOW-WEED,

Low waste places; common, especially on the Potomac Flats. July—Sept. Through-
out N. Amer. (Polygonum incarnatum Ell.; P. lapathifolium L.)

4. Persicaria pennsylvanica (L.) Small.

Wet places generally; common. July-Sept. Eastern N. Amer. (Polygonum
pennsylvanicum LL.)

5. Persicaria hydropiper (L.) Opiz. SMARTWEED.

Low moist situations; locally common. July-Sept. Nearly throughout N. Amer.;
naturalized from Eur. (Polygonum hydropiper L.)

6. Persicaria punctata (H1l.) Small. ; SMARTWEED.

Swamps and moist alluvial situations; common. July-Sept. Nearly throughout
N. Amer. (Polygonum punctatum Ell.)

7. Persicaria orientalis (L.) Spach. PRINCE’S-FEATHER.

Waste places; not uncommon, particularly along the Canal and on the Potomac
Flats. July-Sept. Native of India; escaped from gardens and naturalized in the
eastern U.S. (Polygonum orientale L.) . ‘
8. Persicaria mitis Gilib. Lapy’s-THUMB. PINKWEED.

Moist waste places; common, especially along the river. June-Sept. N. Amer.
and Eur. (Polygonum persicaria L.; Persicaria persicaria Small.)

9. Persicaria hydropiperoides (Michx.) Small.

Wet alluvial situations; several stations along the Potomac, but not common.

Aug.-Oct. N. Amer. (Polygonum hydropiperoides Michx.)

5. BILDERDYEKIA Dum.

Plants annual; outer sepals keeled at maturity............---- 1. B. convolvulus.
Plants perennial; outer sepals conspicuously winged at maturity...2. B. scandens.

FLORA OF THE DISTRICT OF COLUMBIA. 147

1. Bilderdykia convolvulus (L.) Dum. ° BINDWEED.

Waste and cultivated ground; common weed. Summer. Naturalized from Eur. ;
nearly throughout N. Amer. (Polygonum convolvulus L.; Tiniaria convolvulus
Webb & Moq.)
2. Bilderdykia scandens (L.) Greene.

Thickets and brushy fields; abundant. July-Sept. Eastern N. Amer. (Poly-
gonum scandens L.; Tiniaria scandens Small.)

Polygonum cristatum Engelm. & Gray is a form of this species with incised sepal
wings. It has been collected at several localities within our range.

6. PLEUROPTERUS Turcz.

1. Pleuropterus zuccarinii Small. JAPANESE KNOTWEED,
Escaped from cultivation at several localities. July-Oct. Native of Japan; escaped
locally in the northeastern U.S. (Polygonum cuspidatum Sieb. & Zucc.)

7. TRACAULON Raf. TEAR-THUMB.
Stems sharply 4-angled; leaves short-petioled, the blades arrow-shaped; style 3-

parted; achene sharply 3-angled...................-2.------ 1. T. sagittatum.
Stems ridged; leaves mostly long-petioled, the blades halberd-shaped; style 2-parted;
achene lenticular.......... 2.2... eee eee eee eee 2. T. arifolium.

1. Tracaulon sagittatum (L.) Small.

Swamps, wet thickets, and stream banks; common. Aug.Sept. Fastern N.
Amer. (Polygonum sagittatum L.)
2. Tracaulon arifolium (L.) Raf.

Low woods or borders of woods; not very common. Aug.-Sept. Wastern N,
Amer. (Polygonum arifolium L.)

8. FAGOPYRUM Gaertn. BuckwHEAtT.

1. Fagopyrum esculentum Moench.
Dumps and waste places; occasional. Summer. Cultivated in N. Amer.;
sometimes escaping. (Fugopyrum fagopyrum Karst.)

46. CHENOPODIACEAE. Goosefoot Family.

Leaves linear, pungent-tipped; plants neither mealy nor glandular. ...- 8. SALSOLA.
Leaves broader than linear, not pungent-tipped; plants glandular or more or less
white-mealy.
Fruit inclosed in a regular toothed calyx; leaves all alternate; flowers all alike.
1. CHENOPODIUM.
Fruit inclosed by 2 nearly distinct triangular green bracts; lower leaves opposite;
flowers of 2 kinds, staminate and pistillate............-..-2....-- 2. ATRIPLEX.

1. CHENOPODIUM L.

Plants with a strong disagreeable odor, even when dry, more or less glandular; leaves
bright green; flower clusters in slender spikes.........-. ..1. C. ambrosioides.
Plants without a strong odor, never glandular; flower clusters not in slender spikes.

Outer coat of the fruit easily separated from the seed, the latter shining; plants
slender, ustially found in woods. Leaves bright green, thin, entire or toothed

near the base........2.2--.-2.02 22-22 e eee eee eee eee eee 2. C. boscianum.
Outer coat of the fruit firmly attached to the seed and not easily separated from it
by rubbing; plants usually stout and frequenting waste or cultivated ground.
Inflorescence usually shorter than the leaves, comparatively few-flowered; leaves
green, not at all mealy, shining on the upper surface.......... 8. C, murale |

148 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Inflorescence usually much longer than the leaves, many-flowered; leaves never
shining, at least the youngest ones more or less white-mealy.

Leaves bright green, slightly mealy when young; seeds 1.5-2 mm. broad.

; 4. C. paganum.

Leaves white-mealy; seeds 1.5 mm. broad or smaller...........-. 5. C. album.

1, Chenopodium ambrosioides L. WorMSEED,

Waste ground, especially along streets and about barnyards; common. July—Oct.
Widely distributed in N. Amer. and in the tropics of the Old World. (C. anthelminti-
cum L.; C. ambrosioides anthelminticum A. Gray.)

The seeds, “ American wormseed,’’ are used medicinally.

Chenopodium botrys L., Jerusalem oak, with sweet-scented leaves, was reported
from Washington by Ward, but has not been collected recently.

2. Chenopodium boscianum Moq.
Woods; infrequent. June-Oct. Eastern U.S.

2. Chenopodium murale L. NETTLE-LEAF GOOSEFOOT.
Common along streets. July-Oct. Native of Eur.; now widely dispersed in
most civilized regions.
C. urbicum of Ward’s Flora doubtless belongs here; the latter species is not known
from our region.

4, Chenopodium paganum Reichenb.

Moist ground; common. June-Oct. Native of Eur.; now widely naturalized in
the U.S. (C. viride of most authors, not of Linnaeus.)

Specimens of this were once reported from the District by Steele as C. rubrum
L., a quite different species that is not known to occur here. C. lanceolatum Muhl.
is a form, or perhaps a species, with narrow leaves.

5. Chenopodium album L. Lamp’s-QUARTERS. PIGWEED.

Waste and cultivated ground; an abundant weed. June-Oct. Native of Eur.
but now widely naturalized in N. Amer., or it may be in part native.

The young plants are used as “greens.”

2, ATRIPLEX L.

1, Atriplex hastata L.

Common in the streets of Alexandria; rare in waste ground about Washington.
July-Oct. Widely dispersed in the U. 8.; our plants probably adventive from Eur.
(A. patula hastata A. Gray.)

3. SALSOLA L.
1. Salsola kali L. SALTWORT.
Reported from Alexandria by Ward. Trequent along the Atlantic coast of N. Amer.
and in Kur.

47, AMARANTHACEAE, Amaranth Family.

Leaves opposite; flowers white; plants perennial..............-.------- 1, IRESINE.
Leaves alternate; flowers green or reddish; plants annual.

Fruit fleshy, 3-5-angled, indehiscent; pistillate flowers without sepals; plants

pistillate and staminate; leaves lanceolate........--.--.--------+- 2. ACNIDA.

Fruit thin and dry, not angled, dehiscent; pistillate flowers with sepals; pistillate

and staminate flowers on the same plant; leaves usually broader than lanceolate.

3. AMARANTHUS.

FLORA OF THE DISTRICT OF COLUMBIA. 149

1, IRESINE P. Br.

1. Iresine rhizomatosa Standley.

Known within our region only from Plummers Island, the type locality. South-
eastern U.S.

The species has usually been confused with I. celosia L. (I. paniculata Kuntze; I.
celosioides L.)

2. ACNIDA L.

1. Acnida cannabina L. WATER HEMP.

Waste or swampy ground along the Potomac about Washington and Alexandria;
rare. Aug.-Oct. N. H. to N.C.

8. AMARANTHUS L.

Plants with long stout spines in the Jeaf axils...................2--.. 1. A. spinosus.
Plants without spines.
Flower clusters all in the axils of the leaves, mostly shorter than the petioles.
Plants erect; seed about 0.8 mm. broad; bracts much longer than the sepals,

with long slender tips..............2..-222.2.-.20-0- 2020-05 2. A. graecizans.
Plants prostrate; seed about 1.5 mm. broad; bracts about as long as the sepals,
with short tips..........-..2.22-22 22-2 eee 3. A. blitoides.
_Flower clusters in long spikes arranged in panicles.
Flowers bright purplish red; sepals shorter than the fruit......... 4, A. cruentus.

Flowers green or the spikes slightly tinged with red; sepals equaling or longer
than the fruit.
Sepals acute, the flower spikes slender, green or yellowish green; plants gla-

brous or nearly 80........ 2.0... ee eee eee eee eee ee eee 5. A. hybridus.

Sepals very obtuse, often notched at the apex, the spikes very stout, whitish;
plants very hairy about the inflorescence................ 6. A. retroflexus.

1. Amaranthus spinosus L. SPINY AMARANTH.

Waste and cultivated ground. July-Oct. Native of tropical Amer.; widely
naturalized in the eastern U. S.
2. Amaranthus graecizans L. TUMBLEWEED.
Waste and cultivated ground. July-Oct. Throughout the U. 8. and southern
Canada. (A. albus L.)
3. Amaranthus blitoides S. Wats.
Waste ground, especially along railroads; rare. Native of the southwestern U. 8.
but now adventive in many places eastward.
4, Amaranthus cruentus L.
Waste ground; infrequent. Native habitat not known but probably tropical
Amer., the plant sometimes cultivated and escaping. (A. paniculatus L.)
5, Amaranthus hybridus L. COMMON AMARANTH OF PIGWEED.
An abundant weed in waste and cultivated ground. July—Oct. Widely dispersed
in N. Amer., adventive northward. (A. retroflecus of Ward’s Flora.)
6. Amaranthus retroflexus L.
Waste and cultivated ground; infrequent. July—Oct. Nearly throughout the U.
S. and southern Can.

48, ALLIONIACEAE. Four-o’clock Family.
1. ALLIONIA L.

1. Allionia nyctaginea Michx. UMBRELLAWORT.

Along the railway embankment at Chevy Chase Lake, well established, May, 1916
(Maxon & Siandley). Native of the western U. 5.; often adventive eastward. (Oxyb
aphus nyctugineus Sweet.)

150 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

49, PHYTOLACCACEAE. Pokeweed Family.
1. PHYTOLACCA L.

1. Phytolacca americana L. POKEWEED.
Common in rich moist soil or waste ground. June-Sept. Eastern U. 5. (P.
decandra L.)
The young shoots are used as ‘‘greens,” and are seen abundantly in Washington
markets. The roots are used medicinally.

50. AIZOACEAE. Carpetweed Family.

1. MOLLUGO L.
1. Mollugo verticillata L. . CARPETWEED.
Sandy fields or waste ground; common. July-Sept. U.S. and Mex.

51. PORTULACACEAE. Purslane Family.

Leaves all clustered at the base of the stem, the blades terete. Plants perennial;

petals rose-colored; capsule opening by 3 valves.........-..---- 1, TALINUM,

Leaves not all clustered at the base of the stem, each stem bearing 2 or numerous

leaves, the blades flat or terete.

Leaves numerous on each stem; annuals with terete or wedge-shaped leaves; petals
usually yellow or red; flowers axillary; capsule opening by a lid.

2. PORTULACA,

Leaves 2 on each stem; perennials with tuberous roots,the leaves nearly linear,

flat; petals pink; flowers in loose terminal racemes: capsule opening by

3 valves ...---- 2-2 eee eee eee eee eee eee eee 3. CLAYTONIA.

1. TALINUM Adans.

1. Talinum teretifolium Pursh. FAME FLOWER.
Reported by Holm from a ‘‘dry moorland beyond Silver Hill.’’ Eastern U.S.

2. PORTULACA L.
1, Portulaca oleracea L. PURSLANE.
Common weed in cultivated ground. Flowering throughoutthesummer. U.S. and
tropical Amer.
The plants are often cooked as ‘‘greens.”
Portulaca grandiflora Hook., with flowers 2-3 cm. wide and terete leaves, is common
in cultivation, and is sometimes found asa waif in waste ground.

3. CLAYTONIA L,
1. Claytonia virginica L. SPRING BEAUTY.
Moist woods; common. March-May. Eastern N. Amer.
The flowers are shown in plate 17A.

52. CORRIGIOLACEAE. Whitlow-wort Family.

Leaves elliptic or oblong. Plants annual; stipules present; sepals not awned.
1. ANYCHIA.,
Leaves narrowly linear.
Sepals tipped with short spinelike awns; stipules present, white and scaricus;
plants perennial.............-----2 2-0 - eee eee eee eee eee ee 2, PARONYCHIA.
Sepals not awned; stipules wanting; plantsannual............ 3. SCLERANTHUS.

FLORA OF THE DISTRICT OF COLUMBIA. 151

1. ANYCHIA Michx. ForkKED CHICKWEED.

Plants finely hairy, rather stout, the stems with short joints, usually low and spreading;

flowers nearly sessile.............-.------- 0220-22-22 ee ee 1. A. polygonoides.
Plants glabrous, very slender, the stems with long joints, erect; flowers on conspicu-
ous pedicels........-222-.-.220-- eee eee eee ee Lecce eee ee eeeee 2. A. canadensis.

1. Anychia polygonoides Raf.
Dry hillsides; frequent. July-Sept. Eastern U. 8S. (A. dichotoma of some
authors, not of Michaux.)

2. Anychia canadensis (L.) B. 8. P.
Dry woods; frequent. July-Sept. Eastern U.S. (A. dichotoma capillacea Torr.)

2. PARONYCHIA Adans.

1, Paronychia dichotoma (L.) Nutt. WHITLOW-WoRT.
On rocks at Little Falls and Great Falls. July-Oct. Md. to Tex.

8. SCLERANTHUS L.

1. Scleranthus annuus L. KNAWEL.
Easbys Point, north of Old Observatory; Ammendale. May. Native of Eur.;
frequently adventive in N. Amer.

53. ALSINACEAE. Chickweed Family.

Plants with ‘scarious stipules; leaves sometimes whorled, linear; petals sometimes

pink.
Leaves opposite; petals pink; styles 3....... cece cece eee cece eee eens 1. TISSA.
Leaves whorled; petals white; styles5..............2.--0-000 eee 2. SPERGULA.

Plants without stipules; leaves never whorled; petals white or wanting.

Capsule usually twice as long as the calyx or longer, cylindric, slightly curved,
opening at the apex by 10 minute teeth; plants usually with viscid pubescence.
Petals deeply cleft, orrarely wanting. ..............-....2--- 3, CERASTIUM.

Capsule less than twice as long as the calyx, ovoid or oblong, not curved, opening
by 6 or fewer valves; plants without viscid pubescence.

Petals deeply 2-cleft........0.0 00... cece ee cee eee ee eee eee eee eens 4. ALSINE.
Petals entire, or sometimes wanting.
Leaves ovate; sepals acute; styles fewer than the sepals. ..... 5. ARENARIA.
Leaves narrowly linear; sepals obtuse; styles as many as the sepals.
6. SAGINA.

1. TISSA Adans.
1, Tissa rubra (L.) Britton. SAND SPURRY.
Occasional in waste ground and along roadsides. Apr.—July. Widely distributed
in the U. S.; perhaps native in some parts of N. Amer., but largely adventive from
Eur. and Asia. (Spergularia rubra Presl; Lepigonum rubrum Fries.)

2. SPERGULA L.
1. Spergula arvensis L. SpurryY.
Waste ground; Washington and Ammendale. June-July. Native of Eur.; widely
naturalized in N. Amer,
One of our specimens is a very viscid plant with conspicuously margined seeds,
suggesting S. sativa Boenn. The seeds, however, are papillose, as in S. arvensis.
The differences between the two species do not seem very constant,

3. CERASTIUM L.

Petals more than twice as long as the sepals. Plants perennial; pedicels usually
lower than the calyx: capsule about twice as long as the sepals. .1. C, velutinum.

152 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Petals shorter than or but slightly exceeding the sepals.

Inflorescence dense, the pedicels all or nearly all much shorter than the calyx.
Plants annual; leaves elliptic to broadly oval, obtuse or rounded at the apex;
petals shorter than the calyx; capsule about twice as long as the sepals.

2. C, viscosum,

Inflorescence loose and open, at least in age, the pedicels longer than the calyx.

Pedicels several times as long as the calyx; capsule about 3 times as long as the
sepals; plants annual; leaves linear-oblong, acute or acuminate; petals
slightly longer than the calyx.................. ..8. C. longipedunculatum.

Pedicels twice as long as the calyx or shorter; capsule not more than twice as
long as the sepals; plants perennial; leaves oblong to oval, usually obtuse;
petals about equaling the calyx............--.2------------ 4. C. vulgatum.

1. Cerastium velutinum Raf. CHICKWEED.
Common in open rocky places along the Potomac. Apr.-May. Northern states,
south to Va. (C. oblongifolium Torr.)
2. Cerastium viscosum L. MOUSE-EAR CHICKWEED.
Common in wet meadows along the upper Potomac and occasional elsewhere.
Apr.-May. Native of Eur.; widely naturalized in N. Amer.
8. Cerastium longipedunculatum Muhl. NODDING CHICKWEED.
Moist ground, chiefly along the upper Potomac. May. Widely distributed in N.
Amer, (C. nutans Raf.)
4, Cerastium vulgatum L. MOUSE-EAR CHICKWEED.
Wet meadows and waste ground about Washington; Marlboro. Apr.-May. Native
of Eur.; widely naturalized in the U. 8.
Cerastium semidecandrum L., an annual species with smaller leaves, was collected
once by ©. F. Wheeler in the Department of Agriculture grounds. A European spe-
cies, sparingly naturalized from Mass. to Va.

4. ALSINE L.

Stems and leaves glabrous; leaves 1.5-8 mm. wide.
Leaves linear or nearly so, not noticeably broadest at the base; seeds smooth.
1. A. longifolia.
Leaves lanceolate or elliptic, usually broadest below the middle; seeds rough.
2. A. graminea.
Stems and leaves more or less hairy; leaves 440 mm. wide.
Leaves all sessile or nearly so, obtuse or acutish; sepals sparsely hairy or glabrous;
petals longer than the calyx; stamens 10...............00eee eee eee 3. A. pubera.
Leaves petioled, the lower petioles as long as the blades, the blades acute to long-
acuminate; sepals densely hairy; petals shorter than the calyx; stamens 3-7.
4. A. media,

1. Alsine longifolia (Muhl.) Britton. SrIrcHWoRT.
Frequent in damp meadows, Apr.-June. Widely distributed in N. Amer; also in
Eur. and Asia, (Stellaria longifolia Muhl.)
2. Alsine graminea (L.) Britton. STARWORT.
Department of Agriculture grounds and Ammendale. Native of Eur. and Asia;
sparingly adventive in eastern N. Amer. (Stellaria graminea L.)
8. Alsine pubera (Michx.) Britton. STAR CHICKWEED.
Shaded rocks and woods; common. Apr.-May. N. J. to Ind. and Ga. (Stellaria
pubera Michx.)
The plant sometimes flowers in late autumn, specimens having been found in flower
as late as November 10. In late summer the plants send up long vigorous shoots with
very large broad leaves. The flowers are shown in plate 31B.

FLORA OF THE DISTRICT OF COLUMBIA. 153

4. Alsine media L. COMMON CHICKWEED.

Common nearly everywhere in damp ground. Feb.-May. Native of Eur. and Asia;
naturalized nearly throughout N. Amer. (Stellaria media Cyrillo.)

The plants may be found in flower at almost any time during the winter if there are
a few warm days. Stellaria neglecta Weihe (S. media procera Klett & Richter) is a
form with 10 stamens and somewhat crested seeds. It has been reported from our
region by Holm,

Alsine aquatica (L.) Britton, with 5 styles and large leaves, was collected along the
Pennsylvania Railroad, southeast of H Street Bridge, July, 1915 (J. B. S. Norton).
Native of Eur.; sparingly adventive in N. Amer, (Stellaria aquatica Scop.)

5. ARENARIA L.
1. Arenaria serpyllifolia L. SANDWORT.
Common nearly everywhere. Apr.—June. Naturalized from Eur. nearly through-
out eastern N. Amer.
6. SAGINA IL. PEARLWorT.

Parts of the flower in 5’s; seeds orange-brown, resinous-dotted...... 1, S. decumbens.
Parts of the flower in 4’s; seeds dark brown, not resinous-dotted...2. S. procumbens.

1. Sagina decumbens (Ell.) Torr. & Gray.

About Washington; rare. May-June. Eastern U. S. (S. apetala of American
authors. )
2. Sagina procumbens L.

Ammendale (Brother Arsene); brick walk in front of Army Medical Museum
(Maxon & Standley). Apr.-May. Eastern U. 8.

54. SILENACEAE. Pink Family.

Calyx with twice as many ribs or nerves as teeth.
Lobes of the calyx as long as the tube or often much longer; petals much shorter
than the calyx lobes, purple.....................------- 1, AGROSTEMMA,
Lobes of the calyx much shorter than the tube; petals usually much longer than
the calyx lobes, or rarely wanting.
Styles 3 orrarely 4........ wee eee ene eee eee eee eee eee eee eeee 2. SILENE.
Styles 5...... wee eee eee ee eee eee eens 3. LYCHNIS.
Calyx with 5 nerves or ribs, or nerveless, or with very numerous nerves (more than
twice as many as the teeth).
Plants more or less hairy, especially about the flowers; leaves linear; calyx finely

many-nerved, bracted at the base...............-......2.-.-- 4. DIANTHUS.
Plants perfectly glabrous; leaves much broader than linear; calyx not bracted at
the base.
Calyx sharply 5-angled; pedicels usually much longer than the calyx; leaves
sessile and clasping...........-.------------------------- 5. VACCARIA.
Calyx not angled; pedicels much shorter than the calyx; at least the lower
leaves short-petioled ............22-------2-2-----220-5-- 6. SAPONARIA.,

1. AGROSTEMMA L.
1. Agrostemma githago L. CORN COCKLE.
Frequent in fields and waste ground. May-July. Native of Kur. and northern
Asia; naturalized in grain fields nearly throughout the U.S. (Lychnis githago Scop.)
The seeds are poisonous.
2. SILENE L.

Leaves in whorls of 4, ovate-lanceolate, long-acuminate. Stems finely hairy; calyx
inflated; petals white.............-...2222--.-220 202-020-0222 - eee 1. 8S. stellata.

154 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Leaves opposite, never whorled.
Stems glabrous, or rarely with a few hairs near the inflorescence.
Plants glaucous; flowers numerous, in loose terminal panicles...... 2. S. latifolia.
Plants green; flowers few, axillary or terminal, usually solitary........- 8.8. alba.
Stems hairy, at least near the base.
Plants perennial; inflorescence dense, the petals large, pink, showy.
4... caroliniana.
Plants annual; inflorescence loose and open, the petals white, or pinkish and
very small.
Plants stout, viscid-hairy throughout; petals white; calyx 20-30 mm. long.
5. S. noctiflora.
Plants slender, finely hairy below, the upper internodes glabrous except for
glutinous rings; petals pink, inconspicuous; calyx 4-6 mm. long.
6. S. antirrhina.

1. Silene stellata (L.) Ait. . STARRY CAMPION.
Woods, especially along the upper Potomac; common. June-Aug. Eastern U. 5.
Silene armeria L., sweet william catchfly, was collected by Ward, June 2, 1878,

in the Insane Asylum woods. Native of Eur.; a glabrous annual, the pink flowers

in dense cymes.

2. Silene latifolia (Mill.) Britten & Rendle. BLADDER CAMPION.
Woodside and Ammendale. Native of Eur. and Asia; adventive in many part
of the U. S.

8. Silene alba Muhl. SNOWY CAMPION,

Islands of the Potomac and on the flats below High Island; also near Glen Echo
and in Rock Creek Park; abundant along the Patuxent at Laurel. June-July.
Northern states, south to Md. (S. nivea Otth.)

4, Silene caroliniana Walt. WILD PINK.

Sandy soil; rather common, especially along the upper Potomac. Apr.—June.
Eastern U.S. (8. pennsylvanica Michx.)

5. Silene noctiflora L. NIGHT-FLOWERING CATCHFLY,

Well established about Beltsville; occasional elsewhere. Native of Eur.; adven-
tive in many parts of the U. 8.

6. Silene antirrhina L. SLEEPY CATCHFLY.

Common in dry or sterile soil. May-June. Widely distributed in N. Amer.

S. antirrhina divaricata Robinson, with more slender spreading pedice!s and apeta-
lous flowers, has been collected on High Island and Plummers Island, and at Chain
Bridge.

3. LYCHNIS L. .
1. Lychnis alba Mill. WHITE CAMPION.

Bunker Hill and Chevy Chase Lake. Native of Eur.; sparingly adventive in the
northeastern U. 8. (2. vespertina Sibth.)

The flowers in this species are pistillate and staminite, the two kinds borne on the
same or separate plants.

A single specimen of Lychnis flos-curui L. was eollected at “Washington. Intro-
duced,” in 1869 by H. Brumme!. Native of Eur.; cultivated and rarely adventive
in the northeastern U. 8.

4, DIANTHUS L.

1. Dianthus arms 1a L. DEPTFORD PINK.
Usually in dry soi!; common. May-July. Native of Eur.; naturalized in eastern
N. Amer. :

A close relative of the common cultivated sweet william (Dianthus barbatus L.).
The carnation, also, belongs to this genus.

FLORA OF THE DISTRICT OF COLUMBIA. 155

5. VACCARIA Medic.
1. Vaccaria vulgaris Host. COWHERB.
Occasional about Washington and Rosslyn. Adventive from Eur. in many parts
of the U.S. (Saponaria vaccaria L.; V. vacearia Britton.)

6. SAPONARIA L.
1. Saponaria officinalis L. BouNCING BET.
Common in waste ground and along roadsides. June—Oct. Native of Eur.; widely
naturalized in the U. 8.
The flowers are often double; they vary in color from almost white to deep pink.

55. NYMPHAEACEAE. Waterlily Family.

Petals very small and thick, green; sepals much larger than the petals, green, tinged
with yellow; fruit naked; leaves usually longer than broad, green.

1. NYMPHAEA.

Petals large and showy, white or pinkish; sepals equaling or shorter than the petals,

green; fruit covered with the bases of the petals; leaves as broad as long, purple

beneath 2.2... eee cece ee ee eee ee ee erence ncneee 2. CASTALIA.,

1. NYMPHAEA L.

1. Nymphaea advena Soland. YELLOW PONDLILY.
Shallow water or marshes; common. May-Sept. Northern states, south to N. C.
(Nuphar advena Ait.)

A colony of plants is shown in plate 24.
2, CASTALIA Salisb.

1. Castalia odorata (Dryand.) Woxlv. & Wood. WHITE WATERLILY.

Floating in water, Fourmile Ron, Laurel, near Alexandria, and probably elsewhere;
formerly found in pools at Great Falls. June-July. Eastern N. Amer. (Nymphaea
odorata Ait.)

56. CABOMBACEAE. Water-shield Family.

Leaves mostly dissected into numerous capillary lobes; stamens 3-6..1. CABOMBA.
Leaves oval, the peliole attached to the middle of the blade; stamens 12~18.
2. BRASENIA.
1. CABOMBA Aubl.
1, Cabomba caroliniana A. Gray.

Well established formerly in the fishponds in Potomac Park, but these have been
filled and the plants destroyed; reported by Steele from the Eastern Branch.
Southeastern U.S.

Sometimes known as Washington plant.

2. BRASENIA Schreb.
1. Brasenia schreberi Gmel. WATER-SHIELD.

Edges of pools along the Potomac near Little Falls; Laurel; rare. June—July.
Eastern N. Amer. and on the Pacific coast; also Cuba and Mex. (B. peltata Pursh.)

57. CERATOPHYLLACEAE, MHornwort Family.
1. CERATOPHYLLUM L. Hornwort.

1. Ceratophyllum demersum L.

Ponds and sluggish streams near the Potomac from Plummers Island southward;
frequent. Throughout the U.S.

Readily propagating by buds; rarely fruiting.

156 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

58. RANUNCULACEAE. Crowfoot Family.

Stem leaves all opposite or whorled (or only part of them opposite in Ficaria, with
very short stems, the flowers often appearing to be on naked scapes).

Leaves of the stem whorled, usually only a single whorl (sometimes 2 whorls in

Anemone), sometimes reduced to sepal-like bracts borne at the base of the

flower.
Plants wholly glabrous; roots tuberous; flowers in a terminal umbel. Sepals
white; leaves compound ......-.--. cece cece ce cece ee eeeee 7. SYNDESMON.

Plants more or less hairy; roots fibrous; flowers solitary.
Basal leaves 3-lobed, the lobes rounded at the apex; stem leaves reduced to 3
entire bracts borne at the base of the flower...........---- 6. HEPATICA.
Basal leaves compound or with numerous lobes, the divisions acute; stem
leaves well developed, deeply lobed or compound, the flowers on long
naked stalks......-.-...-2------ 20022 e ee eee eee eee eee ...56. ANEMONE.
Leaves of the stem opposite, usually of numerous pairs, never whorled.
Plants wholly glabrous; leaves heart-shaped, the blades much shorter than the
petioles; roots fleshy; fruits not tailed............-...--.---- 10. FICARIA.
Plants more or less hairy; leaves never heart-shaped, sessile or the petioles much
shorter than the blades; roots not fleshy; fruits with long hairy tails.
Flowers panicled, the sepals 1 cm. long or shorter, spreading, thin.
12, CLEMATIS.
Flowers solitary on long stalks, the sepals 1.5-3 cm. long, erect, the tips recurved,
thick and leathery............-..-- cece eee e cece ec eeeeeee 13. VIORNA.
Stem leaves all alternate, sometimes only one.
Flowers in racemes. Leaves compound or deeply lobed.
Flowers irregular, one of the sepals produced into a long spur; leaves not over
10 em. wide ............0.2 0022-2 38. DELPHINIUM.
Flowers regular, none of the sepals spurred; leaves often 30 em. wide or larger.
1, CIMICIFUGA.
Flowers variously arranged, but never in racemes.
Flowers all or mostly on recurved stalks, blue or red and yellow; fruit a many-
seeded pod.
Leaves simple, deeply lobed; flowers blue, very irregular, one of the sepals
large and hooded.......-........2-2-++--22-2-2----------- 4, ACONITUM.
Leaves compound (except the uppermost), composed of slender-stalked leaf-
lets; flowers red and yellow, the sepals produced into long slender spurs.
2. AQUILEGIA.
Flowers on straight, erect or ascending stalks, yellow or white; fruit of achenes.
Petals present, yellow; basal leaves comparatively small, rarely 10 cm. wide.
Leaves simple or compound...........-..----------- 9. RANUNCULUS.
Petals none, the sepals often petal-like, green or white; basal leaves large,
usually 20 cm. wide or larger,
Leaves simple, deeply lobed; flower stalks finely hairy.
8. TRAUTVETTERIA.

Leaves compound, composed of numerous leaflets; flower stalks glabrous.
11. THALICTRUM.

1, CIMICIFUGA lL.

1. Cimicifuga racemosa (1..) Nutt. BLACK SNAKEROOT,

Rich woods; common. June-July. Eastern U.S.

FLORA OF THE DISTRICT OF COLUMBIA. 157

2. AQUILEGIA L.
1, Aquilegia canadensis L. CoLUMBINE.
Cliffs and rocky woods, chiefly along the upper Potomac; common. Apr.—May.
Eastern N. Amer.
The columbine most commonly cultivated in gardens is an Old World species,
Aquilegia vulgaris L.
8. DELPHINIUM I... Larkspur.

Plants annual; stem leaves mostly sessile or nearly so, the lobes 1 mm. wide or nar-

rower; fruit a single pod..............22.2-----0--- +--+ -- ee eee 1. D. ajacis.
Plants perennial, with tuberous roots; stem leaves long-petioled, the lobes broad,
2 mm. wide or often much wider; fruit of 8 pods ..........---- ..2. D, tricorne,
1. Delphinium ajacis L. RockET LARKSPUR.

Fields and waste ground; occasional. June-Aug. Native of Eur.; widely
adventive in N. Amer. (D. consolida of Ward’s Flora.)

Flowers blue, pink, or white.
2. Delphinium tricorne Michx. DWARF LARKSPUR.

Islands of the Potomac and at a few other places along the river; rare and now
almost extinct. Apr.-May. Pa. to Ga. and westward.

4. ACONITUM L.

1, Aconitum uncinatum L. MonksHoop,
Low woods and thickets; infrequent. Sept. Pa. to Ga. and westward.
A form with nearly white flowers has been found by Titus Ulke.

5. ANEMONE LL. ANEMONE.

Stem leaves not stalked; basal leaves simple, deeply lobed. Fruit pubescent with

straight hairs... 2... eee eee eee eee eee 1, A. canadensis.
Stem leaves stalked; basal leaves ‘compound.

Plants 30-60 cm. high or larger, very hairy, with thick erect rootstocks; sepals

(petal-like) silky-hairy outside...........-.....---+-+---++-- 2. A. virginiana.
Plants 10-20 cm. high, nearly glabrous, with very slender creeping rootstocks; sepals
glabrous.....-.-- 2-2-2 cece ee ee eee eee ee eee ee eee e teens 3. A, quinquefolia.

1. Anemone canadensis L.

Woods below Congress Heights, M: ay, 1898 (Steele). Widely distributed in N. Amer.
2, Anemone virginiana L.

Woods and meadows, chiefly along the upper Potomac; frequent. June—Aug.
Eastern N. Amer.

8. Anemone quinquefolia L. Woop ANEMONE.
Woods; occasional. Apr.-May. Eastern N. Amer. (A. nemorosa of Ward’s Flora.)

6. HEPATICA Mill.
1. Hepatica americana Ker. HEPATICA.
Woods; common. Feb.-Apr. Eastern N. Amer. (Anemone hepatica of Ward’s
Flora; i. hepatica and H. triloba of American authors.)
One of the very earliest of spring flowers. Flowers bluish, pinkish, or nearly white.
The flowers are shown in plate 25A.

7. SYNDESMON Hoffmannsegg.

1. Syndesmon thalictroides (L.) Hoffmannsegg. RUE ANEMONE.
Woods; common. March-Apr. Eastern U. 8. (Thalictrum anemonoides Michx.;
Anemonella thalictroides Spach.)
Double-flowered plants occur occasionally.

158 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

8. TRAUTVETTERIA Fisch. & Mey.

1, Trautvetteria carolinensis (Walt.) Vail. FALSE BUGBANE.
Low wet ground; Mount Vernon; Difficult Run. June-July. Southern states,

north to Pa.
9, RANUNCULUS L. Burrercupr.

Basal leaves, at least most of them, entire or shallowly toothed.
Upper stem leaves entire or very shallowly toothed. Plants glabrous.

Plants annual; flowers 4-6 mm. broad; fruits not beaked......... 1. BR. pusillus.
Plants perennial, the stems rooting at the joints; flowers 12-15 mm. broad; fruits
beaked .... 2.2.2... 2. eee 2. R. obtusiusculus.

Upper stem leaves compound or deeply lobed.
Siems glabrous; basal leaves cordate at the base; receptacle hairy,
3. R. abortivus:
Stems loosely hairy, at least below; leaves not cordate at the base; receptacle
glabrous. .........22-----.2.222---0-0-2 222222222 e eee eee 4. R. micranthus.
Basal leaves compound or deeply lobed.
Leaves glabrous; fruits noi margined, Petals about as long as the sepals.
5. R. sceleratus.
Leaves hairy, at least along the veins beneath; fruiis with an evident margin.
Beak of the fruit long, slender, and recurved; basal leaves lobed, not divided.
Petals shorter than the sepals............- Leese .6. BR. recurvatus.
Beak of the fruit long and straight, or very “short and recurved: basal leaves
usually divided to the base or composed of distinct leaflets.
Beak of the fruit long and straight. Petals much longer than the sepals.
Roots slender; plants, at least in age, producing long runners; petals broadly

obovate...... 0.2 eee eee eee ee eee 7. R. septentrionalis-
Roots fleshy-thickened; plants erect or nearly so, without runners; petals
oblong......--.-.--- 2222-2 eee eee eee eee eee ees 8. R. hispidus.

Beak of the fruit short and recurved.
Plants wi h long runners. Petals much longer than the sepals. .9. R. repens.
Plants erect or ascending, wi'hout runners.
Petals about 3 mm. long; head of fruits cylindric, much longer than thick.
10. R. pennsylvanicus.
Petals 7-12 mm. long; head of fruits globose, about as thick as long.
Stem bulblike at the base; middle division of the basal leaves stalked;

sepals reflexed, almost as long as the petals......-.. 11. R. bulbosus.
Stem not bulblike at the base; divisions of the basal leaves all sessile ;
sepals not reflexed, much shorter than the petals....... 12. R. acris.

1. Ranunculus pusillus Poir.

Marshes along the Potomac and Eastern Branch. Apr.-May. Eastern U.S.
2. Ranunculus obtusiusculus Raf.

Marshes along the Eastern Branch and Hunting Creek. June-July. Eastern U.S.
(R. ambigens S. Wats.)
8. Ranunculus abortivus L.

Woods or moist soil; common. Apr.-May. Eastern N. Amer. (R. ruderalis
Greene. )

R. ruderalis was based upon specimens from Linden and Takoma Park. It is a form
with dull green leaves, those of the more common form being lustrous.
4. Ranunculus micranthus Nutt.

Rich woods along the upper Potomac; frequent. Apr-May. Eastern N. Amer.,
west to Colo. (R. abortivus micranthus A. Gray; R. holmit Greene.)

R. holmii was based upon material from our region.

FLORA OF THE DISTRICT OF COLUMBIA. 159

5. Ranunculus sceleratus L.
Marshes along the Potomac and Eastern Branch; frequent. May-July. Widely
distributed in temperate N. Amer.; also Eur. and Asia.

6, Ranunculus recurvatus Poir.
Damp woods and thickets; common. Apr._May. Eastern N. Amer.

7. Ranunculus septentrionalis Poir.

Low ground along the Potomac; common. Apr.-May. Eastern N. Amer. (R.
repens nitidus and R. repens, in part, of Ward’s Vlora.)
8. Ranunculus hispidus Michx.

Usually in dry woods and thickets; common. Apr.-May. Eastern U. 8S. (R.
repens hispidus and FR. repens, in part, of Ward’s Flora.)
9. Ranunculus repens L.

Marshes or waste ground; occasional. Apr.Sune. Widely distributed in N.
Amer., largely naturalized from Eur.

10. Ranunculus pennsylvanicus L. f.

Swamp near Aqueduct Bridge, August, 1888 (Holm). Widely distributed in tem-
perate N, Amer.
11. Ranunculus bulbosus L.

Fields and waste ground; abundant. Apr.June. Native of Eur.; widely natural-
ized in eastern N. Amer.

12. Ranunculus acris L.
Fields and waste ground; common. May-July. Native of Eur.; widely natural-
ized in N. Amer.
10. FICARIA Huds.
1. Ficaria verna Huds. LESSER CELANDINE.
Shaded banks, Rock Creek Park. Apr. Native of Eur. and Asia; occasionally
adventive in the northeastern U.S. (Ranunculus ficeria L.; #. ficaria Karst.)

11. THALICTRUM. Merapow-RuvueE.

Leaflets waxy-glandular beneath. Fruits not stalked; filaments slender, drooping.

1. T. revolutum.
Leaflets glabrous beneath or very finely hairy, never glandular.

Filaments club-shaped, not drooping, the apex nearly as wide as the anthers.
Fruits not stalked; leaflets mostly longer than broad, usually finely hairy
beneath ... 2.2... eee cee cee cee ec eee eee eeeeeeee 2. T. polygamum.

Filaments threadlike, soon drooping.

Stem leaves on long slender stalks; plants flowering in April or early May. Leaflets
glabrous, mostly as broad as long; fruits not stalked, not glaucous.
3. T. dioicum.

Stem leaves mostly sessile, sometimes on short stout stalks; plants flowering
mostly from late May to July.
Fruits sessile; leaflets mostly longer than broad.............. 4, T. dasycarpum.

Fruits short-stalked; leaflets mostly as broad as long or broader.

5. T. caulophylioides.
1. Thalictrum revolutum DC.

Woods and low ground; common, June. [astern U.S. (7. purpurascens ceriferum
Avstin.)
2. Thalictrum polygamum Muhl.

Swamps or low woods; frequent. May—July. Eastern N. Amer. (7. cornuti of
Werd’s Flora.)
3. Thalictrum dioicum L.

Moist woods or thickets along Rock Creek and the upper Potomac. Apr.—May.
Kastern U. 5.

160 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

4. Thalictrum dasycarpum Fisch. & Lall.

Woods and thickets; frequent. May-July. Eastern U. 8S. (7. purpurascens of
Ward’s Flora, in part.)
5. Thalictrum caulophylloides Small.

Low ground along the upper Potomac; common. May-June. Md. to Tenn. (7.
purpurascens of Ward’s Flora.)

12. CLEMATIS L.

1. Clematis virginiana L. VIRGIN’S-BOWER.

Marshes or thickets along the Potomac and Hastern Branch; occasional. Aug.-
Sept. Eastern N. Amer.

Clematis paniculata Thunb. is reported to have escaped at several localities about
Chevy Chase (£. 7. Wherry). Native of Japan; widely cultivated. Distinguished
from (, virginiana by having more than 3, entire leaflets.

13. VIORNA Reichenb. LEATHER-FLOWER.

Plants erect; leaves sessile or nearly so, simple, entire............- 1. V. ochroleuca.
Plants climbing; leaves petioled, compound, composed of 3 or more leaflets, these
often lobed ..........-...0. eee eee ee eee ee teen et eee e eens 2, V. viorna.

1. Viorna ochroleuca (Ait.) Small.
Wooded hillsides along the Virginia side of the Potomac; occasional. Apr.-May.
Staten Isl., N. ¥., to Ga. (Clematis ochroleuca Ait.)

2. Viorna urnigera Spach.
Woods and thickets along the upper Potomac; frequent. June. Pa. to Ind, and
Ga. (Clematis viorna L.; V. viorna Small.)

59. BERBERIDACEAE. Barberry Family.

Veaves simple, deeply lobed, the blades peltate (the petiole not attached at the base

of the blade but above the base). Plants with 2 leaves at the top of a stout stem,

a single large white flower borne between the leaves; fruit yellowish green, about

5 em, long, pulpy.......---.-.----- 6.202 eee eee ee eee eee 1. PODOPHYLLUM.
Leaves compound, of 2 or more leaflets, never peltate. .

Leaflets 2, entire; leaves all basal; flowers solitary, on long scapes, white, showy,

fruit a capsule, opening by a lid.............-.+-------- 2. JEFFERSONIA.

Leaflets more than 2, coarsely lobed; leaves partly borne on the stems; flowers in

small panicles, small, purplish green; fruit fleshy, blue. .3. CAULOPHYLLUM.

Berberis vulgaris L., the barberry, has been collected as an escape at two or three
stations within our range. Native of Eur.; commonly cultivated and sometimes
escaping. Several other species of Berberis (with simple leaves) and of the closely
related genus Odostemon (with pinnate leaves) are frequent in cultivation.

1. PODOPHYLLUM L.
1. Podophyllum peltatum L. . MAY-APPLE.
Woods and thickets; common, Apr-May; fr. July. Eastern N. Amer,
Known also as mandrake, The large fruits are edible. The roots are used in
medicine. The flowers are shown in plate 26.

2. JEFFERSONITA Barton.
1. Jeffersonia diphylla (L.) Pers, TWIN-LEAF,

Islands of the Potomac; rare, but locally abundant. Apr. N. Y. to Towa and

Tenn.
The genus was named in honor of Thomas Jefferson. Plants in flower are shown in

plate 28B.

FLORA OF THE DISTRICT OF COLUMBIA. 161

3. CAULOPHYLLUM Michx.

1. Caulophyllum thalictroides (L.) Michx. BLUE COHOSH.
Rich woods on the islands and banks of the upper Potomac; rare. Apr. Eastern
N. Amer.

60. MENISPERMACEAE. Moonseed Family.
1. MENISPERMUM L.

1. Menispermum canadense L. MOONSEED.
Low thickets, climbing over shrubs; along Rotk Creek and the upper Potomac.
May-June; fr. autumn. Eastern N. Amer.

61, MAGNOLIACEAE. Magnolia Family.

Leaves oval or oblong, entire; flowers white, very fragrant; anthers facing in; fruit
an ovoid cone of rose-colored fleshy carpels, at length turning dark brown.
1. MAGNOLIA.
Leaves lobed, truncate or broadly notched at the apex; flowers greenish yellow,
orange inside, slightly fragrant; anthers facing out; fruit a dry oblong cone.
2, LIRIODENDRON.
1, MAGNOLIA L.
1. Magnolia virginiana L. SWAMP MAGNOLIA.
Swamps and marshy places bordering streams, especially along Indian Creek, from
Beltsville to Kenilworth and southeastward. May-June. Mass. to Fla. (IM. glauca L.)
The bark, rich in tannin, was used as a tonic and febrifuge, and its pleasant aromatic
taste gave to the tree the name swamp sassafras, The fresh leaves and bark were
used for dyeing. Also known as sweet bay.

2, LIRIODENDRON L.

1. Liriodendron tulipifera L. TULIP TREE,
Rich soil throughout the region. May-June. Eastern N. Amer.
A magnificent tree, sometimes 40 meters high, valued for its timber, which is com-
monly called poplar or white wood.

62. ANNONACEAE. Custard apple Family.

1, ASIMINA Adans.
1. Asimina triloba Dunal. Pawpaw.

Moist woods; comnion, especially along the banks of streams. Apr.—May. Southern
states, north to Lake Erie.

Flowers appearing with the leaves, sometimes abnormal, with 9 instead of 6 petals,
these pale yellowish green at first, turning dark purple or maroon and increasing in
size. Fruit usually solitary, but sometimes in clusters of 2 to 5 from the same flower,
edible, turning brown or black after the first frost. A food-staple of the aborigines.
The generic name is derived from the Indian Assimin, whence the common name
Assiminier applied to the tree by the early French colonists. The English common
name is misleading, since the species is not even remotely related to the true pawpaw,
or papaya, of the tropics (Carica papaya).

63. LAURACEAE. Laurel Family.

Plants trees or shrubs, with rough bark; leaves normally 3-lobed; staminate flowers
with 4-celled anthers; pistillate flowers with 6 imperfect stamens and an ovoid
ovary; fruit blue............----- 2-2 eee eee eee eee eee teen 1, SASSAFRAS.

69289—19——11

162 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Plants shrubs, with smooth bark; leaves entire; staminate flowers with 2-celled
anthers; pistillate flowers with 12-15 imperfect stamens and a globose ovary; fruit
bright red..... 22220000020 eee eee eee bec e cece cece eee 2, BENZOIN.

1, SASSAFRAS Nees.

1, Sassafras variifolium (Salisb.) Kuntze. SASSAFRAS,

Very common in woods and along roadsides, springing up in waste places like a
weed. Eastern N. Amer. (8. officinale Nees & Ebetm.; S. sassafras Karst.)

A tree, usually of moderate size, with us rarely exceeding 10 meters; aromatic;
flowers appearing about the middle of April, before the leaves; leaves variable on the
same branch, sometimes entire or mitten-shaped instead of 3-lobed, used like bay
leaves for flavoring food; bark of root used for making tea and for dyeing, the source
of an aromatic oil used in perfumery, Snd for flavoring sweetmeats and medicines.
A few trees are shown in plate 27.

2. BENZOIN Fabr.

1. Benzoin aestivale (L.) Nees. SPICE BUSH.

Common in moist woods and swamps and along streams. Hastern N. Amer. (Lin.
dera benzoin Blume; B. benzoin Coulter.)

A spicy, fragrant bush, 1-4 meters high; flowers appearing in April, before the leaves;
fruit ripe in August. Used by the Indians and early settlers as a remedy for fevers
and therefore sometimes called fever bush; also wild allspice, from the use of the
berries to take the place of the true allspice of the West Indies.

64. PAPAVERACEAE. Poppy Family.

Leaves all basal, glabrous; plants perennial, with thick creeping rootstocks; flowers
White... 0... cece ce eee cece ccc cececceeeeee 1. SANGUINARIA.
Leaves, at least part of them, scattered along the stems, hairy; plants never with
creeping rootstocks; flowers yellow or red.
Flowers solitary, on very long stalks, red; fruit opening only at the top, less than

twice as long as thick. ..........2.0000000 0000 e eee eee 2, PAPAVER.
Flowers in umbels, on short stalks, yellow; fruit opening for its whole length, several
times as long as thick. ........220.2000000..00.0020-- 0. 3. CHELIDONIUM.

1. SANGUINARIA L. |
1. Sanguinaria canadensis L. BLoopRooT.

Woods; common. March-Apr. Eastern N. Amer. (S. dilleniana Greene.)

Juice orange-red. The flowers are shown in plate 28A.

Argemone mexicana L., prickly poppy, has been collected a few times in waste
ground about Washington. Native of the American tropics; occasionally adventive
in the eastern U.S. Leaves spiny, blotched with white.

2. PAPAVER L. Poppy.

1. Papaver dubium L.

Fields and waste ground; infrequent. May-June. Native of Eur.; adventive in
the eastern U. S.

3. CHELIDONIUM L.

1, Chelidonium majus L. CELANDINE.

Low woods and waste ground along the Potomac; occasional. Apr.~May. Native
of Eur.; naturalized in the eastern U.S.

FLORA OF THE LISTRICT OF COLUMBIA. 163
65. FUMARIACEAE, Fumitory Family.

Plants perennial, with tuberous or bulblike roots; leaves all basal; flowers with
2 spurs at the base......-.-.- 2-22 eee eee eee eee eee eee 1, BIKUKULLA.
Plants annual or perennial, with fibrous roots; leaves mostly scattered along the
branched stems; flowers with only one spur at the base.
Flowers yellow; fruit several times as long as broad, several-seeded.,
2, CAPNOIDES.
Flowers purplish; fruit globose, l-seeded.........-.------.---. ..8, FUMARIA.

1. BIKUKULLA Adans.

Roots with tubers; spurs much shorter than the upper part of the flower.
1. B. canadensis. .
Roots bulblike; spurs almost or quite as long as the upper part of the flower.
2. B, cucullaria.
1. Bikukulla canadensis (Goldie) Millsp. SQUIRREL CORN.
Rich woods on the islands and banks of the upper Potomac; rare. Apr. Eastern
N. Amer. (Dicentra canadensis Walp.)
Flowers white tinged with pink. The flowers are shown in plate 29B.
2, Bikukulia cucullaria (L.) Millsp. DuTCHMAN’S BREECHES.
Rich woods along the upper Potomac; occasional. Apr. Eastern N, Amer.
(Dicentra cucullaria Bernh.)
Flowers white tinged with pale yellow. The flowers are shown in plate 29A.

2, CAPNOIDES Adaas.

1, Capnoides flavulum (Raf.) Kuntze. CORYDALIS.
Woods; common along the Potomac, occasional elsewhere, March-May. Northern
states, south to Va. (Corydalis flavula DC.)

3. FUMARIA L.
1, Fumaria officinalis L. Fumirory.
Occasional in waste ground about Washington. May-June. Native of Eur.;
adventive in eastern N, Amer.

66. BRASSICACEAE. Mustard Family.

Leaves palmately divided, the root leaves with 3 leaflets; plants with fleshy tuber-
like rootstocks. Flowers white or purple; pods long and narrow. .20. DENTARIA.
Leaves simple or pinnately divided, when pinnate the leaflets usually more than 3;
plants never with fleshy rootstocks.
Upper stem leaves sessile and clasping at the base, with conspicuous auricles,
entire or toothed, the lower leaves various.
Petals yellow. Pods long and slender; lower leaves toothed or lobed.

22. BRASSICA.
Petals white.

Lower leaves pinnately lobed; pods triangular............-------- 4, BURSA.
Lower leaves merely toothed; pods not triangular.
Pods several times longer than broad, flat.......-------.------ 18. ARABIS.

Pods less than twice as long as broad, often as broad as long.
Upper leaves entire; stems long-hairy below; pods obovoid, turgid, rounded
at the apex..........-- 2202-0 - ee ee ee eee eee weeeeeee 3, CAMELINA.
Upper leaves finely or coarsely toothed; stems glabrous below or with
very short minute hairs; pods flattened, notched or pointed at the apex.
Pods winged, deeply notched at the apex, with 2 or more seeds in each
cell; stems glabrous.....-.....-.-.-----+--- e+ 2eee 10. THLASPI.
Pods not winged, pointed or shallowly notched, with one seed in each
cell; stems finely hairy, at least below............ 9, LEPIDIUM.

164 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Upper stem leaves petioled or sessile, never clasping.
Leaves entire or toothed, never pinnately lobed or divided.
Plants with naked stems, the leaves in a basal rosette. Petals white; pods
oval or oblong, about twice as long as wide, flat............... 1, DRABA.
Plants with leafy stems.
Leaves glabrous. Plants perennial; petals white.
Upper leaves petioled; plants with the odor of garlic. Pods long and
Blender...... 2... eee eee cece eee e nent tenet enees 11, ALLIARIA.
Upper leaves sessile; plants not with the odor of garlic.
Basal leaves much longer than broad, mostly 20-30 cm. long or larger,
conspicuously toothed; pods less than twice as long as thick.
7. ARMORACIA.
Basal leaves mostly as broad as long, rarely over 5 cm, long, usually
entire; pods much more than twice as long as thick.
19, CARDAMINE,
Leaves, at least the luwer ones, conspicuously hairy.
Petals pink or purple, about 2 cm. long; pods long and slender, swollen
over the seeds. Leaves conspicuously toothed....... 15. HESPERIS,
Petals white or yellow, not more than 0.5 cm, long; pods not swollen over
the seeds.
Petals yellow; pods long and slender, not flattened; leaves entire or
NEATLY SO... eee eee eee eee eee .....12. CHEIRINIA.
Petals white; pods about as broad ag long, or long, slender, and flat.
Pods obovoid, nearly as broad as long; leaves all linear or nearly so,
entire............- Jee e ee cece eee eee eee e eee 2, KONIGA.
Pods long and slender, flat; leaves, at least. most of them, broader than
linear, often toothed,
Plants annual, with a conspicuous basal rosette of leaves; leaves
mostly entire; pods less than 2 cm. long...16. ARABIDOPSIS.
Plants perennial or annual, usually without basal rosettes of leaves;
leaves all or nearly all toothed; pods over 3 cm. long.

18, ARABIS.
Leaves, at least some of them, pinnately lobed or divided.

Plants with conspicuously dimorphous leaves, growing in water, the submerged
leaves dissected into threadlike segments. Petals white; pods short and

thick, less than twice as long as thick.................-.- 8. NEOBECKIA,
Plants not with dimorphous leaves, none of the leaves dissected into threadlike
segments.

Upper stem leaves linear or nearly so, most of them entire. Petals white.
Pods as broad as long, shorter than the pedicels; plants annual; petals less

than 2 mm. long, sometimes wanting..............-.- 9. LEPIDIUM.
Pods several times longer than broad, much longer than the pedicels; petals
5-7 mm, long............. 22.0222. eee eee eee eee ee eee 18, ARABIS.

Upper stem leaves broader than linear, toothed or pinnately lobed or divided.
Petals white or purple.
Pods less than twice as long as thick; basal leaves simple. Plants with

thick fleshy roots; petals white........ cence eens 7, ARMORACIA.
Pods several times as long as thick; basal or lower leaves pinnately
divided.
Upper leaves simple; pods not splitting when ripe; petals mostly
purple... 22.2.2. eee cece cece eee c cece eens eens 23. RAPHANUS.
Upper leaves pinnately divided; pods splitting when ripe; petals
white.

Pods flat, straight; leaflets of the upper leaves more than twice as
long as broad; plants not floating in water...19. CARDAMINE.

FLORA OF THE DISTRICT OF COLUMBIA. 165

Pods not flattened, curved; leaflets less than twice as long as
broad, often as broad as long; plants usually floating in water.
6. SISYMBRIUM.
Petals yellow.
Petals 8-15 mm. long,
Pods slender, not over 1 mm, thick; upper leaves pinnately divided
into linear lobes.........-.-----0-+- ee ee eee eens -.-.14, NORTA.
Pods stout, 2-6 mm, thick; upper leaves with very broad lobes, or
sometimes merely toothed.
Beak of the pod flattened or angled; pods often hairy.
21. SINAPIS.
Beak of the pod not flattened or angled; pods glabrous.
22. BRASSICA.
Petals 5 mm, long or shorter.
Plants very hairy; pedicels in fruit closely appressed to the stem.
13, ERYSIMUM.
Plants glabrous or nearly so; pedicels spreading or ascending, never
closely appressed,
Pods less than 1.5 cm, long, on slender pedicels; terminal lobe of the

leaf much longer than broad............-----++ 5. RADICULA.
Pods mostly over 3 cm, long, on very stout pedicels; terminal: lobe
of the leaf often as broad as long...........-+--.-- 17. CAMPE.
1. DRABA L.
1. Draba verna L. WHITLOW GRASS.

Dry or moist soil; common. March-Apr. Native of Eur, and Asia; widely natu-
ralized in N. Amer.
The plants are very variable, especially in the form of the pods.

2, KONIGA Adans.

1, Koniga maritima (L.) R. Br. SWEET ALYSSUM.
Waste ground about Washington and Alexandria; obtained at three stations in
1915. Native of Eur.; commonly cultivated and sometimes escaping. (Lobularia
maritima Desv.)
3. CAMELINA Crantz.

1, Camelina microcarpa Andrzej. FALse FLAX.
Roadsides, grain fields, and waste ground; frequent. May-June. Native of Eur.;
widely naturalized in N. Amer. (C. sativa of Ward’s Flora.)

4, BURSA Weber.

1. Bursa bursa-pastoris (L.) Weber. SHEPHERD’S-PURSE.
Fields and waste ground; common. March-June. Native of Eur.; widely natu-
ralized in N. Amer. (Capsella bursa-pastoris Medic.)
The leaves are often used as ‘‘greens.’? The common form of this plant has a tri-
angular pod, acute at the upper corners, Another form of occasional occurrence
has an obcordate pod; the stems are usually lower and tinged with red.

5. RADICULA Hill. YELLOW cress.

Flowers nearly sessile. Plants annual or biennial, glabrous...... 1. R. sessiliflora.
Flowers long-pediceled.

Plants perennial, with slender creeping rootstocks; petals about 4 mm. long, bright

yellow; leaves mostly pinnate-parted, with narrow segments; pods slender,

8-12 mm. long.........-...-.-.--- cece eeeeeeee beeen eens 2. B. sylvestris.

166 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Plants annual or perennial, with fibrous roots; petals not over 2 mm. long, dull
yellow or greenish; leaves mostly pinnate-lobed, with broad segments; pode
thick, 7 mm. long or mostly shorter.

Plants very hairy, erect; pods almost as broad as long..........-. 3. R. hispida,
Plants glabrous or nearly so; pods twice as long as broad or longer.
Stems erect; pedicels usually longer than the pods.....--.... 4. R. palustris.
Stems spreading; pedicels shorter than the pods............--. 5. R. obtusa.

1. Radicula sessiliflora (Nutt.) Greene.

Reported by Holm from flats befow Chain Bridge. Southern states, north to Va.
(Nasturtium sessiliflorum Nutt.; Roripa sessiliflora Hitche.)

2. Radicula sylvestris (I.) Druce.

Open fields and low ground; frequent. May-July. Native of Eur. and Asia;
widely naturalized in eastern N. Amer. (Nasturtium sylvestre R. Br.; Roripa
sylvestris Besser.)

3. Radicula hispida (Desv.) Britton.

Wet ground along the Eastern Branch. June-Aug. Widely distributed in N.-
Amer.; also in Eur. (Nasturtium hispidum DC.: Roripa hispida Britton; Radicula
palustris hispida Robinson.)

4. Radicula palustris (L.) Moench.

Low ground along the Potomac. June-Sept. Widely distributed in N. Amer.
in part naturalized from Eur. (Nasturtium palustre DC.; Roripa palustris Besser.)
5. Radicula obtusa (Nutt.) Greene.

Jollected several times about Washington, the localities not indicated; doubtless
adventive. Native farther west. (Nasturtium oblusum Nutt.; Roripa obtusa Britton.)

6. SISYMBRIUM L.

1. Sisymbrium nasturtium-aquaticum L. WATERCRESS.

In streams; occasional. May-autumn. Native of Eur. and Asia; widely natu-
ralized in N. Amer. (Nasturtium oflicinale R. Br.; Radicula nasturtium-aquaticum
Britten & Rendle. }

7. ARMORACIA Gaertn., Mey. & Schreb.

1. Armoracia rusticana Gaertn., Mey. & Schreb. HorSERADISH,
Occasional by roadsides and in waste ground. Native of Eur.; common in cultiva-
tion and sometimes escaping. (Nasturtium armoracia Fries; Roripa armoracia Hitche. ;
Radicula armoracia Robinson; A. armoracia Britton.)
The grated roots furnish the well-known condiment.

8. NEOBECKIA Greene.

1. Neobeckia aquatica (Eaton) Britton. LAKE CRESS

In a pool among the rocks below Great Falls; collected only by Ward, in 1879 and
1882. June—July. Eastern N. Amer. ( Nasfurtiwm lacustre A. Gray; Roripa amer-
cana Britton: Radicula aquatica Robinson.)

9. LEPIDIUM L.,

Stem leaves with tapering bases. Plants glabrous or nearly so; pods shallowly
notched at the top.........-.....---.02---22---02-2 ee eee 1. L. virginicum.
Stem leaves with auricled clasping bases.
Pods deeply notched, winged; branches ot the inflorescence densely and finely
Hairy... 2. ee nee eee neta eee eeeee 2. L. campestre.
Pods pointed, not winged; branches of the inflorescence glabrous or nearly so.
3. L. draba.

FLORA OF THE DISTRICT OF COLUMBIA. 167

1. Lepidium virginicum L. PEPPERGRASS.

Fields and waste ground; abundant. May-July or later. Widely distributed in
N. Amer. and naturalized elsewhere.

The young plants are often used as ‘‘greens.’’

Lepidium densiflorum Schrad. (L. apetaluin of American authors) has been re-
ported from our region, but the specimens so determined are merely an apetalous
form of L. wirginicum.

2. Lepidium campestre L.

Fields and waste ground; common. May-June. Native of Eur.; widely natu-
ralized in N. Amer.
3. Lepidium draba L.

Collected a few times in waste ground about Washington. Apr.-May. Native of
Eur.; locally adventive in N. Amer.

10. THLASPI L. PENNY CRESS.

1. Thlaspi arvense L.

Found only a few times about Washington and Alexandria; not collected recently.
Native of Eur. and Asia; often adventive in N. Amer,

Thlaspi perfoliatum L., with clasping stem leaves, was collected in waste ground
near Virginia Avenue, Apr. 1899 (Steele), Native of Eur.; rarely adventive in N.
Amer,

11. ALLIARIA -Adans.
1. Alliaria officinalis Andrzej. GARLIC MUSTARD.

Waste ground or low woods along the Potomac; occasional. Apr.—May. (Sisym-
brium alliaria Scop.; Alliaria alliaria Britton.)

Readily distinguished from all our other members of the family by the garlic-like
odor of the plant.

12. CHEIRINIA Link.

1. Cheirinia cheiranthoides (L.) Link. WoRMSEED MUSTARD.
Low ground along the upper Potomac; rare. June-July. Widely distributed in
N. Amer.; alsoin Eur. (Hrysimum cheiranthoides L.)

13. ERYSIMUM L.

1. Erysimum officinale L. HEDGE MUSTARD.
Waste ground; common, May-June. Native of Eur.; widely naturalized in N.
Amer, (Sisymbrium officinale Scop.) .

The typical form with hairy pods is rare in North America, but it occurs in our
region. The common form in North America (Sisymbrium officinale leiocarpum DC.)
has glabrous pods.

14. NORTA Adans.
1. Norta altissima (L.) Britton. TUMBLE MUSTARD.

Occasional in old fields and waste ground. May-June. Native of Eur.; widely
adventive in N. Amer., and in the West often a troublesome weed. (Sisymbrium
altissimum L.)

Conringia orientalis (L.) Dum., hare’s-ear mustard, with clasping, entire, pale green
leaves, was collected in waste ground, Washington, May, 1899 (Steele). Native of Eur, ;
occasionally adventive in N. Amer.

15. HESPERIS L.

1. Hesperis matronalis L. DAME’S ROCKET.s
Occasional in woods and waste ground. May-June. Native of Eur.; sometime

eultivated and escaping.

168 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

16, ARABIDOPSIS (DC.) Schur.

1. Arabidopsis thaliana (L.) Britton. MOUSE-EAR CRESS.
Fields; common. March-May, Native of Eur. and Asia; widely naturalized in
N. Amer, (Sisymbrium thalianum Gay; Stenophragma thaliana Celak.)

17, CAMPE Dulac. WINTER cRESs.

Lobes of the leaves mostly 4-8 pairs; pods stout, sharply angled, on very stout short
pedicels....... wee cece eee eee e eee ence teen ee neeseeeeneneeees 1, C, verna.
Lobes of the leaves mostly 1-4 pairs; podsslender or stout, obtusely angled, on slender
pedicels.
Pods erect; petals pale yellow..................22+--- eee ceeeneeas 2. C. stricta.
Pods spreading or ascending; petals bright yellow.................- 8. C. barbarea.

1, Campe verna (Michx.) Heller.

Woods, fields, and waste ground; abundant. Native of Eur.; extensively natural-
ized in eastern N. Amer. (Barbarea praecox R. Br.; B. verna Aschers.)

This and the other species are much used as ‘“‘greens,’”’ and are commonly seen in
the markets in spring.
2. Campe stricta (Andrzej.) W. F. Wight.

Fields; abundant. Apr.-May. Native of Eur. Asia, and northern N. Amer.; with
us doubtless adventive. (Barbarea vulgaris of Ward’s Flora; B. stricta Andrzej.)

3. Campe barbarea (L.) W. F. Wight.
Fields; apparently not common. Apr.-May, Native of Eur. and northern N.
Amer.; naturalized in eastern N. Amer. (Barbarea vulgaris R. Br.; B. barbarea MacM.)

18. ARABIS L. Rock cress.

Lower leaves pinnately divided; stem leaves mostly linear and entire, tapering at the
base. Pods ascending.............- 202.2 cece cece cece eee ec eences 1. A. lyrata.
Lower leaves merely toothed; stem leaves all or mostly broader than linear, often
toothed.
Stem leaves, at least the upper ones, long-tapering at the base, not auricled, more
or less toothed; pods drooping. Plants hairy................- 2. A. canadensis.
Stem leaves never tapering at the base, more or less clasping and auricled; pods
ascending or spreading.
Plants glabrous throughout; upper leaves mostly entire, long-tapering at the
apex. Pods recurved-spreading..............0..20eeeeeeeee 3. A. laevigata.
* Plants hairy, at least below; upper leaves all or nearly all conspicuously toothed,
never long-tapering at the apex.
Petals more than twice as long as the calyx; pods strongly ascending; seeds

narrowly winged .......2... 26.2 cece cece ence cece ne eeeceeee 4, A. patens,
Petals equaling or very slightly exceeding the sepals; pods spreading; seeds
not winged......... ee cece ee eee eee eee eee eee 5. A. dentata.

Arabis hirsuta (1..) Scop. was reported from Sandy Landing by Ward, but the species
is not represented by specimens from our region.

1, Arabis lyrata L.

On rocks along the upper Potomac; frequent; also collected once along the Eastern
Branch, probably adventive there. March-June. Widely distributed in N. Amer ;
also in eastern Asia.

2. Arabis canadensis L. SICKLE-POD.

Woods along the Potomac and Rock Creek; frequent. May-June. Eastern U. 8.
3, Arabis laevigata (Muhl.) Poir.

Woods, often on rocks; frequent along the upper Potomac, occasional elsewhere.
Apr.-May. Eastern N. Amer.

FLORA OF THE DISTRICT OF COLUMBIA. 169

4, Arabis patens Sulliv.
Woods along the upper Potomac; occasional. Apr.-May. Minn. to Ala.
5. Arabis dentata Torr. & Gray.
Moist woods along the upper Potomac; occasional. Apr.-May. Northern states,
south to Va.
19. CARDAMINE L. Birrer CRESS.

Leaves simple, toothed or entire; stem bulblike at the base; petals about 10 mm.
long.

Sepals green; petals white; plants glabrous...........--+-+--+-++5+ 1. C. bulbosa.
Sepals purplish; petals usually purplish; plants more or less hairy, with very short
hairs... eee cece ee ee ee cece ee ee eee cece eee eee eeeeeseeeee 2. C. douglassii.

Leaves pinnately divided; stems not bulblike at the base; petals less than 4 mm.
long.
Leaflets hairy on the upper surface, those of the basal leaves rounded; stamens 4.
3, C. hirsuta.
Leaflets glabrous, comparatively narrow; stamens usually 6.
Leaflets of the stem leaves distinct, not running together along the rachis; plants

Of dry sil...... 2.2... eee eee eee eee eee eee ener er ceeenees 4, C. parviflora.
Leaflets of the stem leaves running together along the rachis, the rachis thus
winged; plants of wet soil.......-.-----+---+-+eeeeeeee 5. C. pennsylvanica.

1. Cardamine bulbosa (Schreb.) B.S.P.

Wet soil; frequent. Apr-May. Eastern U.8. (C. rhomboidea DC.)
2. Cardamine douglassii (Torr.) Britton.

Wet soil along the upper Potomac; infrequent. Apr.—May. Northern states, south
to Md.

Our specimens seem to be typical of the species except that the petals are mostly
white. The species is not very clearly distinct from C. bulbosa.
3. Cardamine hirsuta L.

Moist or wet soil in the region of Rock Creek Park and Chevy Chase; frequent.
Apr.-May. Pa. to Nebr. and N. C., probably adventive; Eur. and Asia.
4, Cardamine parviflora L.

Dry woods; occasional. Apr-May. Eastern N. Amer.; also in Eur.and Asia. (¢.
hirsuta sylvatica of Ward’s Flora.)
5. Cardamine pennsylvanica Muhl.

Wet soil, often along streams; common. Apr.-May. Eastern N. Amer. (C. hirsuta
of Ward’s Flora, chiefly.)

20. DENTARIA L. PeEppER-RooT.

Plants glabrous; leaflets of the basal leaves mostly ovate or rhombic-ovate, much
broader than those of the stem leaves; teeth of the leaflets short, usually rounded.
1. D. heterophylla.

Plants more or less hairy, at least above; leaflets of all the leaves similar, narrowly
oblong to linear, the teeth long and narrow, usually very acute...2. D. laciniata.

Dentaria diphylla L. has been reported from our region, but the species is not rep-
resented by specimens. It closely resembles D. heterophylla, but the rootstocks are
continuous, not jointed as in the latter species.

1. Dentaria heterophylla Nutt.

Moist woods; frequent, but the plants usually scattered. March-Apr. N. J. to

Tenn.

2. Dentaria laciniata Muhl. :
Moist woods; frequent. Apr.-May. Eastern N. Amer.
The flowers are shown in plate 30A.

170 CONTRIBUTIONS FROM THE NATIONAL, HERBARIUM.

21. SINAPIS L.

Pods glabrous, the beak shorter than the body; upper leaves toothed, or slightly lobed
at the base. . 2.2... cece ec eee cece eee. cece eeeeee --1. S. alba.
Pods very hairy, the heak longer than the body; leaves all pinnately lobed or parted.
2. S. arvensis.
1. Sinapis alba L. WHITE MUSTARD.
Waste ground, Washington, May, 1899 (Steele). Native of Eur.; sometimes culti-
vated and escaping. (Brassica alba Boiss.)
2. Sinapis arvensis L. CHARLOCK.
Collected several times in waste ground about Washington, Native of Eur.; fre-
quently adventive in N. Amer. (Brassica sinapistrum Boiss.; B. arvensis B.S.P.)

22. BRASSICA I.

Upper leaves with clasping auricled bases. Plants glabrous or nearly so.

; 1. B, campestris.
Upper leaves petioled or narrowed at the base.

Pods erect, 15-18 mm. long, on appressed pedicels.................... 2. B. nigra.
Pods ascending, 30-35 mm. long, on spreading or ascending pedicels. .3. B. juncea.

1. Brassica campestris LL. TURNIP.
Old fields and waste ground; frequent. Apr.-May. Native of Eur.; widely cul-
tivated and escaping,
This species includes a number of cultivated forms, any of which may be found as
escapes. B. napus 1. is rape; B. oleracea L, is cabbage.
2. Brassica nigra (L.) Koch. BLACK MUSTARD.
Occasional in waste ground. June-J uly. Native of Eur. and Asia; widely adven-
tive in N, Amer. .
3. Brassica juncea (L.) Coss. INDIAN MUSTARD.
Occasional in fields or waste ground. May-J uly. Native of Asia; widely adven-
tive in N. Amer,

23. RAPHANUS L.
1. Raphanus sativus L. RADISH.

Occasional in waste ground. Native of Asia: common in cultivation and sometimes
escaping.

67, CAPPARIDACEAE. Caper Family.

1. CLEOME L.
1, Cleome spinosa L. SPIDER-FLOWER.
Occasional in waste ground about Washington and Alexandria, July-Oct. Native
of tropical Amer.; common in cultivation and sometimes escaping,

68. SARRACENIACEAE. Pitcher-plant Family.

1. SARRACENIA [,.
1. Sarracenia purpurea L. PitcHER-PLAN’,
Found ina few localities near Bennings and Laurel; very rare. May—June. Eastern
N. Amer.

69. DROSERACEAE. Sundew Family.
1, DROSERA LL. Sunpew.

Leaf blades orbicular, as broad as long.................-..-.-. 1. D. rotundifolia.
Leaf blades spatulate, longer than broad...................2----. 2. D, intermedia,

FLORA OF THE DISTRICT OF COLUMBIA. 171

1. Drosera rotundifolia L.
Bogs near Kenilworth, Suitland, Hyattsville, and Beltsville. July-Aug. Widely
distributed in N. Amer.; also in Eur. and Asia.

2. Drosera intermedia Ilayne.
Bogs near Forest Glen and Beltsville. July-Aug. Eastern N. Amer.; also in Eur.
In both species the leaves are covered with long red gland-tipped hairs which

entrap insects.

70. PODOSTEMACEAE.
1. PODOSTEMUM Michx.

1, Podostemum ceratophyllum Michx. RUFLEWEED.
On rocks in streams; infrequent. Summer. Eastern U.S.

71, CRASSULACEAE. Orpine Family.
1. SEDUM L. STONECROP.

Flowers in one-sided racemes; petals white; leaves entire......- ....1. S. ternatum.

Flowers not in one-sided racemes; petals pink or purple; leaves toothed.
Petals purple, twice as long as the sepals. .....---- 202s eee e reece 2. S. triphyllum.
Petals pink, 3-4 times as long as the sepals.....--------++++++- 3. S. telephioides.

1. Sedum ternatum Michx. THREE-LEAVED STONECROP.
Rocky woods; common. May. Northern states, south to Ga.

2. Sedum triphyllum (Haw.) 8. F. Gray. LIVE-FOR-EVER.
Occasional along roadsides. Native of Asia; common in gardens.

3. Sedum telephioides Michx. WILD LIVE-FOR-EVER.

On rocks along the Potomac. Aug. N. Y. to Ga.

72. PENTHORACEAE. Ditch stonecrop Family.

1. PENTHORUM L

1. Penthorum sedoides L. DitcH STONECROP.
Ditches and wet places; infrequent. July-Aug. Eastern U.S.

73. SAXIFRAGACEAE. Saxifrage Family.

Petals none. Calyx lobes usually 4 and stamens 8; low marsh plant.
1. CHRYSOSPLENIUM.

Petals 5.
Stamens 5, Leaves mostly basal, long-petioled, orbicular.......- 2. HEUCHERA.
Stamens 10.
Stem leaves 2, opposite. ...-.-.-...2 seers eee reece errr 3. MITELLA.
Stem leaves none, the foliage leaves all from base of plant.
Flowers in racemes; ovary l-celled....--.--------+-+++----+> 4, TIARELLA.
Flowers in cymes; ovary 2-celled.....------+--+-------- 5. SAXIFRAGA.
1, CHRYSOSPLENIUM L.
1. Chrysosplenium americanum Schwein, WATER-CARPET.

Springy places: infrequent. Apr.-May. Northern states, south to Ga.

2. HEUCHERA L.

1. Heuchera americana L. ALUM-ROOT.

Rocky woods; frequent. May. N. Y. to N.C.

172 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

3. MITELLA L.
1, Mitella diphylla L. MITERWORT,
Rich woods; above the fall line; infrequent. May-June. Northern states, south
to N.C.
4. TIARELLA L.

1, Tiarella cordifolia L. FALSE MITERWORT.
Rocky woods; rare; Fort Washington (Miss Mary I’, Miller.) May. Eastern U.S.

5. SAXIFRAGA I. Saxrrraae.

1, Saxifraga virginiensis Michx.

Rocky woods; frequent. Apr. Northern states, south to Ga. (Micranthes vir-
gimensis Small.)

The flowers are shown in plate 30.

74. HYDRANGEACEAE. Hydrangea Family.

1. HYDRANGEA IL.

1. Hydrangea arborescens J.. WILD HYDRANGEA.
Rocky woods; frequent. June. Eastern U. 8,

75, ESCALLONIACEAE.

1. ITEA IL.
1. Itea virginica L.
Swamps below the iall line; frequent. June. Southern states, north to N. J.

76. GROSSULARIACEAE. Gooseberry Family.

Plants spineless; flowers in racemes. .......000. 0000000 ee cece cece eee 1. RIBES.
Plants spiny; flowers 1-4 in an umbellate cluster............... 2, GROSSULARIA.
1. RIBES L.

1, Ribes americanum Mill. WILD BLACK CURRANT.

Rich woods; infrequent; Beaver Creek, Blagdens Mill, Brookland. Apr. FEastern
U.S. (R. floridum I, Hér.)

The red currant of cultivation (2. vulgare Lam.; R. rubrum of Ward’s Flora) is
sometimes found in the vicinity of gardens.

2, GROSSULARIA Mill.

1. Grossularia rotundifolia (Michx.) Coville & Britton. WILD GOOSEBERRY,
Rich woods; infrequent; Ammendale, Soldier’s Home Road, Bladensburg. Apr.
Mass. to N.C. in the mountains. (Ribes rotundifolium Michx.)
A low shrub with spines in pairs at the base of the leaf stalks.

77, HAMAMELIDACEAE., Witch-hazel Family.

Flowers with a calyx and 4 petals, in small axillary clusters, appearing in late autumn:
shrubs; leaves with low rounded teeth; branches not winged..1, HAMAMELIS.
Flowers naked, in stalked globular or conic clusters, appearing in spring; trees; leaves

with long acute lobes; branches usually with thick corky wings.
2. LIQUIDAMBAR.

1. HAMAMELIS I.

1. Hamamelis virginiana L. WITCH-HAZEL.
Moist or rocky woods; frequent above the fall line. The flowers appear in autumn
after the leaves have fallen; the fruits remain attached for some time, Eastern U. S.

FLORA OF THE DISTRICT OF COLUMBIA. 173

2, LIQUIDAMBAR L.

1, Liquidambar styracifiua L. SWEET GUM,
Moist woods; frequent. May. Southern states, north to Conn.

78. PLATANACEAE, Sycamore Family.

1, PLATANUS L.

1. Platanus occidentalis L. SYCAMORE,
Rich or moist woods; frequent. May. Eastern U.5.

79. ROSACEAE. Rose Family.

Plants shrubby.
Leaves simple; fruit a follicle or pod with several seeds; plants not prickly.
Follicles inflated; leaves palmately nerved and lobed...... ...1, OPULASTER.
Follicles not inflated; leaves pinnately veined, not lobed.......... 2. SPIRAEA.

Leaves compound; fruit of achenes (several within a fleshy receptacle) or a cluster
of drupelets; plants armed with prickles.

Leaves pinnately compound; fruit of several bony achenes or nutletsinclosed in a
elobular or pear-shaped, somewhat fleshy receptacle; fowers pink, some.
times fading to nearly white..............--.--------2-22-- ee 8. ROSA.

Leaves palmately compound; fruit a globular or oblong cluster of drupelets;
flowers white, sometimes becoming pinkish with age, rarely purplish red.

4, RUBUS.
Plants herbaceous.
Pistil containing more than | ovule; fruit a follicle.
Leaves 2-3-pinnate; flowers small, in a large spicate panicle. .... 5, ARUNCUS.
Leaves 3-foliolate; flowers few, long-peduncled.......... 6, PORTERANTHUS.

Pistil 1-ovuled; fruit an achene, the receptacle sometimes fleshy.
Receptacle enlarged in fruit, juicy or spongy. Plants with runners; leaves
3-foliolate.

Petals white; fruiting receptacle juicy................--..-- 7, FRAGARIA.
Petals yellow; fruiting receptacle spongy.......-.---.----. 8. DUCHESNEA.

Receptacle not enlarged 1n fruit, dry.
Achenes numerous, upon a convex receptacle.
Styles elongating in fruit, jointed and bent near the middle, the upper part
deciduous, the lower persistent as a hook.................. 9, GEUM.
Styles not elongating in fruit and not forming hooks...10. POTENTILLA.
Achenes few, inclosed in an urn-shaped calyx tube.
Petals present, yellow; flowers in long racemes. Margin of the top-shaped
fruiting calyx with hooked prickles...............-- 11. AGRIMONIA.
Petals absent; flowers clustered or spicate.
Flowers in small, nearly sessile clusters; plant a low annual..12,. APHANES,
Flowers in long-peduncled dense heads or spikes; plants perennial.
‘Inflorescence cylindric, white; leaflets 2-5 cm, long.
13. SANGUISORBA.
Inflorescence globular, green; leaflets 8-15 mm, long..14, POTERIUM,

1. OPULASTER Medic.

1, Opulaster opulifolius (L.) Kuntze. NINE-BARK,
Rocky woods; frequent. May. Eastern U.S. (Physocarpus opulifolirs Maxim.;
Neillia opulifolia Benth. & Hook.)

174 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

2. SPIRAEA IL.

Flowers about L cm. wide, on slender pedicels.................- 1. S. prunifolia.
Flowers small, in close clusters.
Leaves thin, glabrous................-..2.22222------222----5-- 2. S. latifolia.
Leaves thick, woolly beneath...................2.2..-.--------- 3. S. tomentosa.

1. Spiraea prunifolia Sieb. & Zucc.
Cultivated and sometimes escaped. Apr. Originally from Japan,
Flowers often double.

2. Spiraea latifolia (Ait.) Borkh. MEADOWSWEET,
Rocky places; Infrequent. July. Northern states, south to Va.
3. Spiraea tomentosa IL. HanrpDHACK.

Low ground; rare; Sligo Creek (O/dys); southwest of Rockville (flitehcock). July,
Northern states, south to Ga,
3. ROSA L. Rose.

Leaflets 3-5; styles coherent in a protruding column. ...........--.. 1. R. setigera.
Leaflets 5—many; styles distinct,
Calyx lobes deeply incised, erect on the fruit, persistent... ......... 2. R. canina.
Calyx lobes deciduous, spreading
Leaflets finely and evenly serrate.................-..2..------ 3. RB. palustris.
Leaflets coarsely serrate.
Infrastipular spines slender, nearly straight............-..-- 4. R. virginiana.
Infrastipular spines stout, with a broad base, curved... .:.... 5. R. rubiginosa.
1. Rosa setigera Michx. CLIMBING ROSE.
Thickets; infrequent. June. Eastern U.S.
2. Rosa canina L. DoG ROSE.

Thickets and roadsides; rare. May. Cultivated in gardens; originally from Eur.;
escaped in the eastern U. 8.
3. Rosa palustris Marsh. SWAMP ROSE.
Borders of swamps and streams; frequent. June. Eastern U.S. (R. carolina ot
authors, not L.)
4, Rosa virginiana Mill.
Borders of swamps; frequent. June. Northern states, south to Md. (CR, lucida
Ehrh.)

5. Rosa rubiginosa L. SWEETBRIER.
Rocky places and open ground; frequent, June. Introduced from Eur.

4. RUBUS L.

Leaves sunple, 3-5-lobed; flowers 3-6 cm. wide, purple-red........-. 1. BR. odoratus.
Leaves compound; flowers white.

Fruit falling away whole from the dry receptacle; petals shorter than the calyx;

plant conspicuously glaucous............-...2---2-.-2-0e- 2. R. occidentalis.

Fruit not separating from the juicy receptacle; petals longer than the calyx; plants
not conspicuously glaucous.

Stems erect or ascending, not prostrate or trailing.
Leaves wedge-shaped at base, pale-velvety beneath; pedicels armed with

prickles........ 22.0.2. 2222 ee eee eee eee 8. R. cuneifolius.
Leaves not conspicuously wedge-shaped nor pale-velvety beneath; pedicels
UNArMed... 6. ee eee nee eee eee 4, R. argutus.

Stems prostrate or trailing.
Stems armed with numerous weak prickles, these not confined to the angles.
5. R. hispidus.
Stems armed with stout prickles on the angles...........-. 6. BR. procumbens.

FLORA OF THE DISTRICT OF COLUMBIA. 175

1, Rubus odoratus L. FLOWERING RASPBERRY.
Thickets; rare; Great Falls (Palmer). June. Northern states, south to Ga.

2. Rubus occidentalis L. BLACK RASPBERRY.
Thickets and fence rows; frequent. May. Eastern U. 8.

3. Rubus cuneifolius Pursh. SAND BLACKBERRY.
Sandy soil; frequent below the fall line. June. Southern states, north to Conn.

4, Rubus argutus Link. TALL BLACKBERRY.

Thickets, fence rows, and old fields; common. May. Mass. to Va. (R. frondosus
of Gray’s Manual; #. villosus of Ward’s Flora.)
5. Rubus hispidus L. . SWAMP BLACKBERRY.
Low woods and swales; frequent below the fall line. June. Eastern states, south
to N.C.
6. Rubus procumbens Muhl. DEWBERRY.
Dry open ground; frequent. May. Eastern U. 8S. (R. canadensis of Ward’s
Flora.)
There are many unidentified specimens of the genus, including probably several
unnamed species.
5. ARUNCUS Adans.
1. Aruncus vulgaris Raf. GOAT’S-BEARD.
Rich woods; frequent. June. Northern states, south to Ga. (A. aruncus Karst. :
Spiraea aruncus L.)

6. PORTERANTRHUS Britton.

1. Porteranthus trifoliatus (L.) Britton. FALse IPECAC.
Rich woods; frequent. May-June. N.Y. to Ga. (Gillenia trifoliata Moench.)

7. FRAGARIA L.

1. Fragaria virginiana Duchesne. WILD STRAWBERRY .
Open ground; frequent. May. Eastern U.S.
The flowers are shown in plate 314A.

8. DUCHESNEA J. E. Smith.

1, Duchesnea indica (Andr.) Focke. FALSE STRAWBERRY,
Waste grassland; infrequent. Southern states, north to Pa,; naturalized from
India. (Fragaria indica Andr.)
The bright red fruit looks exactly like a strawberry, but is not edible.

9. GEUM L. AVENs.

Head of fruit stalked in the bractless calyx. Petals yellow............ 1. G. vernum.
Head of fruit sessile in the calyx; bractlets present.
Petals white.

Receptacle of fruit glabrous................2..-02.--22-.000-- 2. G. virginianum.
Receptacle of fruit hairy.
Basal leaves and lower stem leaves simple or ternate......... 3. G. canadense.
Basal leaves and lower stem leaves pinnate................. 4. G. meyerianum.
Petals yellow.
Petals shorter than the sepals, pale yellow................. Leeeee 5. G. hirsutum.
Petals longer than the sepals, golden yellow..................... 6. G. strictum.

1. Geum vernum (Raf.) Torr. & Gray.
Thickets; infrequent. May. Eastern U.S.
2. Geum virginianum J.
Open woods and thickets; infrequent. June-July. Eastern U. S.

176 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

3. Geum canadense Jacq.
Borders of woods; common. June-July. Eastern U.S. (G. album Gmel.)

4, Geum meyerianum Rydb. ;

Moist ground; infrequent. July-Aug. Northern states, south to Md.
5, Geum hirsutum Mubl.

Woods and banks; rare; Seven Locks (Steele). July. Conn. to Ga.

6. Geum strictum Ait.
Low meadows; frequent. June. Northern states, south to Md.

10. POTENTILLA JI. FIve-FINGER:

Leaves pinnately compound..............-....-.2--2--02e eee 6. P. anserina,
Leaves palmately compound.
Flowers solitary on long axillary peduncles, Plants with prostrate shoots or run-
ners,
Earliest flower from the node above the first well-developed internode.
1, P. pumila.
Earliest flower from the node above the second or third well-developed internode,
2. P. canadensis.
Flowers in cymes.

Leaflets 3.......00. 000000 cee cece eee eee 3. P. monspeliensis.
Leaflets 5-7.
Leaflets green beneath. ... 2.2.0.6... eee eee ee eee eens 4, P, recta.
Leaflets silvery beneath....... Lecce ee eee eee eee eee e ees 5. P. argentea.

1. Potentilla pumila Poir.
Dry ground and old fields; frequent. May. Me. to Md. (P. canadensis of Ward’s
Flora.)
2. Potentilla canadensis L. FIVE-FINGER.
Open ground; frequent. May. Eastern U.S. (P. canadensis simplex of Ward's
Flora. )
8. Potentilla monspeliensis L.
Moist open ground; frequent. July. Nearly throughout N. Amer.; also in Eur.
(P. norvegica 1.)
4, Potentilla recta L.
Fields; rare. June. Northern states, south to Md.; adventive from Eur.
5. Potentilla argentea L. .
Barren places; rare. June. Northern states, south to Md.
6. Potentilla anserina L. SILVER-WEED.
Moist open ground; rare. Northern. states, south to Md. (Argentina anserina
Rydb.)
11. AGRIMONIA L. Aarimony.
Axis of racemes villous. Fruit 6 mm. wide; root not thickened....1. A. gryposepala.
Axis of racemes appressed-pubescent and often glandular, but not villous.
Leaflets glabrous beneath or with a few scattered spreading hairs; fruiting calyx
hemispheric.............. 2.020.200 22. e eee eee eee eee eee ee 2. A. rostellata.
Leaflets pubescent beneath; fruiting calyx topshaped.
Leaflets narrowly lanceolate, the principal ones 9-13 or more; root not tuberous.
3. A. parviflora.
Leaflets oblong or elliptic, mostly 5-7; root tuberous-thickened..4, A. pubescens.
1, Agrimonia gryposepala Wallr.
Dry woods; infrequent. Aug. Northern states, south to Va. (A. hirsuta Bicknell.)

2. Agrimonia rostellata Wallr.
Rocky woods; frequent. Aug. Conn. to Ga. (A. eupatoria of Ward’s Flora.)

FLORA OF THE DISTRICT OF COLUMBIA. 177

3. Agrimonia parviflora Ait.
Sandy fields; frequent. July-Aug. Northern states, south to Ga,
4. Agrimonia pubescens Wallr.
Open woods; frequent. July. Northern states, south to Ga, (A. mollis Britton.)

12, APHANES L.
1. Aphanes arvensis L. LADY’S-MANTLE,
Old fields and waste places; rare. June. Introduced from Eur. (Alchemilla
arvensis Scop.)
13. SANGUISORBA L.
1, Sanguisorba canadensis L. AMERICAN BURNET.
Bogs and swales; infrequent. Aug. Northern states, south to Ga. (Poterium cana-
dense A, Gray.)
14, POTERIUM L.
1, Poterium sanguisorba L. SALAD BURNET,
Fields and waste places; infrequent. May. Northern states, south to Md.
(Sangutsorba minor Scop.)

80. MALACEAE. Apple Family.

Cotoneaster pyracantha (L.) Spach, native of Europe and Asia, was reported by Steele
as an escape from cultivation.

e

Plants usually armed with spines; mature carpels (“‘seeds”’) hard and bony. Flowers
im COrymbs. ...........eeeee eee eee eee cee eet eee eee eeeeees 5. CRATAEGUS.
Plants without spines; mature carpels (‘‘seeds”) papery or leathery.
Flowers in racemes; cells of the mature fruit twice as many as the styles.
4, AMELANCHIER,
Flowers in corymbs or cymes; cells of the mature fruit as many as the styles.
Plants shrubs; cymes compound, branched.........--------+---+++++- 3, ARONIA.
Plants trees; cymes simple.
Flesh of the fruit with grit cells; opening of the receptacle partly closed by a

disklike cushion; flowers white.............-----.0++--eee eee: 1. PYRUS.
Flesh of the fruit without grit cells; opening of the receptacle open; flowers
usually pink or tinged with pink...........-.--------+++e++- 2. MALUS.
1. PYRUS L.
1. Pyrus communis L. PEAR.

Occasional in woods and waste ground. Apr. Native of Eur.; cultivated and often

escaping.
2. MALUS Mill.

Leaves and outer surface of calyx lobes glabrous....-.--------------- 1. M. coronaria.
Leaves and outer-surface of calyx lobes white-woolly............-.-2. M. sylvestris.
1. Malus coronaria (L.) Mill. AMERICAN CRAB APPLE.

Thickets along the Northwest Branch west of Hyattsville; rare. Apr.-May
Eastern U.S. (Pyrus coronaria L.)
2, Malus sylvestris Mill. APPLE.

Occasional in woods and waste ground. Apr.-May. Native of Asia; cultivated
and escaping. (Pyrus malus L; M. malus Britton.)

The cultivated crab apples are derived from the Siberian crab apple, Malus baccata
(L.) Borck., or from hybrids between this and the common apple. The Soulard crab
apple is a hybrid between Malus sylvestris and one of our native species.

69289—19——12

178 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

3. ARONIA Medic. CHOKEBERRY.

Oymes and leaves nearly glabrous. Fruit black.................. 8. A. melanocarpa.
Cymes and lower surface of leaves woolly,
Fruit bright red; calyx lobes very glandular...................... 1. A. arbutifolia.
Fruit purple black; calyx lobes nearly glandless............... 2. A. atropurpurea.

1. Aronia arbutifolia (L.) Ell.
Swamps and wet woods; frequent. May; fr. Sept.-Oct. Eastern U.S. (Pyrus
arbutifolia L. f.)

2. Aronia atropurpurea Britton.

Shaded swamps, eastward; infrequent. May; fr. Aug.—Sept. Eastern N. Amer.,
south to Va. (Pyrus arbutifolia atropurpurea Robinson; P. arbutifolia melanocarpa of
Ward’s Flora.)

3. Aronia melanocarpa (Michx.) Britton.
Region of Fourmile Run; perhaps elsewhere. May. Eastern N. Amer. (Pyrus
melanocarpa Willd.)

4. AMELANCHIER Medic. SHapsusn. SERVICEBERRY. JUNEBERRY.

Leaves short-pointed; hypanthium (the combined calyx tube, receptacle, and ovary)
small, 2.5-3 mm. in diameter, bell-shaped, not constricted below on the young
fruit; sepals broad, oblong-triangular, obtuse or abruptly acute or short-pointed,
reflexed from the base at time of falling of petals; petals 10-14 mm. long; tree
OF SHTUD ... 2... eee eee eee eee e cence cee ceeeeeees 1. A. canadensis.

Leaves rounded at the tip; hypanthium 3-5 mm. in diameter; sepals narrow, triangu-
lar or lanceolate, acute, erect or recurved from the middle at time of falling of
petals; petals 7-9 mm. long; shrubs.

Hypanthium saucer-shaped, constricted below on the very young fruit; sepals
recurved from the middle at time of falling of petals; top of the ovary woolly,
at least when young; leaves oval, the veins 7-11 (average 8 or 9) pairs; teeth
of average leaves 20-28 (32) on each side; stems 0.3-1.2 meters high, growing in
colonies from rhizome-like bases.................cccceceeeeee 2. A. stolonifera,

Hypanthium bell-shaped, not constricted below; sepals mostly erect; top of the
ovary glabrous, rarely slightly woolly; leaves oblong, the veins 10-15 (average
11-13) pairs; teeth finer (20) 25-40 (45) on each side; stem 1.2-8 meters high,
forming alder-like clumps...........2...-..0.0.0000eeeeee- 3. A. oblongifolia.

1. Amelanchier canadensis (L.) Medic.

Dry open woodlands; frequent. Apr.; fr. June. Eastern U. 8. (A. canadensis
botryapium of Gray’s Manual.)

2, Amelanchier stolonifera Wiegand.

Rocks at Great Falls; edge of Hyattsville Swamp. Apr. Eastern N. Amer.
(A. spicata of Britt. & Brown, Illustr. Fl.)

3. Amelanchier oblongifolia (Torr. & Gray) Roemer.

Swamps; occasional eastward. Apr. Me. to S. C. (A. canadensis oblongifolia
Torr. & Gray; A. intermedia of Britt. & Brown, Illustr. F1.)

Wiegand has identified as A. laevis Wiegand specimens from Bladensburg and
Fourmile Run collected by Steele, and adds that they show affinity with A. cana-
densis.

5. CRATAEGUS L. Hawrnorn. Rep Haw.

Leaves conspicuously triangular-cordate, glabrous.............. 1. C. phaenopyrum.
Leaves not triangular-cordate, glabrous or pubescent.
Petioles about 1 mm. long................... 2. 0c cece eee ce eeees 2. C. uniflora.

FLORA OF THE DISTRICT OF COLUMBIA. 179

Petioles 15 mm. long or longer.
Leaves wedge-shaped, broadest at or above the middle.
Leaves broadest toward the apex; petioles without stalked glands.

; . 3. C. crus-galli.
Leaves broadest at the middle; petioles with stalked glands.

Leaves, corymbs, and fruit pubescent.....-..-..-------- 4, C. intricata.
Leaves, corymbs, and fruit glabrous.......---------+++++++- 5. C. straminea.
Leaves broadest at the base.
Leaves 1.5-6.5 cm. long and wide; calyx lobes usually entire. .6. C. pruinosa.
Leaves 2.5-10 em. long and wide; calyx lobes usually toothed...7. C. coccinea.

1. Crataegus phaenopyrum (L. f.) Medic. WASHINGTON THORN.

Fields and roadsides; known from a few localities. May. Md. to Ga. and west-
ward. (C. cordata Ait.)

2. Crataegus uniflora Muenchh.

Woods along the upper Potomac; occasional. May. Eastern U.S. (C. parvifolia
Ait.; C. tomentosa of Gray’s Manual.)

3. Crataegus crus-galli L. CocKSsPuR.

Sandy soil; frequent. May. [Eastern N. Amer.

4, Crataegus intricata Lange.

Congress Heights and Hunting Creek; rare. May. Eastern U. 8. (C. coccinea
of Gray’s Manual, and of Ward’s Flora, in part; probably C. tomentosa of Brereton’s
Prodromus. )

5. Crataegus straminea Beadle.

High Island (Steele). Eastern U.S. (C. apposita Sarg.)
6. Crataegus pruinosa (Wendl.) Koch.

Near Laurel (J. B. S. Norton). May. Eastern U.S.

7. Crataegus coccinea L.

High Island (Sudworth); without locality (Vasey). Eastern N. Amer. (C. pedi-
cellata Sarg.)

Crataequs monogyna Jacq. was reported from near Alexandria by Ward (as:'C. oxya-
cantha). Native of Eur. and Asia; cultivated and sometimes escaping.

Crataegus canbyi Sarg., C. cuneiformis (Marsh.) Eggleston, and C. boyntoni Beadle
may occur in our area and should be looked for.

81, AMYGDALACEAE. Almond Family.

Ovary and fruit pubescent; stone pitted.....-.--------++-+++: 1. AMYGDALUS.
Ovary and fruit glabrous; stone smooth or nearly SO.....--------+-++- 2, PRUNUS.

1. AMYGDALUS L.
1. Amygdalus persica L. PEACH.
Occasionally found growing spontaneously in waste land. Apr. Native of Asia.

(Prunus persica Stokes.)
2. PRUNUS L.

Flowers in racemes, the axis longer than the pedicels.
Leaves thick, oblong, crenate-serrulate, the teeth incurved.......-- 1, P. serotina.
Leaves thin, obovate, sharply serrate, the teeth somewhat spreading.
2. P. virginiana.
Flowers in umbels or in very short racemes.
Flowers large, the petals 8-16 mm. long.
Teeth of leaves acuminate, not glandular; fruit oblong-globose, about 2 cm. in
diameter.....cccccce ccc c cect cece c cee n ewer e ec eeceeseneees 3. P. americana.
Teeth of leaves obtusish, some or all glandular; fruit depressed-globose, about
1 cm. in diameter.

180 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Leaves glabrous; inner scales of flower bud appressed; fruit sour. .4. P. cerasus.
Leaves pubescent beneath, at least on the veins; inner scales of flower bud

subherbaceous, spreading; fruit sweet...............2.....- 5. P. avium.
lowers small, the petals 4-6 mm. long.
Leaves orbicular-ovate......00.0000 00000 cece ccc cece eee eee 6. P. mahaleb.
Leaves elliptic to oblong.

Leaves elliptic, serrulate to the base, not paler beneath... .... 7. P. angustifolia,

Leaves spatulate-oblong, not serrulate along the cuneate base, pale beneath.
8. P. cuneata.
1. Prunus serotina Ehrh. WILD BLACK CHERRY,

Rich woods; frequent. May. Eastern U.S. (Padus virginiana of Britt. & Brown,
Illustr. FI.)
2. Prunus virginiana L. CHOKE CHERRY.
Thickets and river banks; rare. May. Northern states, south to Ga. (Padus
virginiana Mill.)
3. Prunus americana Marsh. WILD PLUM.
Thickets and fence rows; frequent. Apr. Southern states, north to Conn. *

4. Prunus cerasus L. Sour CHERRY.
Occasionally escaped from cultivation, Apr. Native of the Old World.

5. Prunus avium L. SWEET CHERRY.
Occasionally escaped from cultivation, along fence rows, Apr. Native of the Old

World.

6. Prunus mahaleb L. MAHALEB,
Roadsides and thickets; infrequent. May. Originally from Eur.

7. Prunus angustifolia Marsh. CHICKASAW PLUM,
Thickets; frequent. Apr. Southern states, north to Del. (2, chicasa Michx.)

8. Prunus cuneata Raf.
Thickets in sandy soil; infrequent. May. Northern states, south to N, (.

82, CAESALPINIACEAE. Senna Family.

Leaves simple, entire; flowers reddish purple; pods winged, Trees... 1. CERCIS.
Leaves compound, of numerous leaflets; flowers yellow or green; pods not winged.
Plants trees, armed with spines; flowers small, inconspicuous, greenish.
2. GLEDITSIA,
Plants herbaceous, unarmed; flowers mostly large, showy, bright yellow.
Plants perennial, glabrous or nearly so; leaflets large, mostly 3.5-5 cm, long; pods
jointed... 2. ccc eee eee 3. CASSIA.
Plants annual; leaflets small, mostly less than 2 em. long; pods not jointed.

4. CHAMAECRISTA,
1. CERCIS JL.
1. Cercis canadensis L. Reppup.

Woods; common, Apr. Eastern U.S.
Known also as Judas tree.
2. GLEDITSIA L,
1. Gleditsia triacanthos L. HONEY Locust,
Woods; common, May.’ Eastern states, south to Ga.
Often planted as a shade tree; remarkable for the:large branched thorns usually
found along the trunk; pods broad and flat, often 80-45 em, long.

8. CASSIA L. WILD SENNA.

Joints of the pod as long as broad or longer; gland on the petiole usually club-shaped:
stipules very narrowly linear..................2..---2----- ‘....1. C. marilandica.
Joints of the pod broader than long; glands conic or cylindric; stipules linear-lan-
ceolate. 2... cee cc ce cece cee eee eeee 2. C. medsgeri.

FLORA OF THE DISTRICT OF COLUMBIA. 181

1, Cassia marilandica L. ;
Thickets, woods, or low ground; frequent. July-Aug. Eastern U. 8.

2. Cassia medsgeri Shafer.
Two specimens from our region seen, neither with definite locality. Eastern U.S.

4, CHAMAECRISTA Moench.

Flowers 5-8 mm. wide; pedicels shorter than the sepals, stout........1. C. nictitans.
Flowers 25-40 mm. wide; pedicels mostly longer than the sepals, very slender.
2, C. fasciculata.
1. Chamaecrista nictitans (L.) Moench. SENSITIVE PEA.
Dry woods and fields; common. July—Oct. Eastern U.S. (Cassia nictitans L.)
In both our species the leaves are ‘‘sensitive,’’ folding together when touched.

2. Chamaecrista fasciculata (Michx.) Greene. PARTRIDGE PEA.
Dry soil; common. July-Oct. Eastern U.S. (Cassia chamaecrista of many Ameri-
can authors, probably not of Linnaeus.)

83. FABACEAE. Pea Family.

Leaves all or mostly with 4 or more leaflets,
Plants trees, armed withspines...........-....0.00..0-05-0-.-20200004. 10, ROBINIA.
Plants wholly herbaceous, not spiny.

Leaflets digitate, all attached at the end of the petiole. Perennial with large blue
flowers......-.2.22..2.---4- bee e eee eee eee cece eee 3. LUPINUS.

Leaflets pinnately arranged, part or all of them attached along the rachis.
Leaves evenly pinnate, without a leaflet at the end of the rachis, the rachis

usually ending in a tendril; flowers blue or purple.

Style with a tuft of hairs at the top; leaflets small, rarely 8 mm, wide, or
in one species large and toothed, thin and not very prominently veined.

15, VICIA.
Style hairy on the inner side; leaflets large, mostly over 1 cm, wide, thick,
entire, prominently veined ................-2-.-+-2--- 16. LATHYRUS.

Leaves odd-pinnate, with a leaflet at the end of the rachis.
Leaflets 5 or 7 (sometimes 3 in the uppermost leaves); stems twining, Plants
perennial, with tuber-bearing roots; flowers brownish purple; leaflets
10 mm. wide or larger...........-.--------.-2-------- 18. GLYCINE.
Leaflets more than 7 in all or most of the leaves, usually much more numer-
ous; stems erect.
Stems with short, closely appressed hairs; pods not flattened; flowers

greenish yellow... ........ 0.022 c cece eee eee eee 11. ASTRAGALUS.
Stems with long spreading hairs; pods flat; flowers yellowish and purple.
9. CRACCA.”

Leaves with 1 or 3 leaflets. .
Leaves all with 1 leaflet, or simple. Flowers yellow.
Plants perennial, tall, somewhat shrubby, nearly glabrous; pods flat.
Flowers 12 mm. long, nearly sessile..............--++------ 4. GENISTA.
Flowers 25 mm. long, the pedicels 6-10 mm. long............5, CYTISUS.
Plants annual, low, herbaceous, very hairy; pods inflated....2. CROTALARIA.
Leaves, at least most of them, with 3 leaflets.
Leaflets finely toothed (teeth almost obsolete in the common red clover, Trifolium
pratense). Flowers usually less than 1 cm. long; pods 1-few-seeded.
Flowers in long slender racemes, white or yellow. Plants sweet-scented;
pods small, not curved or coiled...............-.-+4-- 7. MELILOTUS.,

182 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Flowers in dense heads or umbels or in short, thick, very dense spikes.
Pods curved or coiled; flowers yellow or bluish purple...... 6. MEDICAGO.
Pods not curved or coiled; flowers variously colored...... 8. TRIFOLIUM.

Leaflets entire or sometimes lobed, never toothed.

Plants with woody stems.

Plants erect, the stems acutely angled; leaflets rarely over 1 cm. long.

5. CYTISUS.
Plants climbing, the stems obtusely angled; leaflets mostly 10 cm. long or
larger...... wee cee ee cee ee eee eee eee cece eee eeeeeee 24, PUERARIA.

Plants herbaceous.
Pods of 2 or more joints (the joints evident even in the ovary of the flower);
stipules sometimes bearing long yellow bristles.
Flowers yellow; stipules with long yellow bristles; leaflets small, usually

less than 8 mm, wide......-..........2------ 12. STYLOSANTHES.
Flowers purple or purplish; stipules never bristly; leaflets usually much
more than 1 cm. wide..,...............---.00 eee 13, MEIBOMIA.

Pods not jointed; stipules never with yellow bristles.
Flowers on axillary 1 or 2-flowered peduncles; corolla about 5 cm. long,
pale blue. Pods flat.................-22.2.222--.- 17, CLITORIA.
Flowers variously arranged, the peduncles when axillary bearing more
than 2 flowers; corolla less than 2 cm. long, usually much smaller.
Stems erect, never twining.
Pods 1-seeded; flowers purple or yellowish white; stipules very
small, brown wee eee cee eee eee cece eee eee eee 14, LESPEDEZA-
Pods with more than one seed; flowers never purple; stipules often
large and green.

Leaflets densely and finely hairy beneath, the veins coarse and
prominent beneath; petals only slightly longer than the calyx,
yellow; pods flat.......-....-........004- 21. DOLICHOLUS.

Leaflets glabrous or nearly so, the veins slender, not prominent;
petals much longer than the calyx; pods inflated.

1. BAPTISIA.
Stems climbing, twining.
Flowers in heads or umbels; leaflets sometimes lobed. Flowers pink
or White.......-------------ee eee ee eee 2. STROPHOSTYLES.
Flowers in racemes; leaflets not lobed.

Leaflets very obtuse or rounded at the apex. Flowers purple or
purplish; calyx with a small bract at the base. .20, GALACTIA.

Leaflets very acute.

Stems with numerous reflexed brown hairs. [Flowers white to
purple; pods finely hairy..................... 19. FALCATA.

Stems never with reflexed hairs; flowers purple; pods glabrous.
22. PHASEOLUS.

1. BAPTISIA Vent. Wup INpDIGOo.

Flowers blue; stipules longer than the petioles, leaflike, persistent. .... 1. B. australis.
Flowers yellow; stipules minute, deciduous...................------- 2. B. tinctoria.
1. Baptisia australis (L.) R. Br.

Low ground along the upper Potomac, abundant in some localities. May-June.
Southern states, north to Pa.
2. Baptisia tinctoria (L.) R. Br.

Dry woods; common. June-July. Hastern U.S.

FLORA OF THE DISTRICT OF COLUMBIA. 1838

2. CROTALARIA L.

1. Crotalaria sagittalis L. RAtTTLEBOX,
Dry open soil; frequent. July-Aug. Eastern U. S. to Mex.

3. LUPINUS L.

1. Lupinus perennis L. WILD LUPINE.
Dry or wet, sandy soil; frequent. Apr._May. Eastern U. 8.
4. GENISTA L.
1. Genista tinctoria L. DyYEWEED.

Waste ground at Fourteenth and Decatur Streets (Steele). Native of Eur. and Asia;
sparingly naturalized in N. Amer.
5. CYTISUS L.

1. Cytisus scoparius (L.) Link. Broom.
Established in Rock Creek Park and a few other localities in the same region.
Apr.June. Native of Eur.; naturalized in many parts of N. Amer.

6. MEDICAGO L.

Flowers violet or blue; leaflets more than twice as long as broad....-.... 1, M. sativa.
Flowers yellow; leaflets less than twice as long as broad, often as broad as long.
2. M. lupulina.

Medicago arabica (L.) Huds. (M. maculata Sibth.) has been reported from waste
ground in Washington.

1. Medicago sativa L. ALFALFA,

Occasional in waste ground. June-July. Native of Asia; widely cultivated for
fodder, and often escaping.
2. Medicago lupulina L. BLAcK MEDIC.

Fields and waste ground; frequent. May-July. Native of Eur. and Asia; widely
naturalized in N. Amer. .

%. MELILOTUS Mill.

Flowers white; standard petal slightly longer than the wing petals......- 1. M. alba,
Flowers bright yellow; standard about as long as the wings......---- 2. M. officinalis.
1, Melilotus alba Desv. WHITE SWEET CLOVER.

Waste ground; abundant. May-Aug. Native of Eur. and Asia; widely natural.
ized in N. Amer.
2, Melilotus officinalis (L.) Lam. YELLOW SWEET CLOVER.
Waste ground; frequent. May-Aug. Native of Eur. and Asia; widely naturalized
in N. Amer.
8. TRIFOLIUM L. CLOVER.
Flowers yellow.
Terminal leaflet sessile, like the lateral ones; heads of flowers 12-20 mm. long;
stipules linear or nearly 80.......------+-+-seeee reece ee seeeee 1, T. agrarium.
Terminal leaflet slender-stalkea; heads of flowers all or nearly all less than 12 mm
long; stipules ovate.
Flowers 20-40 in each head; standard petal conspicuously furrowed.
2. T. procumbens.
Flowers about 10 in each head; standard only slightly furrowed...3. T. dubium.

Flowers white, red, or purple.
Heads of flowers much longer than broad, long-stalked. Calyx teeth long-hairy ;

plants very hairy.
Corolla crimson, equaling or longer than the calyx lobes; leaflets as long as broad
or nearly 80...--.-. 2.022 eee eee e eee eee eee tenet nerccee 4. T. incarnatum

184 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Corolla whitish, shorter than the calyx lobes; leaflets more than twice as long as

LS) Xe 5. T. arvense.
Heads of flowers as broad as long or nearly so.
Flowers sessile in the head; heads all or mostly sessile............. 6. T. pratense.

Flowers stalked; heads all long-stalked.
Heads of flowers about 3 cm. in diameter; plants hairy; leaflets much longer
than broad..... 2... eee cee eee cece cece cena 7. T. reflexum.
Heads of flowers 1.5-2.5 cm. in diameter; plants nearly glabrous; leaflets nearly
or quite as broad as long.

Stems erect or ascending, not rooting...............2...... 8. T. hybridum.
Stems Creeping, rooting at the joints............. eee eens ....9, T, repens.
1. Trifolium agrarium L. Hop CLOVER.

Dry fields and waste ground; common. June-Aug. Native of Eur.; widely
naturalized in N, Amer,
2, Trifolium procumbens L.
Dry fields and waste ground; common, May-June. Native of Eur.; widely
naturalized in N, Amer.
3. Trifolium dubium Sibth.
Dry fields and waste ground; occasional. May-June, Native of Eur.; widely
naturalized in N, Amer,
4, Trifolium incarnatum L. - CRIMSON CLOVER.
Roadsides and old fields; occasional, but not persisting like other adventive species.
May-July. Native of Eur.; sometimes cultivated and escaping.
5. Trifolium arvense L. RABBIT-FOOT CLOVER.
Dry fields; common. May-July. Native of Eur. and Asia; widely naturalized
in N. Amer.
6. Trifolium pratense L. RED CLOVER.
Fields and meadows; abundant. May-Aug. Native of Eur. and Asia; widely
cultivated and naturalized in N. Amer.
White-flowered plants are sometimes found. Specimens of this species have been
reported from our region as 7. medium 1.

7. Trifolium reflexum L. BUFFALO CLOVER.
Low ground along the upper Potomac; rare. May-June, Eastern U. §.
8. Trifolium hybridum L, ALSIKE CLOVER,

Meadows and waste ground; common, May-Sept. Native of Eur.; widely
naturalized in N, Amer.
9. Trifolium repens L. WHITE CLOVER,
Fields, meadows, and waste ground; abundant. Flowering throughout the sum-
mer. Native of Eur.; widely naturalized in N. Amer.

Lotus corniculatus L, bird’s-foot trefoil, was collected along the railroad near II
Street bridge, Aug., 1915 (J. B. 8. Norton). Native of Eur.; occasionally adventive
in N. Amer.

Amorpha fruticosa L., false indigo, was found as an escape from cultivation in Poto-
mac Park, May, 1898 (Steele). The species is native farther south and west.

9, CRACCA L.
1, Cracca virginiana L. GOAT’S-RUE,

Dry fields and woods; common. May-June. Fastern U.S. (Tephrosia virginiana
Pers.)
The flowers are shown in plate 31.

FLORA OF THE DISTRICT OF COLUMBIA. “185

10. ROBINIA L.
1. Robinia pseudo-acacia L. BLACK LOCUST.
Abundant; perhaps naturalized. May. Pa. to Iowa and Ga.
A tree is shown in plate 33.
Several other species of the genus are frequent in cultivation.

11, ASTRAGALUS L.

1. Astragalus carolinianus L. . MILK VETCH.
Low ground along the upper Potomac. June-July. Northern states, south to Ga.
(A. canadensis L.)

12. STYLOSANTHES Swartz. PENCIL FLOWER.

Leaflets oblong-linear to oblanceolate, the larger ones 3 cm. long or longer, usually
very acute; bracts subtending the flowers entire; plants very bristly.

1. S. biflora.
Leaflets oval or elliptic, mostly less than 2 cm. long, usually rounded or obtuse at the
apex; bracts 3-parted; plants only slightly bristly......-....----- 2. S. riparia.

1. Stylosanthes biflora (L.) B.S.P.
Dry soil; common. July-Sept. Eastern U.S. (S. elatior Swartz.)

2. Stylosanthes riparia Kearney.
Dry soil; occasional. June-Aug. Pa. to Ala.

13, MEIBOMIA Heist. Tick TREFOIL.

Stipules large, green, ovate or triangular, persistent.
Stems trailing.
Flowers purple; leaflets orbicular or nearly so; joints of the pod 3-5.
4, M. michauzii.
Flowers whitish; leaflets broadly ovate; joints of the pod 2 or 3..5, M. ochroleuca.

Stems erect.

Leaflets glabrous or nearly so, very acute......-..--..---++------ 6. M, bracteosa.
Leaflets hairy, very obtuse..........--..2-.0-- eee eee ees ....7. M, canescens.
Stipules small; brown, narrowly linear or subulate, often deciduous.

Pod borne on a stalk many times longer than the calyx, not lobed on the upper
margin, very deeply lobed on the lower margin, the joints 1-4, Stems usually
erect; plants nearly glabrous.

Flowering stems naked, rising from the base of the sterile leafy stems.
1, M. nudiflora.
Flowering stems leafy.
Leaves scattered along the stems; leaflets obtuse........... 2. M. pauciflora.
Leaves crowded at the top of the stem below the panicle; leaflets taper-pointed.
; 3. M. grandiflora.

Pod sessile, or borne on a short stalk only 2 or 3 times as long as the calyx, lobed

on both margins but much more deeply so below than above.
Leaflets small, most of them less than 2.5 cm. long, rounded at the apex; joints
of the pod 2 or 3.
Plants glabrous or nearly so; petioles about as long as the lateral leaflets.
14. M. marylandica.
Plants copiously hairy; petioles usually much shorter than the lateral leaflets.
15. M. obtusa.
Leaflets larger, most of them more than 3 cm. long, usually much larger; joints
of the pod often more numerous.
Stems and leaves glabrous or nearly so. Joints of the pod 4-6.
Leaflets lanceolate or oblong, all or most of them less than 2 cm. wide, green
beneath. .......... 2 eee eee te ener eee 8. M. paniculata.

186° CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Leaflets broadly ovate or oval, most of them well over 2 em. wide, glaucous
beneath....... 2... eee eee ccc eee eet e eee ee eeee 9. M. laevigata.
Stems and leaves conspicuously hairy.
Leaflets densely velvety beneath, the hairs spreading..... 10. M. viridiflora.
Leaflets not velvety beneath, the hairs appressed.
Joints of the pod triangular, with a conspicuous angle on the lower side;
pods conspicuously stalked..................0-0.00ee 11. M. dillenii.
Joints of the pod oval, rounded on the lower side; pods sessile or nearly so.
Racemes of flowers dense, with numerous large bracts just before flower-
ing; corolla 8-12 mm. long; joints of the pod usually 4-6.
12. M. canadensis.
Racemes very loosely flowered, the bracts very small; corolla about 5mm.
long; joints of the pod usually 2..................... 13. M. rigida.

1. Meibomia nudiflora (L.) Kuntze.

Dry woods; frequent. July-Sept. Eastern N. Amer. (Desmodium nudiflorum
DC.)

Plants with white flowers are found occasionally.
2. Meibomia pauciflora (Nutt.) Kuntze.

A single specimen seen, collected near Pierce’s Mill, Sept., 1878, by Ward. Eastern
U.S. (Desmodium pauciflorum DC.)
3. Meibomia grandiflora (Walt.) Kuntze.

Woods; occasional. June-July. Eastern N. Amer. (Desmodium acuminatum
DC.; D. grandiflorum DC.)
4. Meibomia michauxii Vail.

Dry woods; occasional. Aug.Sept. Eastern U. 8. (Desmodium rotundifolium
DC.; D. rotundifolium glabratum A. Gray.)
5. Meibomia ochroleuca (M. A. Curtis) Kuntze.

Mount Hamilton, Oct., 1882 (Ward). N.J. to Ga. and Mo. (Desmodium ochroleu-
cum M. A. Curtis.)
6. Meibomia bracteosa (Michx.) Kuntze.

Woods along the upper Potomac; occasional. Aug.—Sept. Eastern U. S. (Des-
modium bracteosum Michx.)
7. Meibomia canescens (L.) Kuntze.

Thickets along the Potomac and Rock Creek; occasional. July-Sept. Eastern
U.S. (Desmodium canescens DC.)
8. Meibomia paniculata (L.) Kuntze.

Woods and thickets; frequent. Aug.—Sept. Eastern U.S. (Desmodium panicu-
latum DC.)
9. Meibomia laevigata (Nutt.) Kuntze.

Dry woods; occasional. Aug.-Sept. Eastern U.S. (Desmodium laevigatum DC.)
10. Meibomia viridiflora (L.) Kuntze.

Woods and thickets; occasional. Aug.-Sept. Eastern U. 8. (Desmodium viridi-
florum Beck.)
11. Meibomia dillenii (Darl.) Kuntze.

Woods and thickets; common. Aug.-Sept. Eastern U. S. (Desmodium dillenti
Darl.)
12. Meibomia canadensis (L.) Kuntze.

Low ground along the Potomac below Washington. Aug.—Sept. Eastern N. Amer.
(Desmodium canadense DC.)
13. Meibomia rigida (Ell.) Kuntze.

Dry soil; rare. Aug.—Sept. Eastern U.S. (Desmodium rigidum DC.)

FLORA OF THE DISTRICT OF COLUMBIA. 187

14. Meibomia marylandica (L.) Kuntze.

Dry woods and thickets; frequent. Aug.—Sept. Eastern U. 8. ( Desmodium
marylandicum Boott.)
15. Meibomia obtusa (Muhl.) Vail.

Dry soil; frequent. Aug.Sept. Eastern U. 8. (Desmodium obtusum DC.; D.
ciliare DC.)

Specimens of this species have been reported erroneously from ourjregion as JM.
arenicola Vail.

14, LESPEDEZA Michx. BusH CLOVER.

Plants annual; stipules ovate or lanceolate; calyx lobes ovate or oval, very obtuse.
Flowers pink or purple........- bocce cence nc eee cee enenerepecceacees 1. L. striata.

Plants perennial; stipules narrowly linear, bristle-like, long-tapering; calyx lobes
narrow, very acute.

Flowers all alike, perfect, in dense spikes or heads; corolla about as long as the
calyx, whitish or yellowish, sometimes with a purple spot on the standard; pod
not longer than the calyx lobes.

Peduncles longer than the leaves; leaflets oval to nearly orbicular, less than twice
as long as broad, loosely hairy beneath; flowers spreading in the spikes.

2. L. hirta.

Peduncles shorter than the leaves; leaflets oblong or elliptic, more than twice as

long as broad, closely silky-hairy beneath; flowers erect or ascending in the

spikes........ 2-22-22 e eee e eee cece ce eee eee eee e tenes 3. L. capitata.

Flowers of 2 kinds, some of them petaliferous, in racemes or panicles, the petals
purple, much longer than the calyx, the others mostly without petals, fertile,
in small sessile clusters or mixed with the others; pods much longer than the
calyx lobes.

Peduncles all or nearly all shorter than the leaves, or the flower clusters sessile.
Leaflets densely woolly or velvety beneath, oval to oblong. Flower clusters

all sessile or nearly SO.....-.-...- 2222-2 ee eee eee eee eee ee eee 4. L. stuvei.
Leaflets glabrous beneath or with closely appressed hairs.
Leaflets oval or oblong; flower clusters often stalked.......- 5. L. frutescens.

Leaflets linear to linear-oblong; flower clusters all sessile or nearly so.
6. L. virginica.
Peduncles, at least most of them, longer than the leaves.
Stems with spreading hairs.
Stems prostrate or trailing; peduncles long and slender, nearly all of them

longer than the leaves......--.---.--------+++-+-+-++- 7. L. procumbens.
Stems erect; peduncles short and stout, often shorter than the leaves.
8. L. nuttallii.
Stems glabrous or with closely appressed hairs.
Stems erect; stipules mostly 5-8 mm. long.....-..------- .....9. L. violacea-
Stems prostrate or trailing; stipules 2-5 mm. long............. 10. L. repens.
1. Lespedeza striata (Thunb.) Hook. & Arn. JAPAN CLOVER.

Dry woods and fields; oftenabundant. Aug—Sept. Native of eastern Asia; exten-
sively naturalized in eastern N. Amer.

2. Lespedeza hirta (L.) Hornem.

Dry fields and woods; frequent. Aug.-Oct. Eastern U.S.

Lespedeza hirta oblongifolia Britton has been collected in our region, and one collec-
tion has been reported incorrectly as L. angustifolia (Pursh) Ell. Its inflorescence
resembles that of L. hirta, but the leaflets are narrower and the pubescence appressed
The plant has not been found in fruit and it has been surmised that it is a hybrid
between L. hirta and L. angustifolia. If this is not the case the form is well worthy
of specific rank.

188 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

8. Lespedeza capitata Michx.
Dry woods and fields; common. Aug.-Sept. Eastern U.S.
4. Lespedeza stuvei Nut.
Dry fields and woods; frequent. Aug.-Sept. Eastern U.S.
5. Lespedeza frutescens (LL.) Ell.
Dry woods and fields: frequent. Aug.Sept. Eastern U.S. (ZL. stuvei of Ward’s
Flora, in part.)
6. Lespedeza virginica (1..) Britton.
Dry woods and fields; common. Aug.-Oct. Eastern U.S. (L. reticulata anqusti-
folia of Ward’s Flora.)
Lespedeza sieboldit Miq., a Japanese species, with large flowers, was collected along
a roadside near Riverdale, Sept., 1905 (Touse). Escaped from cultivation.
7. Lespedeza procumbens Michx.
Dry woods and fields; frequent. Aug.-Sept. Eastern U. 8,
8. Lespedeza nuttallii Darl.
Dry woods; occasional. Aug.-~Sept. Eastern U.S.
9. Lespedeza violacea (L.) Pers.
Dry woods and fields; frequent. Aug.-Sept. Eastern U.S
10. Lespedeza repens (L.) Bartr.
Dry woods and fields; common. July-Sept. Eastern U.S

15. VICIA L. Vercn.

Leaflets 1-3 pairs, most of them 2 cm. wide or larger. Flowers large. sessile or nearly
ge,

so in the axils; leaflets and stipules toothed.................. 1. V. narbonensis.
Leaflets more than 3 pairs in all or most of the leaves, less than 1 cm, wide,
Flowers sessile or nearly so in the axils of the leaves............ 2. V. angustifolia.
Flowers in long-stalked racemes,
Flowers 1-6 in each raceme, 4mm, long orsmaller.............. 3. V. tetrasperma.

Flowers more than 6 in most of the racemes, usually much more numerous, 7 mm.
long or larger.

Plants very hairy; flowers 1.5 cm. long or larger, violet; pods about | cm. wide,

4. V. villosa,

Plants glabrous or nearly so; flowers 1 cm. long or shorter, bluish white; pods

5-7 mm. wide....... 2... 2c eee 5. V. caroliniana.

1. Vicia narbonensis IL. FRENCH VETCH.

Well established in fields near Chevy Chase Lake. May-June. Native of Eur.:.
cultivated and sometimes escaping.

Vicia faba ¥.., the broad bean, with large entire leaflets, was collected in waste
ground, Hyattsville, June, 1907 (Mrs. FE. 8, Steele). Native of Asia and Africa:
much grown for food in Eur., and rarely in N. Amer.

2. Vicia angustifolia L.

Fields and waste ground; frequent. Apr.—June. Native of Eur.; widely natur-
alized in N. Amer,

Often reported from our region as V. sativa L., a species so far not found here.
3. Vicia tetrasperma (L.) Moench.

Fields and waste ground; occasional. May-July. Native of Eur. and Asia:
naturalized in eastern N. Amer,

Vicia hirsuta (L.) Koch, with hairy 2-seeded pods, was collected near the Long
Bridge, June, 1898 (Steele), Native of Eur. and Asia; occasionally naturalized in
N. Amer.

FLORA OF THE DISTRICT OF COLUMBIA. 189

4. Vicia villosa Roth. HAIRY VETCH.
Fields, roadsides, and waste ground; frequent, and thoroughly established. May-
Sept. Native of Eur. and Asia; sometimes cultivated and escaping.
5. Vicia caroliniana Walt.
Woods and thickets; frequent. Apr-May. Eastern N. Amer.

16. LATHYRUS L. WItp rea.

Leaflets mostly 2 or 3. pairs; flowers 2-8 in the raceme.....-...- 1. L. myrtifolius.
Leaflets 4-6 pairs in most of the leaves; flowers usually 10-25 in the raceme,
2. L. venosus.
Lathyrus latifolius L., the everlasting pea, with only one pair of leaflets, was col-
lected along a roadside near Soldiers’ Home, June, 1897 (Kearney). Native of Eur.;
often cultivated for ornament and sometimes escaping.

1. Lathyrus myrtifolius Muhl.

Marshes along the Eastern Branch. July. Northern states, south to N.C. (ZL,
palustris of Ward’s Flora.)
2. Lathyrus venosus Muhl.

Low ground along the upper Potomac; frequent. May. Eastern N. Amer.

17. CLITORIA L.
1. Clitoria mariana L. BUTTERFLY PEA.
Dry or moist ground; frequent. June-Aug. Southern states, north to N. J.

18. GLYCINE L.
1. Glycine apios L. POTATO PEA.
Moist ground; occasional. July-Sept. Eastern N. Amer. (Apios tuberosa Moench;
A. apios MacM.)
19. FALCATA Gmel. HoG PEANUT.

Leaflets thin, mostly 1.3-5 cm. long; calyx about 4 mm. long; bracts small.
1. F. comosa.
Leaflets firm, mostly 5-10 cm. long; calyx about 6 mm, long; bracts large.
2. F. pitcheri.
1. Falcata comosa (L.) Kuntze.
Low thickets; frequent. Aug.-Sept. Eastern N. Amer. (Amphicarpa monoica
EI.)
2. Falcata pitcheri (Torr. & Gray) Kuntze.
Low thickets; frequent. Aug.—Sept. Northern states, south to Va. (Amphicarpa
pitchert Torr. & Gray.)
These two species are separated by no definite character, and by none that would
be considered important in related groups of the family. Probably both are forms
of one polymorphous species.

20. GALACTIA P. Br. MILK PEA.

Stems glabrous or nearly so; leaflets glabrous beneath or with a few appressed hairs;
‘pods only slightly hairy .............-..-+++-22+-22e2e2e eee: 1. G. regularis.
Stems with short soft spreading hairs; leaflets soft-downy beneath; pods very hairy.
2. G. volubilis.
1. Galactia regularis (L.) B.S.P.
Near Berwyn; reported from Suitland and Chain Bridge; rare. July—Aug. East-
ern U.S.
2. Galactia volubilis (L.) Britton.
Dry woods and fields; frequent. July-Sept. Eastern U.S. (G@. mollis Nutt.)

190 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

21. DOLICHOLUS Medic.

1. Dolicholus erectus (Walt.) Vail.
Dry soil; rare. July-Aug. Southern states, north to Del. (Rhynchosia tomentosa
ot Ward’s Flora; R. erecta DC.)

‘ 22, PHASEOLUS IL.
1. Phaseolus polystachyus (L.) B.S.P. WILD BEAN.
Low thickets along the Potomac; rare. Aug.—Sept. Eastern U.S. (P. perennis
Walt.)

The common cultivated bean, Phaseolus vulgaris L., is sometimes found on garbage

dumps.
23. STROPHOSTYLES Ell. Witp BEAN.

Leaflets all entire; pods 3.5-5 cm. long, 4 mm. wide or narrower..... 1. S. umbellata.
Leaflets, at least some of them, usually shallowly lobed; pods mostly 5-7 cm. long,
5-7 mm. Wide...... 2.2... eee eee ee eee eee eee eee Lecce cece eee 2. S. helvola.

1, Strophostyles umbellata (Muhl.) Britton.
Dry or moist soil; frequent. July-Aug. Eastern U.S.
2. Strophostyles helvola (L.) Britton.
Dry or moist soil; frequent. Aug.-Sept. Eastern N. Amer. (Phaseolus helvolus L.)

24. PUERARIA DO.

1, Pueraria thunbergiana (Sieb. & Zucc.) Benth. Kupbzu VINE.
Becoming established in several localities. Native of China; often cultivated for
ornament.
It has been planted in the Zoological Park and elsewhere, and spreads rapidly.

Vigna sinensis (L.) Endl., the cow pea, is found occasionally in waste ground.
Native of Asia; widely cultivated and sometimes escaping, but not persisting in our
climate. (V. catjang Walp.)

Dolichos lablab L., the hyacinth bean, is sometimes found in waste ground. Native
of Asia; often cultivated for ornament and sometimes escaping, but not persisting
with us.

84. GERANIACEAE. Geranium Family.

Leaves pinnate, with distinct leaflet ts; beaks of the fruit bodies spirally coiled at
maturity... 0... cece ec e eee eee eee cece cece eee eeeneenees 1. ERODIUM.
Leaves palmately lobed; beaks of the fruit bodies merely recurved at maturity.

2, GERANIUM.
1. ERODIUM L.

1. Erodium cicutarium (L.) L’Hér. ALFILERIA,
Old fields and waste ground; occasional. Apr.—June. Native of Eur. and Asia;
widely naturalized in N. Amer.

2. GERANIUM LL. CraANnr’s-BILL.

Plants perennial, with thick rootstocks; petals 12-17 mm. long..... 1. G. maculatum,
Plants annual, with fibrous roots; petals 8 mm. long or shorter.
Peduncles much longer than the leaves; body of the fruit smooth and glabrous,
Petals bright purple; seeds pitted.....................00- 2. G. columbinum.,
Peduncles mostly shorter than the leaves; body of the fruit hairy or wrinkled.
Body of the fruit glabrous, wrinkled. Petals deep purple; seeds smooth.

. 3. G. molle.
Body of the fruit hairy, not wrinkled.

Petals deep purple; seeds pitted............2..2..222.-2200-- 4. G. dissectum.

FLORA OF THE DISTRICT OF COLUMBIA. 191

Petals pale purple to nearly white; seeds smooth or reticulate.
Seeds smooth; flowers on 2-flowered peduncles, loosely arranged.
5. G. pusillum.
Seeds reticulate; flowers in dense clusters. ..............6. G. carolinianum.

1, Geranium maculatum L.

Woods; common. Apr.-June. Eastern U.S.
2. Geranium columbinum L.

Fields; occasional. May-June. Native of Eur. and Asia; naturalized in the
eastern U.S.
3. Geranium molle L.

Fields; College Park. Apr.May. Native of Eur.; naturalized in eastern N.
Amer.
4. Geranium dissectum L.

College Park, May, 1916 (J. B. S. Norton). Native of Eur.; occasionally adventive
in N. Amer.
5. Geranium pusillum L.

Fields about Bladensburg. May-June. Native of Eur.; adventive in N. Amer.
6. Geranium carolinianum L.

Dry fields; common. Apr.May. Widely distributed in N. Amer.

After flowering the plants become tinged with red, presenting a characteristic
appearance.

85. OXALIDACEAE. Wood-sorrel Family.

Flowers purple; plants stemless, the leaves all basal..........------- 1. IONOXALIS.
Flowers yellow; plants with leafy stems..............-.+--+-+-+ 2. XANTHOXALIS.

1. IONOXALIS Small.

1. Ionoxalis violacea (L.) Small. VIOLET WOOD-SORREL.
Dry woods or fields; common. May-June. Widely distributed in the U. S.
(Oxalis violacea L.)
Often known as sheep sorrel; the leaves have an agreeable acid flavor.

2. XANTHOXALIS Small. YELLOW WOOD-SORREL.

Petals about 15 mm. long, sometimes larger; stems mostly simple, erect, 30 cm. high
or taller. Hairs of the stems and petioles spreading......-..----- 1. X. grandis.
Petals 8-12 mm. long; stems often much branched, sometimes prostrate.
Pedicels loosely hairy; plants tall, usually more than 30 cm. high; leaflets mostly
9-3 CM. Wide..... eee ee cee cee cece cece cece seer eeneee 2. X. cymosa.
Pedicels with appressed hairs; plants usually less than 30 cm. high; leaflets usually
less than 1.5 cm. wide.
Stems covered with fine, closely appressed hairs........-.-.------ 3. X. stricta.
Stems nearly glabrous, or with spreading hairs.
Capsules densely and finely appressed-hairy; stems extensively creeping.
4. X. corniculata.
Capsules glabrous below or nearly throughout, finely hairy at the top; stems
usually not creeping..........---.--- 2. eee eee eee eee e ees 5. X. filipes.

1. Xanthoxalis grandis Small.

Moist woods; known definitely only from Plummers Island. May-June. Eastern
U.S. (Oxalis grandis Small.)
2. Xanthoxalis cymosa Small.

Mostly in moist or shaded soil; common. May-Sept. Eastern U. 8. (Oxahs
cymosa Small; O. corniculata stricta of Ward’s Flora, in part.)

192 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

3, Xanthoxalis stricta (L.) Small.

Fields or woods; common. May-Aug. Widely distributed in N. Amer. (Oxalis
stricta L.; O. corniculaia stricta Sav.)
4. Xanthoxalis corniculata (L.) Small.

Waste ground, Washington; rare. June-Sept. Native of tropical regions gener-
ally; adventive in the eastern U. S. (Oxalis corniculata L.; O. repens of Gray’s
Manual.)

5. Xanthoxalis filipes Small.
Woods; common. May-Aug. Md.toGa, (Ovxalis filipes Small.)

86. LINACEAE. Flax Family.
1. LINUM L. Fax.

Linum usitatissimum L., cultivated flax, with blue flowers, is sometimes found in
waste ground.

Leaves mostly opposite; stems striate-angled; plants of wet soil. Capsules depressed.
1. L, striatum.
Leaves all, except the very lowest, alternate; stems not angled; plants mostly of dry
soil.
Capsules pointed at the top, as long as broad.................. 2. L, floridanum.
Capsules depressed, flat or broadly rounded at the top, broader than long.
Flowering branches erect, rigid; leaves narrowly lanceolate, dull or pale green;

sepals in fruit usually with numerous glandular teeth. ....... 3. L. medium,
Flowering branches ascending or spreading, flexuous; leaves oblong, deep green;
sepals in fruit usually without teeth...............-.... 4. L. virginianum.

1, Linum striatum Walt.

Swamps or low ground; frequent. July-Sept. Eastern U. S. (Cathartolinum
striatum Small.)
2. Linum floridanum (Planch.) Trel.

Dry soil; occasional. July-Sept. Eastern U. 8. (Cathartolinum floridanum
Small; L, virginianum of Ward’s Flora, in part.)
3. Linum medium (Planch.) Britton.

Dry soil; frequent. June-Aug. Eastern U.S. (JL. virginianum of Ward’s Flora,
in part; Cathartolinum medium Small.)
4, Linum virginianum L.

Dry or moist woods; Rock Creek Park, Paint Branch, and along the Patuxent near
Laurel. June-July. Eastern U. 8. (Cathartolinum virginianum Reichenb.)

A specimen of Kallstroemia parviflora Norton, of the family Zygophyllaceae, was
collected in the Department of Agriculture Grounds in 1895 (G. H. Hicks), Native
of the southwestern U.S.

87. RUTACEAE. Rue Family.

Zanthoxylum americanum Mill., prickly ash, was reported by Ward from Pierce’s
Mill, but doubtless only as an escape from cultivation; native of the eastern U. 8.
A plant of Ruta graveolens 1.., rue, was found in Potomac Park in 1902 (@. H. Shull);
native of Eur.

1. PTELEA L.
1. Ptelea trifoliata L. Hop TREE,

Woods along the Potomac; frequent. May-June. Eastern U.S.

Known also as wafer ash,

FLORA OF THE DISTRICT OF COLUMBIA. 193

88. SIMAROUBACEAE. Quassia Family.

1. AILANTHUS Desf.

1. Ailanthus altissima (Mill.) Swingle. TREE OF HEAVEN.
Waste ground; frequent. June-July. Native of China; often cultivated and
becoming naturalized. (A. glandulosa Desf.)

89. POLYGALACEAE. Milkwort Family.
1. POLYGALA L. Mirxwort.

Flowers orange-yellow, in a dense head. Plants perennial or biennial ...1. P. lutea.
Flowers not yellow.
Plants perennial. Flowers in a spike or raceme.

Flowers white; leaves lanceolate..............-----------eeeeeeeee 2. P. senega.
Flowers rose-purple; leaves, at least the lower ones, obovate or narrowly wedge-
obovate... cece ec eee eee eee eee eee ete n erence eeeee 8. P. polygama.

Plants annual.
Leaves all or partly whorled.
Flowers in long cylindric racemes 2-3 mm. thick.

Leaves all whorled........----- 2-2-2222 e cece eee ee eee eee 4. P. verticillata.
Leaves except the lowest alternate........--..----------+++ 5. P. ambigua.
Flowers in dense oblong racemes 8-12 mm. thick..........----- 6. P. cruciata.

Leaves all alternate.
Stems with nearly all leaves reduced to scales. Flowers rose-purple.
11. P. incarnata.

Stems leafy.
Flowers rose-purple.
Bracts of the racemes persistent after the fall of the flowers. Racemes 10-12
mm. thick .... 2.2.22. eee cece cece cece eee e eee eeeeeee 8. P. curtissii.

Bracts of the racemes deciduous.
Wings 4.5-6 mm. long; pedicels much shorter than the pod.
7. P. viridescens.
Wings 3-3.5 mm. long; pedicels as long as the pod ....- 9. P. mariana.
Flowers greenish or nearly white.
Racemes thick-oblong; bracts of the racemes soon deciduous.
7. P. viridescens.
Racemes conical; bracts persisting after the fall of the flowers.
10. P. nuttallii.

1. Polygala lutea L. WILD BACHELOR’S-BUTTON.
Sandy swamps; vicinity of Laurel; near Suitland. June-Oct. Coastal Plain,
Long Isl. to La.

2. Polygala senega L. SENECA SNAKEROOT,

Wooded hillsides; seemingly confined to the Piedmont Region. May-June.
Northern states, south to N. C.

The leaves vary considerably, ranging from lanceolate to ovate. The larger-leaved
form has been described as var. latifolia Torr. & Gray, but the forms so intergrade here
that it is impossible to draw a line of separation. The rootstock is listed as an official
drug in the U. S. Pharmacopeea.

8. Polygala polygama Walt.

Dry soil; Great Falls and Broadwater; apparently rare. June-July. Eastern N.
Amer.

Bears numerous small cleistogamous flowers on underground branches.

69289—19——_13

194 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

4. Polygala verticillata L.
Dry soil, fields and meadows; frequent. July-Oct. Eastern N. Amer.
Our form has whitish flowers,
5. Polygala ambigua Nutt.
Dry fields and open ground; frequent. July-Oct. Northern states, south to Ga.
Flowers almost always purplish in our form.
6. Polygala cruciata L.
Sandy swamps and bogs; infrequent; Powder Mill bogs; Brightwood; reported
also from Lakeland. July-Sept. Eastern U. S.
7. Polygala viridescens L.
Fields and open ground; frequent. June—-Oct. Northern states, south to N. C.
(P. sanguinea L.; P. purpurea Nutt.)
The greenish white and purplish forms were originally described as distinct species,
the name P. sanguinea being applied to the latter.

8. Polygala curtissii A. Gray.

Open woods or sandy fields, seemingly where the water table is high; apparently
confined to the Coastal Plain. July-Oct. Md. to Ga.

This species was described from an abnormal form collected near Alexandria by
A. H. Curtiss. The normal form was given the varietal name pycnostachys by Gray
and published by Knowlton. This is possibly the plant referred to by Brereton as
P. purpurea.

9. Polygala mariana Mill.

Sandy fields, Coastal Plain; frequent. July-Oct. Southern states, north to N. J.
(P. fastigiata Nutt.).

10. Polygala nuttallii Torr. & Gray.

Sandy soil on the Coastal Plain; infrequent. J uly-Sept. Eastern U. 8S. (P.
sanguinea Nutt.)

11. Polygala incarnata L.

Sandy fields and pine woods; frequent. July-Sept. Eastern U. 8.

Probably P. setacea of Brereton’s Prodromus, as this is the only “‘aphyllos” plant
of the genus in this vicinity.

Polygala paucifolia Willd., the flowering wintergreen or fringed polygala, is listed
in Brereton’s Prodromus, but has not been reported since. It isa dainty plant with
1-4 handsome pink or rose-purple flowers, 1.4-2 cm. long, in the axils of the upper
leaves.

90. EUPHORBIACEAE. Spurge Family.

Juice not milky; flowers not in a calyx-like involucre. Annual plants; leaves

alternate. ;
Ovules 2 in each cell. Leaves entire, 2-ranked; flowers in small axillary clusters,
apetalous; stamens 3............-.200.0 0202 eee ee eee eee 1. PHYLLANTHUS.

Ovule 1 in each cell.
Pubescence scaly or of branched hairs; petals and stamens 5; stamens incurved

in bud; ovary l-celled.........2.0.0.....0.222--00000- 2. CROTONOPSIS.
Pubescence neither scaly nor of branched hairs; flowers apetalous; stamens erect
in bud; ovary 3-celled.......0..00.00 00.000 cece cece eee 3. ACALYPHA.

Juice milky; inflorescence (a cyathium) resembling a small perfect flower, consisting
of several staminate flowers, each composed of a single stamen, and a central
pistillate flower, all inclosed in a calyx-like involucre with 1-5 glands between
its 5 lobes.

FLORA OF THE DISTRICT OF COLUMBIA. 195

Glands of the involucre without petal-like appendages; cyathia in umbels or cymes
topping a well-developed stem.
Plants annual, hairy; stipules glandlike; cyathia in cymose clusters, with 1 or

rarely 4 glands. ............- 2-0 eee eee ee ee eee eee eee eee 6. POINSETTIA.
Plants perennials or winter annuals, glabrous; stipules none; cyathia in 3-many-
rayed umbels, with 4 glands...............--0-0-eeee eee 7. TITHYMALUS.

Glands with petal-like appendages, or the cyathia borne in the forks of the stem
near the ground.
Plants deep-rooted perennials; stipules minute........... 5. TITHYMALOPSIS.
Plants annuals; stipules triangular or awl-shaped............- 4. CHAMAESYCE.
1. PHYLLANTHUS L.
1. Phyllanthus carolinensis Walt.
Frequent in low sandy soil. June-Oct. Eastern U.S. to Centr. Amer.
2. CROTONOPSIS Michx.

1. Crotonopsis linearis Michx.
Reported from near Berwyn. Dry sandy soil, eastern and southern U. 8.

Mercurialis annua L. was collected by Steele on the Department of Agriculture
grounds in 1916, the station since destroyed. Adventive from Eur.

38. ACALYPHA LL. THREE-SEEDED MERCURY.

The bracts are sometimes reduced or wanting in both our species; such forms and
occasional intermediates are difficult to place. Variations with spreading rather
than appressed pubescence occur here.

Leaves ovate, long-petioled; bracts deeply lobed, not prominently ciliate; branches

ASCENdING...-.-- 2-2 eee ee eee eee ee eee eee eee eee eee eneees 1. A. virginica.
Leaves linear to lanceolate, short-petioled; bracts dentate to cleft, usually conspicu-
ously ciliate; lower branches spreading, long and slender.........2. A. gracilens.

1. Acalypha virginica L.

Common in fields, gardens, and open places generally. June-Oct. Eastern N.
Amer.
2. Acalypha gracilens A. Gray. :

Common in open places, usually in drier situations than the preceding, but the
two often together. June-Oct. Eastern and southern U. 8.

Ricinus communis L., the castor-oil plant, is found occasionally in waste ground,
escaping from cultivation and often seeding itself year to year, but not established.

4. CHAMAESYCE &. F. Gray.

Capsules pubescent; seeds less than 1 mm. long, violet gray to reddish. “Plant pros-

trate; stem puberulent to hairy......-..---.------+se-- eee ee eee 1. C. maculata.
Capsules glabrous; seeds larger, black, often with a whitish coating.

Stem hirsute, prostrate or spreading; middle leaves about twice as long as wide;

seed faces smooth or slightly wrinkled...........--------+---- 2. C. rafinesqui.

Stem with scattered hairs or glabrous, erect or ascending; middle leaves about 3

times as long as wide; seed faces with broken transverse ridges. ..3. C. preslii.

1. Chamaesyce maculata (L.) Small. MILK PURSLANE.
Common on dry walks and open ground. June-Nov. Eastern U.S. (Euphorbia
maculata L.)

2. Chamaesyce rafinesqui (Greene) Small.
Reported from Great Falls and Marshall Hall (as Euphorbia hirsuta (Torr.) Wieg.
Pa. and northward. (Euphorbia rafinesqui Greene.)

196 CONTRIBUTIO.°S FROM THE NATIONAL HERBARIUM.

3. Chamaesyce preslii (Guss.) Arth.

Common in cultivated fields and open waste places. May-Oct. Eastern N. Amer.
(Euphorbia hypericifolia of Ward’s Flora; E. preslii Guss. )

The whole plant turns crimson in autumn.

Dichrophyllum marginatum (Pursh) Klotzsch & Garcke, snow-on-the-mountain, is
sometimes found around gardens where it has been cultivated. Native of the western
U.S. (Euphorbia marginata Pursh.)

5. TITHYMALOPSIS Klotzsch & Garcke.

The species of this genus, while generally distinct, often hybridize when they occur
together, and it is probable that the great variety of occasional intermediates, even
between such distinct species as 7. corollata and T. tpecacuanhae, have arisen in this
way. The flowers are often replaced by a cauliflower-like gall. All the species vary
greatly in amount of pubescence, red color of stem and leaves, and form of leaf and
appendages,

Main stem well developed, longer than the umbel ; plants flowering in summer.
Leaves bright green, not much paler on the lower side, sessile or nearly so.
5. T. corollata.
Leaves dark green above, paler on the lower side, generally short-petioled, spreading
or drooping. Plant more pubescent, especially at the nodes. .4. T. paniculata.
Main stem nearly always shorter than the umbel, often subterranean; plants flowering
in spring or early summer.
Appendages of the involucral glands none or about half the width of the gland,
greenish. Plant entirely glabrous or very rarely with a few hairs at the nodes;
main stem below ground, the first flowers appearing at the surface.

1. T. ipecacuanhae.
Appendages conspicuous, petal-like.

Plants with a main stem 10-30 cm. long, the stems erect, often hairy at the nodes;
leaves lanceolate to ovate or, if oblong, broadest below the middle, darker on
the upper side; first flowers May to June................. 8. T. zinniiflora.

Plants branching from near the ground or, if with a longer main stem, then ascend-
ing, not conspicuously more hairy at the nodes; leaves of many forms, not
much darker above; first flowers April to May............ 2. T. marylandica.

1. Tithymalopsis ipecacuanhae (L.) Small. WILD IPECAC.
Common in open places in the sandy soils east of Washington. Apr.-May. Eastern
U.S. (Euphorbia ipecacuanhae L.)
Very variable in leaf form and color.

2. Tithymalopsis marylandica (Greene) Small.

Rare in sandy land at Sunnyside and Seat Pleasant, but more frequent north of
our range toward Baltimore. May-July. (Euphorbia arundelana Bartlett; E. mary -
landica Greene.)

A great many forms intermediate between 7 tpecacuanhae and T’. corollata are
included under this name, and it is possible that they all originated from crosses of
those species, as both occur with 7. marylandica in nearly every place where it has
been found.

Tithymalopsis mercurialina (Michx.) Small has been reported from our region but
probably erroneously. (Euphorbia mercurialina Michx.)

8. Tithymalopsis zinniifiora Small.

Rare in sandy land; College Park. June. Southeastern U. 8.
4. Tithymalopsis paniculata (Ell.) Small.

Occasional, generally in sandy land; Plummers Island and Bladensburg. South-
eastern U.S. (Euphorbia paniculata Ell.)

Specimens collected by Dewey at Glen Carlyn and by Knowlton at Laurel are
intermediate between this and 7’. corollata.

FLORA OF THE DISTRICT OF COLUMBIA. 197

6. Tithymalopsis corollata (L.) Klotzsch & Garcke. FLOWERING SPURGE.
Common in somewhat dry open places, roadsides, and fields. July-Oct. Eastern
N. Amer. (Euphorbia corollata L.)
Variable in form of leaf, inflorescence, and appendages, and in amount of pubes-

cence.
6. POINSETTIA Graham.

The poinsettia (P. pulcherrima Graham), with brilliant red upper leaves, is a well-
known houseplant, especially popular at Christmas time.

1. Poinsettia dentata (Michx.) Small.
Open places; Seven Locks and near Plummers Island. July-Sept. Pa. to Tex.
(Euphorbia dentata Michx.)

7. TITHYMALUS Adans.

The name spurge is applied generally to all the plants of this and even related
genera, but more strictly belongs to T. lathyrus (L.) Hill, known also as caper spurge
and mole plant, a stout glaucous plant with linear-lanceolate leaves, sometimes
cultivated in gardens.

Leaves serrulate; glands transversely oval; seeds lenticular, smooth or faintly reticu
late. Winter annual; umbel 3-rayed; capsule warty...-.-.----- 1. T. obtusatus.

Leaves entire; glands crescent-shaped; seeds ovoid.
Leaves obovate; umbel 3-rayed; seeds pitted; winter annual....2. T. commutatus.
Leaves linear; umbel many-rayed; seeds smooth; perennial by buds on horizontal
TOOLS... 2-22 eee ee eee eee eee terete eens ter enerrscsess 3. T. cyparissias.

1. Tithymalus obtusatus (Pursh) Klotzsch & Garcke.

Frequent locally in moist open woods. March-June. Eastern and southern U. 8S.
(Euphorbia obtusata Pursh; E. dictyosperma of Ward’s Flora.) :
2. Tithymalus commutatus (Engelm.) Klotzsch & Garcke.

Occasional in rich moist land, chiefly in woods, along the upper Potomac. March-
June. Eastern and southern U.S. (Euphorbia commutata Engelm.)

3. Tithymalus cyparissias (L.) Hill. CYPRESS SPURGE.

One colony on the campus at College Park; also found along the railroad near
Laurel. May. Cultivated from Eur. and frequently naturalized in the northeastern
states. (Euphorbia cyparissias L.)

Seeds rarely in the United States but commonly at College Park.

91. CALLITRICHACEAE. Water starwort Family.
1. CALLITRICHE L. WATER STARWORT.

Plants forming low tufts on moist soil; leaves uniform in shape, 3-nerved, crowded;

fruit pedunculate. Bracts none.......--------++2+++-e-seere tress 1. C, austini.
Plants aquatic or sometimes growing on mud; leaves 1-nerved; fruit sessile.

Fruit with rather fugacious bracts at the base; emersed and submersed leaves

unlike.
Fruit oval, flat on the face, longer than the styles.....------------ 2. C. palustris.
Fruit obovate, plano-convex, shorter than the styles.....-..-- 3. C. heterophylla.
Fruit without bracts; all leaves submersed, linear.....-.-------- 4. C. autumnalis.

1. Callitriche austini Engelm.

Occasional in damp shaded places. Fr. May-June. Eastern U.S.
2. Callitriche palustris L.

In shallow, usually running water. Fr. May—Aug. Cosmopolitan. (C,verna L.)
3. Callitriche heterophylla Pursh.

In shallow water; Woodside and Hunting Creek. Fr. May-Aug. Eastern U.S.

oe]

198 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

4. Callitriche autumnalis L.
In shallow water; Great Falls, Md., May, 1899 (Steele). Widely distributed in N,
Amer., Eur., and Asia. (C. bifida Morong.)

92. LIMNANTHACEAE.
1. FLOERKEA Willd.

1. Floerkea proserpinacoides Willd. FALSE MERMAID.
Low wet soil; High Island, below Dead Run, and Plummers Island. Apr.-May.
Eastern U. S.

93. ANACARDIACEAE. Sumag Family.

The smoke tree, Cotinus coggyria Scop., is cultivated for its attractive feathery
fruiting panicles and highly colored autumn foliage.

Fruit whitish, glabrous or sparsely pubescent; stone striate; small trees, shrubs,
or climbing vines, poisonous to the touch. Leaflets 3-13.
1. TOXICODENDRON.
Fruit reddish or purplish, densely pubescent; stone smooth; shrubs or small trees, not
poisonous.
Flowers in dense terminal panicles, appearing after the leaves; leaflets more than 3.

2. RHUS.
Flowers in clustered spikes, appearing before the leaves; leaflets 3.

3. SCHMALTZIA.
1. TOXICODENDRON Mill.

Leaflets 7-13; tall shrubs, sometimes treelike...........000.000.........1. 7. vernix,
Leaflets 3; low shrubs, suberect and scrambling, or climbing to considerable heights.
2. T. radicans.

1. Toxicodendron vernix (L.) Kuntze. Porson suMAC.
Swamps; frequent. July. Eastern U.S. (Rhus venenata DC.; R. vernix L.)
This is the most poisonous species.

2. Toxicodendron radicans (L.) Kuntze. Porson tvy,
Woods or open fields; common. May-June. Eastern U. S. (Rhus radicans L.)
The typical form is a low erect pubescent plant. Very often, however, the plants

are climbing and glabrate. The latter form is T. pubescens Mill. (Rhus toxicoden-

dron L.; T. toxicodendron Britton.)

2. RHUS L. Sumac.

Rachis of the leaf wing-margined..............0...00-0-000000---0.... 1. BR. copallina.
Rachis of the leaf not winged.
Foliage and twigs velvety-pubescent.........0.....0000-000ce0e- eee. 2. R. hirta.
Foliage and twigs glabrous..............0..00.0ccecceeceeeee cee. 3. R. glabra.
1. Rhus copallina L. DwarrF suMAC.

Woods or open fields, preferring dry situations; common. July. Eastern U.S.

A shrub, usually 1-2 meters high; leaflets glabrous on the upper surface. Sometimes
known as black sumac.
2. Rhus hirta (L.) Sudw. STAGHORN SUMAC.

Dry rocky soil; frequent. June. Eastern N. Amer. (R. typhina L.)

This species has orange-colored wood and is ordinarily a shrub 2-5 meters high.
8..Bhus glabra L. WHITE suMAC.

Dry soil; common. July. Eastern N. Amer.

A shrub 1-3 meters high. Knownalso as scarlet or smooth sumac. The leaves, like
those of other species, are sometimes used for tanning.

FLORA OF THE DISTRICT OF COLUMBIA. 199

38. SCHMALTZIA Desv.

1. Schmaltzia crenata (Mill.) Greene. FRAGRANT SUMAC.
Rocky woods; rare; Broadwater. Apr. Eastern N. Amer. (Rhus aromatica Ait.;
R. canadensis Marsh.)
A shrub with red drupes.

94, AQUIFOLIACEAE. Holly Family.
1. ILEX L. Hotty.

Leaves thick, persistent, spiny-toothed; medium-sized tree. Fruit globose, red,

7 mm. or more in diameter.......--------++---rerer rte 1. I. opaca.

Leaves neither persistent nor spiny-toothed; shrubs.

Staminate flowers solitary or in pairs. Peduncles 1-2 cm. long; fertile flowers
solitary, short-stalked; fruit orange-red, sometimes yellow; nutlets smooth;
leaves oval or oblong, about 5 cm. long, sparsely serrate, villous beneath on the
VOINS. 0. cece eee e cece cece cece eee reese eter ee seeeneseccnsseesss 2. I. laevigata.

Staminate flowers clustered or in cymes.

Fertile flowers nearly sessile; fruit red (rarely yellow); nutlets smooth; leaves
oval or obovate, acute or acuminate, sharply serrulate, downy beneath on
the veins....-.----ceeeece eect eee e cette ec receetresss te 3. I. verticillata.

Fertile flowers stalked, the stalk about 5 mm. long; fruit red; nutlets ribbed;
leaves obovate or spatulate-oblong, crenate-serrate, commonly obtuse.

4, I. decidua.
1. Ilex opaca Ait. AMERICAN HOLLY.
Low woods. May-June; fr. Aug.—Sept. Eastern U. S.
2. Ilex laevigata (Pursh) A. Gray. SMOOTH WINTERBERRY.
Low woods. May-June; fr. Aug.—Sept. Northeastern U. §8., south to Ga.
8, Ilex verticillata (L.) A. Gray. BLACK ALDER. WINTERBERRY.
Swamps and low woods. June; fr. Aug. Eastern U. S.
4. Ilex decidua Walt. DeEcIDUOUS HOLLY.

Low woods. May-June; fr. Aug.-Sept. Southeastern U.S§., north to Md.
95. CELASTRACEAE. Bittersweet Family.

Leaves opposite; erect shrubs; flowers in axillary cymes..-.-.------ 1. EVONYMUS.
Leaves alternate; climbing shrub; flowers in terminal compound racemes.
2. CELASTRUS.
1. EVONYMUS L.

Leaves ovate-lanceolate, 8 cm. long or less; flowers greenish pink or yellow; capsule
SE aaa 1. E. americanus.

Leaves ovate-oblong, 10 cm. long or more; flowers purple; capsule smooth.
2. E. atropurpureus.

1. Euonymus americanus L. STRAWBERRY BUSH.
Low woods; frequent. May. Eastern U. 8. (BE. americanus obovatus of Ward’s

Flora.)

g, Euonymus atropurpureus Jacq. WaHoo.

Low woods and river basins; along the Potomac above Georgetown. May-June.

Eastern U. 8.
2, CELASTRUS L.

1. Celastrus scandens L. BITTERSWEET.
Low woods and river basins; infrequent. May. Eastern N. Amer.

200 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

96. STAPHYLEACEAE. Bladdernut Family,

1. STAPHYLEA JI.
1. Staphylea trifolia L, BLADDERNUT,
Moist woods. Apr.May. Eastern U. §.

Several species of Aesculus, of the Aesculaceae, are cultivated in parks and along
streets. They are trees with palmately compound leaves of 5-9 leaflets, conspicuous
panicles of white, yellow, or pink flowers, and large smooth seeds. The most common
is A. hippocastanum L., the horse chestnut.

97, ACERACEAE. Maple Family.

Leaves simple; plants with perfect flowers; twigs reddish............... 1. ACER.
Leaves pinnately compound; plants dioecious; twigs bright green...... 2. RULAC.

1. ACER L. Map te.

Several exotic species of maples are cultivated as shade trees, the more common
being: A. pseudo-platanus L., the sycamore maple, a large tree with drooping racemes,
woolly ovaries, and deeply 3-5-lobed leaves; A. platanoides L., the N orway maple, a
large tree with flowers in corymbs, and shallowly 5-7-lobed leaves ; A. tartaricum L.,
a shrub with roundish, scarcely lobed leaves; A. campestre L., a small tree with
small 3-5-lobed leaves, 3.5~7.5 cm. long.

Lobes of the leaves meeting in an evenly rounded curve; flowers appearing with the
leaves, green, hanging from long stalks, these often 5 cm, long; fruit maturing
in summer; body of each fruit distinctly less than twice the length of its sear.

1. A. saccharum.

Lobes of the leaves meeting at an angle; flowers appearing before the leaves, red or
yellow, in close clusters on the twigs, the stalks of the pistillate flowers, however,
elongating with the development of the fruit; fruit maturing in May or late April;
body of each fruit twice the length of its scar or more.

Leaf sinuses (the space between the lobes) intruded less than half the length of the
lateral lobes, approximately right-angled, the sides nearly straight; minute
petals present in the flower, in addition to the calyx lobes; fruit without hairi-
ness from the first, 1.5-2.5 cm. long when ripe................... 2. A. rubrum.

Leaf sinuses intruded more than half the length of the lateral lobes, the sides much
curved outward before meeting at the angle; flower with calyx lobes only, no
petals; fruit woolly when young, retaining a scattered pubescence until matu-
rity, 5-7 cm. long when 1 8. A. saccharinum.

1. Acer saccharum Marsh. SUGAR MAPLE.
Rich woods along the Potomac; infrequent. May. Northern states and south-

ward in the mountains. (A. saccharinum Wang.)

2. Acer rubrum L, RED MAPLE.
Swamps and moist woods; common. Feb.-Apr. Eastern U. 8.
Also called swamp maple.

8. Acer saccharinum L,. SILVER MAPLE.
River banks; frequent. Jan.-March. Eastern U. 8. (A. dasycarpum Ehbrh,)
One of the earliest trees to flower in the spring.

2. RULAC Adans.
1. Bulac negundo (L.) Hitche. BoxeELDER.

Low moist woods; common. Apr. Eastern U, 8. (Acer negundo L.; Negundo
aceroides Moench.)

FLORA OF THE CISTRICT OF COLUMBIA. 201

Cardiospermum halicacabum L., balloon vine, of the family Sapindaceae, has been
collected about Eckington. A native of the tropics, sometimes cultivated for orna-
ment northward, and escaping but not persisting. It is a slender annual vine, dis-
tinguished by its bladdery balloon-like fruits.

98, IMPATIENTACEAE. Touch-me-not Family.
1. IMPATIENS L.

Flowers pale yellow, slightly spotted with brownish red; stems pale green.

1. I. pallida.
Flowers orange, thickly spotted with reddish brown; stems usually reddish.

2. I. biflora.
1. Impatiens pallida Nutt. PALE TOUCH-ME-NOT.

Low shaded ground along the upper Potomac; occasional. June-Sept. Eastern
N. Amer.

2. Impatiens biflora Walt. SPOTTED TOUCH-ME-NOT.
Low shaded ground; common. June-Sept. Eastern N. Amer. (J. fulva Nutt.)
Plants with pale yellow or pinkish flowers occur occasionally.

99. RHAMNACEAE. Buckthorn Family.
1. CEANOTHUS L.

Leaves 1-2 cm. wide, narrowed at the base, elliptic, glabrous; peduncles few, scarcely

if at all longer than the inflorescence. .... cece cece cece eee eeeee .-1. C. ovatus.
Leaves 2-6 cm. wide, usually rounded at the base, ovate, hairy beneath; peduncles
numerous, usually much longer than the inflorescence........ 2. C. americanus.

1. Ceanothus ovatus Desf.
Flats about Little Falls. May. Eastern U. 8.
Plants from our region were described by Rafinesque as C. herbaceus.!
2. Ceanothus americanus L. NEw JERSEY TEA.
Open woods. June. Eastern U.S.
The leaves were used as a substitute for tea during the Revolutionary War, hence
the common name.

100. VITACEAE. Grape Family.

Leaves digitately compound..........-.....2.-eee eee eees 1. PARTHENOCISSUS.
Leaves simple or pinnately compound.
Flowers in small short cymes or panicles; petals spreading at their tips; berry not

roX6 D0 0) (<a 2. AMPELOPSIS.
Flowers in elongate racemes, cymes, or panicles; petals falling away united by
their apices; berry edible ...........-.-.-.-2 22-22 -e eee eee eee eee eee 3. VITIS.

1. PARTHENOCISSUS Planch.
1. Parthenocissus quinquefolia (L.) Planch. VIRGINIA CREEPER,

Ravines and deciduous forests. May-June; fr. Aug.Sept. Eastern N. Amer.
to Mex. (Ampelopsis quinquefolia Michx.; Psedera quinquefolia Greene.)

Parthenocissus tricuspidata Planch., the Boston ivy, is cultivated, covering walls
as does the Virginia creeper.

1 Med. Repos. N. Y. 11: 360. 1808.

202 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

2. AMPELOPSIS Michx.

Leaves 2--3-pinnate, the leaflets ovate, toothed, 1 cm. lohg or more; fruit black.
1. A. arborea.
Leaves of two forms (dimorphic), the larger entire and 3-lobed, the smaller 2-5 cm.
long, deeply 3-5-lobed; fruit bright blue or whitish........ 2. A. heterophylla.

1. Ampelopsis arborea (L.) Rusby. PEPPER VINE.
Moist woods; Terra Cotta. July; fr. Sept. Southeastern U. §., W. Ind., and Mex.
2. Ampelopsis heterophylla (Thunb.) Sieb. & Zucc.
Escaped in places. Native of eastern Asia; common in cultivation.

3. VITIS L. Grape.

Leaves floccose-woolly or tomentose beneath.

Pubescence brown-tomentose, persistent; tendrils commonly opposite each leaf;
leaves shallowly or not at all lobed, the margin dentate, the teeth short; fruit
purple or amber-colored, about 15 mm, in diameter.........-.. 1. V. labrusca.

Pubescence brownish, at length white, persistent only on the veins beneath; ten-
drils not opposite all the leaves; leaves not lobed, or deeply 3 or 5-lobed, the
margin more or less coarsely dentate; fruit black, about 10 mm. in diameter.

2. V. aestivalis.
Leaves glabrous or nearly so.

Leaves more or less incisely toothed or lobed, the lobes acuminate; fruit 10 mm.
in diameter or more, bluish black, sweet. Flowers and fruit in loose clusters.

3. V. vulpina.
Leaves coarsely toothed (sometimes lobed), the teeth short; fruit about 6 mm. in
diameter.
Leaves commonly longer than broad (measured from sinus to apex), 7 cm. wide
orymore; fruit in loose clusters, black, sour..........--.-- 4. V. cordifolia.
Leaves broader than long, smaller; fruit in compact clusters, black, with a bloom,
sweet.......-....... eeeeeeee weeeeeeee ee eeeee wee eee eeee 5. V. rupestris.
1.4 Vitis labrusca L. Fox GRAPE.
Thickets and low woods. May-June; fr. Aug. Eastern U.S.
2. Vitis”aestivalis Michx. SUMMER GRAPE.
Thickets and along fences. May-June; fr. Aug.-Sept. Eastern N. Amer.
8. Vitis vulpina L. FROST GRAPE.
Thickets. May-June; fr. July-Aug. Eastern N. Armer. (V. riparia Michx.)
4. Vitis cordifolia Michx. CHICKEN GRAPE.
Woods and along fences. May-June; fr. Oct. Eastern U.S.
5. Vitis rupestris Scheele. SAND GRAPE.

Ravines and along river banks. June; fr. Aug. Eastern U. S., from Pa. south-
ward.

101. TILIACEAE. Linden Family.

1. TILIA L.
1. Tilia americana L. Basswoop.
Rich woods, usually near water; frequent. May. Eastern N. Amer.
Several European species, usually known as lindens, are cultivated as shade trees
along our streets.

102. MALVACEAE. Mallow Family.

Althaca cannabina L., a native of Europe, was reported by Ward as growing in waste
ground in east Washington, but has not been seen in many years. It resembles the
common mallow, Malva rotundifolia, from which it is easily distinguished by its
yellow flowers with purple center, and 6—-9-bracted involucel.

FLORA OF THE DISTRICT OF COLUMBIA. 203

Stamen column anther-bearing below the summit; fruit a 5-celled capsule.
4. HIBISCUS.
Stamen column anther-bearing at the summit only; fruit composed of 5-many carpels
arranged in a circle and separating at maturity.

Carpels of the fruit dehiscent, 2-several-seeded; leaves entire, velvety-hairy.
8. ABUTILON.
Carpels indehiscent, 1-seeded; leaves serrate or dentate, glabrous or pubescent, but

not velvety.

Bractlets none at the base of the calyx; corolla yellow or white........ 2. SIDA.
Bractlets 3 at the base of the calyx; corolla white, blue, or purplish.
1. MALVA.
1. MALVA L.
Plants erect; petals 2-4 times as long as the calyx, purple...........1. M. sylvestris.

Plants prostrate; petals about twice as long as the calyx, lavender or bluish.
2. M. rotundifolia.

1. Malva sylvestris L. HiaH MALLOW.

Waste places and along roadsides; Georgetown and the upper Potomac. May-July.
Adventive from Eur.
2. Malva rotundifolia L. CHEESES.

Waste ground; frequent. May-Aug. Naturalized from Eur. and western Asia;
widely distributed as a weed in temperate regions.

Malva crispa L., curled mallow, has been collected at Tennallytown; adventive
from Eur. M. moschata L., musk mallow, also native of Eur., has been found as a waif
in waste ground.

2. SIDA L.
Leaves linear or lanceolate, not lobed; flowers yellow, solitary in the axils, or in short-
s‘alked axillary clusters of 2 or 3........22eeeeeee cece ce eceeeeecees 1. S. spinosa.

Leaves palmately lobed; flowers white, in long-stalked axillary clusters,
2. S. hermaphrodita.

1. Sida spinosa L. FALSE MALLOW.
Waste places and fields. July-Sept. Eastern U. S. to tropical Amer,
2. Sida hermaphrodita (L.) Rusby. VIRGINIA MALLOW.

Along the Potomac, in rocky places, Plummers Island to Long Bridge. July-
Sept. Eastern U.S. (S. napaea Cav.)

3. ABUTILON Mill.

1. Abutilon theophrasti Medic. VELVET-LEAF,
Waste places and fields; common. July-Aug. Naturalized from southern Asia.
(A. abutilon Rusby; A. avicennae Gaertn.)

4, HIBISCUS L.

Mibiscus esculentus L., okra, has been found as a waif in waste ground; also H.
trionum L., flower-of-an-hour, an annual with a bladdery-inflated calyx.

Plants shrubby..........2 2222.22. eee eee eee eee eee cece eee eeee 1. H. syriacus.
Plants herbaceous.
Leaves glabrous on both sides, lobed at base or halberd-shaped; flowers pink.

2. H. militaris.

Leaves white-pubescent beneath, lanceolate or ovate; flowers cream-colored, with
CriMSON CYC.......2.. 2.022 eee eee eee eee 3. H. palustris.

1. Hibiscus syriacus L. SHRUBBY ALTHAEA. ROSE OF SHARON.

An ornamental shrub, native of Asia, cultivated in gardens; often escaping to
vacant lots and waste ground. July—Sept.
Flowers white, rose, or lilac, with a deep rose-colored eye.

204 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

2. Hibiscus militaris Cav. Rose MALLOW .
Along the Potomac. July-Aug. Eastern U.S.
8. Hibiscus palustris L. SwAMP MALLOW.

Tidal marshes along the Potomac and Eastern Branch. July-Aug. Southeastern
U.S.

This species has been confused with the pink-flowered H. moscheutos L., found
north of our region.

Gossypium hirsutum L., upland cotton, is occasionally found in freight yards and
along railroad tracks. As cotton is easily killed by freezing temperatures, the plants
do not survive the winter.

108. HYPERICACEAE. St. John’s-wort Family.

Sepals 4, in unequal pairs; petals 4................-.- 2.2 eee e eee enone 1. ASCYRUM.
Sepals and petals 5.
Petals yellow, convolute in bud.
Leaves normal, not reduced to scales.............-....-+----- 2. HYPERICUM.
Leaves reduced to minute appressed scales. ..........--------- 3. SAROTHRA.
Petals pink or greenish purple, imbricate in bud........-.--.-- 4. TRIADENUM.

1. ASCYRUM L.

Plants erect, with few erect branches, 30-60 cm. high; leaves clasping, oval or broadly
oblong, thick; styles 3 or 4; pedicels without hiacts near the flower..1. A. stans.
Plants diffusely branched, 12-25 cm. high; leaves sessile, oblong or obovate, narrow,
thin; styles 2; pedicels 2-bracted near the flower............-- 2. A. hypericoides.

1, Ascyrum stans Michx. © Sr. PeTER’s-wort.
Dry sandy soil; frequent northeast of Washington. Aug. Eastern U.S.

Flowers showy, 1-2 cm. broad.

2. Ascyrum hypericoides L. St. ANDREW’S CROSS.
Sandy orrocky barrens; common. July-Sept. Eastern U.S. (A. crux-andreae L.)
Flowers not so conspicuous as in the preceding, usually about 1 cm. broad. The

plant derives its common name from the arrangement of sepals and petals in the form

of a St. Andrew’s cross.

2. HYPERICUM L. Sr. Joun’s-worr.
Plants tall shrubs.
Flowers 10-20 mm. broad; pods 10-15 mm. long .......-...------ 1. H. prolificum.
Flowers 8-12 mm. broad; pods 5-8 mm. long ..........---.----- 2. H. densiflorum.
Plants herbs, sometimes woody at the base.
Stamens numerous (15-40); flowers 7-25 mm. broad; plants perennial.
Leaves linear or oblong, not conspicuously black-dotted, 8-23 mm. long, 1-8 mm.

8 Ce (<r 8. H. perforatum.

Leaves broadly oblong, oval, or ovate-lanceolate, conspicuously black-dotted.

25-75 mm. long, 8-16 mm. wide.................-2+---- 4. H. denticulatum.
Stamens few (5-12); flowers 1-7 mm. broad; plants usually annual.

Leaves ovate, oval, or oblong, 5-7-nerved ..........-.---------- 5. H. mutilum.

Leaves linear, 3-nerved..........---0..0--- ee eee eee eee eee eee 6. H. canadense.

1. Hypericum prolificum L. SHRUBBY St. JOHN’S-WORT.

Sandy or rocky soil; common. July. Eastern U.S.
Internodes of the younger branches mote or less exposed.
2. Hypericum densiflorum Pursh.
Pine barrens; rare; reported from Surrattsville and Berwyn. Eastern U. 8.
Much branched above, the branches leafy, the internodes hardly visible.

FLORA OF THE DISTRICT OF COLUMBIA. 205

8. Hypericum perforatum L. Common St. JoHN’s-wort.
Fields and waste places; frequent. July. Eastern U. S.; naturalized from Eur.
4. Hypericum denticulatum Walt.
Damp places; common. July. Eastern U. 8S. (H. punctatum Lam.; H. corym-
bosum Muhl.)
Usually taller than H. perforatum and not so much branched.

5. Hypericum mutilum L.

Low grounds; frequent. Aug.—Oct. Eastern N. Amer.

A small-flowered small-capsuled species (capsules 1-2 mm. long), with 4-angled
branchlets. A specimen of this species was reported by Steele as H. majus (A. Gray)
Britton.

6. Hypericum canadense L.
Wet or dry soil; frequent. Aug.—Oct. Eastern N. Amer.

8. SAROTHRA L.
1. Sarothra gentianoides L.

Sandy or rocky soil; frequent. Aug.—Sept. Eastern U. 8. (Hypericum sarothra
Michx.; H. gentianoides B.S. P.)

4. TRIADENUM Raf.

1. Triadenum virginicum (L.) Raf. Marsa St. JoHN’s-wortT.
Marshes or swamps; frequent north and east of Washington. July-Aug. Eastern
N. Amer. (Elodea virginica Nutt.; Hypericum virginicum L.)
Distinguished from our other members of the family by the distinct reddish tinge,
and by the large leaves, which are frequently 4 cm. long.

104. ELATINACEAE, Waterwort Family.

1. ELATINE L. WatTerwort.

1. Elatine americana (Pursh) Arn.

Reported by Holm from near Chain Bridge, on the Virginia shore of the Potomac.
Widely distributed in N. Amer.

It may be found near or submerged in water; characterized by membranaceous
stipules between opposite leaves, and minute axillary flowers.

105. CISTACEAE. Rock-rose Family.

Petals 5, yellow, crumpled in bud, fugacious or sometimes wanting; style short;

ovules numerous in the petal-bearing flowers............ 1. HELIANTHEMUM.
Petals 3, not yellow, flat in bud, persistent; style none; pod partly 3-celled, the
imperfect partitions bearing broad 2-seeded placentae..........---- 2. LECHEA.

1. HELIANTHEMUM Mill.

1. Helianthemum canadense (L.) Michx. FROSTWEED.
Dry soil; frequent northeast of Washington. May. Eastern U.S. (Crocanthemum
canadense Britton.)
An erect hoary-pubescent perennial herb, with oblong-linear leaves, the flowers of
two kinds, the early ones large and solitary, the later ones small and clustered.

2. LECHEA L. PINWEED.

Leaves of the basal shoots elliptic or oblong, not more than three times as long as
broad.
Outer sepals exceeding the inner ones; panicle very leafy......--..-.- 1. L. minor.
Outer sepals shorter than the inner; panicle usually not very leafy.
2. L. racemulosa.

206 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Leaves of the basal shoots narrowly lanceolate to linear, usually more than 3 times as
long as broad.

Stem leaves narrowly linear; inner sepals l-nerved................. 8. L. tenuifolia,

Stem leaves oblong-linear; inner sepals 3-nerved..................- 4. L. leggettii.

1. Lechea minor L.
Dry soil; between Chevy Chase and Glen Echo. May. Eastern U.S.
Erect, 30-60 cm. high, with mostly oval or oblong leaves.
2. Lechea racemulosa Lam.
Dry or rocky soil; common. Eastern U.S.
Erect, 30-50 cm. high, with linear-oblong stem leaves.
8. Lechea tenuifolia Michx.
Dry sterile soil; infrequent; Addison Heights, Hyattsville. Eastern U.S.
A low diffuse plant, usually not more than 20 cm. high, with very narrow stem
leaves, these about 1 mm. wide and 1-1.5 cm. long.
4. Lechea leggettii Britt. & Holl.
Dry soil; frequent. Eastern U.S.
Plants 30-50 cm. high, the stem leaves 3-4 mm, wide and 1.5 cm. long.

106. VIOLACEAE. Violet Family.

Sepals not prolonged and auricled at the base; petals greenish; plants usually 60-
80 cm. high, the stout stems bearing numerous elliptic or oval, entire leaves.

1. CUBELIUM.

Sepals prolonged and auricled at the base; petals violet, white, or yellow; plants

usually less than 40 cm. high, the stems slender or none....... ceeeeee 2. VIOLA.
1. CUBELIUM Raf.
1. Cubelium concolor (Forst.) Raf. GREEN VIOLET.

Low rich woods along the Potomac; rare. Apr.—May. Eastern U.S. (Jonidium
concolor Benth. & Hook.; Hybanthus concolor Spreng.; Solea concolor Ging.)

2. VIOLA L.) VIOLET.

Plants with slender, elongate, often branched, leafy stems at flowering time.
Stipules entire or nearly so, the lower ones scarious; petals yellow; capsules usually

densely woolly...........-.-2-2.-.-.2---2----------0-5- seeeeee 1. V. eriocarpa.
Stipules deeply toothed or lobed, green; petals violet or white; ripe capsules
straw-colored.
Plants perennial, with rootstocks; stipules small, deeply toothed.
Petals pale violet; leaves rounded at the apex ............-..-- 2. V. conspersa.
Petals white or creamy white; upper leaves very acute............ 8. V. striata.
Plants annual, with fibrous roots; stipules large and leaflike, coarsely lobed, the
lobes not gland-tipped........-...........2-2.----2---20--- 4. V. rafinesquii.

Plants stemless, the leaves and flower stalks rising directly from a rootstock, the plants
sometimes developing long slender runners.
Plants developing long slender runners after flowering; rootstocks long and very
slender; petals white, the lower lined with purple.
Leaves never heart-shaped, tapering or truncate at the base.
Leaves lanceolate, usually less than 2 cm. wide, several times as long as broad.

long-tapering at the base.............222-2-2--.0202-200+- 5. V. lanceolata,
Leaves ovate, usually more than 2 cm., often 5 cm. wide, not more than twice
as long as broad, usually truncate at the base........... 6. V. primulifolia.

1The author of the account of this genus is indebted to Dr. Ezra Brainerd for
generous assistance in the determination of the local violets, especially those of
supposed hybrid origin.

FLORA OF THE DISTRICT OF COLUMBIA. 207

Leaves heart-shaped, deeply lobed at the base.
Leaves glabrous. ............2. 0.0 c cece cece ceccccecuccccecece 7. V. pallens.
Leaves finely hairy on the upper surface....................2--. 8. V. blanda.
Plants without runners, the rootstocks stout and fleshy; petals violet or purplish

(rarely abnormally white).

Plants without cleistogamous flowers; none of the petals bearded. Leaves
divided into numerous narrow lobes.....-......--2.cececeeeee 9. V. pedata.
Plants with cleistogamous flowers; lateral petals bearded.

Leaves neither heart-shaped nor kidney-shaped, triangular, oblong, ovate, or
deeply lobed, or sometimes almost heart-shaped with large coarse teeth
near the base.

Leaves all deeply divided into numerous narrow lobes. ...10. V. brittoniana.
Leaves not divided, sometimes with a few small lobes near the base.
Leaves broadly triangular when mature, glabrous or nearly so.

11. V. emarginata.
Leaves lanceolate to ovate-oblong.

Leaves glabrous or nearly so, long-petioled, mostly lanceolate or trian-
gular-lanceolate 1.2.2.2... 2.2.2. 2ccceeececececes 12. V. sagittata.
Leaves copiously hairy, short-petioled, ovate-oblong..18. V. fimbriatula.
Leaves, at least some of them, heart-shaped or kidney-shaped, finely and
evenly toothed, some of the leaves, also, often lobed.
Leaves in part deeply lobed.
Leaves, except the earliest ones, divided almost or quite to the midrib

into numerous narrow lobes, glabrous or nearly so...... 14, V. stoneana.
Leaves mostly with short lobes, the lobes few (usually 3 or 5) and broad,
usually very hairy..........2.-2-......0.2022000-. -----15. V. triloba.

Leaves not lobed.
Leaves finely hairy on one or both surfaces.
Leaves loosely hairy beneath, usually erect; seeds dark brown.

16. V. sororia.

Leaves glabrous beneath, with fine appressed hairs on the upper surface,
often lying flat on the ground; seeds buff.......... 17. V. hirsutula.
Leaves glabrous or practically so, the hairs, if present, mostly confined to

the veins.
Beard of the lateral petals of strongly knobbed hairs; cleistogamous
flowers long and slender, on erect peduncles, their capsules green,
18. V. cucullata.
Beard of the lateral petals not knobbed; cleistogamous flowers short,
ovoid, their capsules usually purplish.
Cleistogamous flowers on ascending peduncles; capsules 5-8 mm.
long; seeds buff; leaves mostly longer than broad. .19. V. affinis.
Cleistogamous flowers on short prostrate peduncles; capsules 10-15
mm. long; seeds dark brown; full-grown leaves mostly as broad
as long, often broader............-.........-. 20. V. papilionacea.

Viola pectinata Bicknell was reported from Riverdale by House. No specimens
have been seen by the writer.

1. Viola eriocarpa Schwein. YELLOW VIOLET.
Moist woods, often in alluvial soil, frequent and sometimes abundant. Apr.-

May. Northern states, south to Ga. (V. pubescens, V. pubescens ertocarpa, and V.
glabella of Ward’s Flora; V. scabriuscula Schwein.)

The capsules are usually densely woolly, but sometimes glabrous.

208 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

2. Viola conspersa Reichenb. Doa VIOLET
Low ground or shaded hillsides; Rock Creek Park, and between Cabin John and
Rockville; rare. Apr.-May. Eastern N. Amer.
The species has been reported from our region under the incorrect names of V.
labradorica and V. canina sylvestris.
3. Viola striata Ait. CREAM VIOLET.
Low woods, usually in alluvial soil, along the Potomac; sometimes cultivated and
escaping. Apr.-May. Northern states, south to Ga.
A tuft of flowering plants is shown in plate 25B.
4. Viola rafinesquii Greene. FIELD PANSY.
Fields and open woods; common. Apr.-May. Eastern U.S. (V. tenella Muhl.;
V. tricolor arvensis of Ward’s Flora.)
Viola tricolor L., the pansy, sometimes escapes to waste ground.
5. Viola lanceolata L. LANCE-LEAF VIOLET.
In bogs; frequent about Hyattsville, and in a few localities elsewhere. Apr.-May.
Eastern U. 8.
6. Viola primulifolia L. PRIMROSE VIOLET.
Low wet ground, chiefly on the Coastal Plain; common. Apr-May. Eastern
N. Amer.
%. Viola pallens (Banks) Brainerd.
In bog below Great Falls, Va. Northern states, south to S. C.
8. Viola blanda Willd. WHITE VIOLET.
On rocks along the Patuxent at Laurel; Paint Branch. Apr.May.. Eastern
N. Amer.
Viola odorata L., the English violet, was reported from Accotink by Holm. Native
of Eur.; often cultivated and sometimes escaping.

9. Viola pedata L. PANSY VIOLET,
Dry open slopes or in thin woods; common, Apr.-May. Eastern U.S. (V. pedata
bicolor Pursh.)

Known also as bird-foot violet. In the typical form of the species the two upper
petals are dark violet, the lower ones pale lilac-purple. In another form all the petals
are lilac-purple.

10. Viola brittoniana Pollard. BRITTON VIOLET.

Moist sandy soil; vicinity of Hyattsville, Bladensburg, and Riverdale. Apr.—May.
Me. to Va.

This is one of our handsomest violets; the large flowers are borne on remarkably
long peduncles.

VIOLA BRITTONIANA X CUCULLATA House.

About Riverdale and Hyattsville. (V. notabilis House.) This is a plant of very
distinctive appearance. The leaves are broadly ovate-triangular, coarsely and
irregularly but shallowly toothed or lobed. The cleistogamous flowers are borne on
very slender peduncles longer than the leaves.

VIOLA BRITTONIANA X EMARGINATA House.

Hyattsville, according to House. The leaves in outline resemble those of V.
brittoniana, but they are much less deeply lobed.
VIOLA BRITTONIANA X saaitrata House.

Near Riverdale. The leaf outline strongly suggests V. sagittata, but the leaves are
deeply laciniate-lobed near the base.
11. Viola emarginata (Nutt.) Le Conte.

Dry woods and hillsides, chiefly on the Coastal Plain; common. Apr.—May.
N. Y. to Ga.

FLORA OF THE DISTRICT OF COLUMBIA. 209

The typical form of the species has broadly triangular leaves, with coarse teeth or
lobes at the base; the earliest leaves are usually finely and almost evenly toothed,
and they are narrower than the later ones.

VioLA EMARGINATA X FIMBRIATULA Brainerd.
Frequent with V. emarginata. The leaves resemble those of either parent, but
they are more pubescent than in V. emarginata and less so than in V. fimbriatula.

VIOLA EMARGINATA X HIRSUTULA Brainerd.
Takoma Park. Leaves in shape like those of V. emarginata, but with the peculiar
pubescence of V. hirsutula. (V. emarginata villosa House.)

VIOLA EMARGINATA X PAPILIONACEA House.
Takoma Park (the type locality) and Glen Carlyn. The leaves resemble those of
V. papilionacea, but they are more deeply toothed near the base.

VIOLA EMARGINATA X SAGITTATA Brainerd.

Frequent with the parent species. Both V. emarginata and V. sagittata are glabrous
and the hybrid differs only in having the leaves intermediate in form between the two.
lla. Viola emarginata acutiloba Brainerd.

Brookland, Takoma Park, and Hyattsville. Distinguished from the species by
having the mature leaves 5-cleft or 5-parted, the middle lobe lance-oblong, the lateral
and basal lobes also long, but shorter than the terminal one. It is known from Staten
Isl., N. Y., and from our region.

VIOLA EMARGINATA ACUTILOBA X FIMBRIATULA Brainerd.
Brookland. In outline the leaves resemble those of V. emarginata acutiloba, but
they are more or less pubescent.

VIOLA EMARGINATA ACUTILOBA X PAPILIONACEA Brainerd.
Brookland. Leaves in outline almost like those of V. papilionacea, but the
margins deeply lobed in the lower half or two-thirds.

VIOLA EMARGINATA ACUTILOBA X SAGITTATA Brainerd.
Takoma Park and Hyattsville. Leaves in outline much like those of V. sagittata,
put slightly broader and with few deep narrow lobes at the base.

12. Viola sagittata Ait. ARROW-LEAF VIOLET.

Moist woods or meadows; common. Apr.-May. Northern states, south to Ga.

The leaves and stems are usually glabrous, but sometimes finely pubescent.

13. Viola fimbriatula J. E. Smith.

Dry fields and hillsides, chiefly on the Coastal Plain; common. Apr.-May. East-
ern N. Amer. (V. ovata Nutt.; V. sagittata hicksit Pollard; V. sagittata of Ward's
Flora, in part.)

VIOLA FIMBRIATULA X PAPILIONACEA Brainerd.

Along the Potomac and Eastern Branch. Leaves similar to those of V. papilionacea
but narrower, sometimes slightly lobed at the base, and more or less pubescent.
VIOLA FIMBRIATULA X SAGITTATA Brainerd.

Rather widely distributed in our region. Leaves in outline intermediate between
those of the two species and very variable, usually copiously pubescent. (V. sagittata
of Ward’s Flora, in part.)

Another hybrid, V. fimbriatula X villosa (=hirsutula Brainerd) was reported by

House from Takoma Park. No material has been seen by the writer.
14, Viola stoneana House.

Usually in thin moist woods; frequent. May. N. J. to Md. (V. septemloba of
many authors, not of Le Conte; V. cucullata palmata of Ward’s Flora, in part.)
VIOLA STONEANA X TRILOBA Brainerd.

Widely distributed in our region. Leaves cut as in V. stoneana, but more or less
pubescent as in V. triloba.

69289—19——_14

210 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

15. Viola triloba Schwein.
Dry or moist woods; frequent. Apr-May. New Eng. toGa. (V. palmata of some
authors, not of Linnaeus; V. vespertilionts Greene; V. ornithodes Greene.)

V. ornithodes was described from plants growing in Rock Creek Park; V. vespertil-
tonis from specimens from Brookland.

16. Viola sororia Willd. Downy VIOLET.

Moist meadows or banks or in rather dry woods; frequent along the Potomac, infre-
quent elsewhere. Apr.—May. Northern states, south to N. C. (V. laetecaerulea
Greene.)

17. Viola hirsutula Brainerd.

Dry fields or hillsides, commonly in pine woods; frequent. Apr._May. N. Y to
Ga. (V. villosa of many authors, not of Walter; V. cucullata cordata of Ward’s Flora.)
VIOLA HIRSUTULA X sororta Dowell.

Naucks and Hyattsville. Leaves in outline similar to those of V. sororia, larger
than those of V. hirsutula, with the characteristic pubescence of the latter.

VIOLA HIRSUTULA X STONEANA Brainerd.

Hyattsville. Leaves lobed much as in V. stoneana, but less deeply, with the pubes-

cence of V. hirsutula. (V. stoneana X villosa House.)

VIOLA HIRSUTULA X TRILOBA Brainerd.
Glen Sligo. Leaves with the pubescence of V. hirsutula; lobed as in V. triloba, or
some of them only coarsely toothed.

18. Viola cucullata Ait,

Along streams and in bogs; frequent, Apr.-May. Eastern N. Amer. (V. macrotis
Greene; V. fontana Greene.)

The type of V. macrotis is from Surrattsville; that of V. fontana was collected along
Rock Creek just outside the District.

VIOLA CUCULLATA X PAPILIONACEA Brainerd.

Collected at several stations. In general characters almost intermediate between
the parents.

A plant from Hyattsville was reported by House as V. cucullata x emarginata Brain-
erd. The writer has not seen the specimens. The Long Island plant (V. lavandu-
lacea Bicknell) to which this interpretation was given is now believed to be V. cucul-
lata X primulifolia. The Hyattsville plant is considered a true hybrid between
V. cucullata and V. emarginata.

19. Viola affinis Le Conte. SLENDER VIOLET.
Moist meadows and woods; common. Apr.-May. Eastern U. S. (V. nepetaefolia
Greene.)
The type of V. nepetaefolia was collected beyond Anacostia.

VIOLA AFFINIS X CUCULLATA Brainerd.

At several stations north of Washington. Differing from V. afinis in the larger
leaves, long slender cleistogamous flowers, and long-auricled sepals; from V. cucullata
in the very acute leaves and brown-dotted capsules,

VIOLA AFFINIS X HIRSUTULA Brainerd.

Several scattered stations. Leaves in outline like those of V. afinis, with the
pubescence of V. hirsutula. (V. affinis X villosa Brainerd.)
VIOLA AFFINIS X PAPILIONACEA House.

Widely distributed in our region; the type from Woodridge. Leaves larger than
those of V. affinis, but usually resembling them in shape and texture; flower and fruit
characters intermediate between those of the parents. (V. filicetorum Greene.)

V. filicetorum was based upon material from our region.

VIOLA AFFINIS X SAGITTATA Brainerd.

Patuxent. Leaves intermediate between those of the two parents; capsules minutely

pubescent asin V. affnis.

FLORA OF THE DISTRICT OF COLUMBIA. 211

20. Viola papilionacea Pursh. BUTTERFLY VIOLET. _
In all kinds of situations; very abundant; our commonest violet. Apr.—May. East-
ern U.S. (V. domestica Bicknell; V. familiaris Greene; V. cucullata of Ward’s Flora;
V. communis Pollard.)
The types of V. familiaris and V. communis are from our region.
VIOLA PAPILIONACEA X HIRSUTULA Brainerd.

» Collected at several scattered stations. Leaves in outline intermediate between
those of the parents, with the pubescence of V. hirsutula. (V. papilionacea X villosa
Pollard, the type from Darlecarlia Reservoir.)

VIOLA PAPILIONACEA X SAGITTATA Brainerd.

Darlecarlia Reservoir and Takoma Park. Leaves regularly toothed, narrower
than in V. papilionacea. (V. conjugens Greene.)
VIOLA PAPILIONACEA X sororia Brainerd.

Collected at several scattered stations. Leaves like those of the parents, but only
very slightly pubescent. (V. grandis Greene; V. induta Greene.)

The type localities of V. grandis and V. induta are within our region.
VIOLA PAPILIONACEA X TRILOBA Brainerd.

Common with the parents. Leaves less deeply lobed than in V. triloba, more or
less pubescent.

107. PASSIFLORACEAE. Passion-flower Family.
1. PASSIFLORA L. PAssIon-FLOWER.

Passiflora incarnata L., maypops or maracocks, is cultivated within our limits,
usually trained over trellises and pergolas. Native from central Va. southward.

1. Passiflora lutea L.
Common in thickets, especially along the Potomac. May-Aug. Southeastern U.S.

108. CACTACEAE. Cactus Family.

1. OPUNTIA Mill.
1. Opuntia vulgaris Mill. PRICKLY PEAR.
Rocky or ‘sandy soil; Plummers Island and Great Falls. June. Eastern U.S.
(O. opuntia Karst.)
A tuft of plants in fruit is shown in plate 34B.

109. DAPHNACEAE. Leatherwood Family.

1. DIRCA L.
1. Dirca palustris L. LEATHERWOOD. MoosEWOoD.
Low places along the Potomac. Apr. Eastern U.S.

110. LYTHRACEAE, Loosestrife Family.

Calyx tube short, campanulate or hemispheric. Flowers regular.
Leaves opposite; flowers small, solitary or few; petals 4; low annual herbs.

1. ROTALA.
Leaves mostly whorled; flowers large, densely clustered; petals 5 (rarely 4); large
aquatic perennial herbs.............. eee eee cece eee ee eee eens 2. DECODON.

Calyx tube cylindric or tubular.
Flowers regular; calyx tube symmetric; plants perennial, not viscid-hairy.
3. LYTHRUM.
Flowers irregular; calyx tube spurred or enlarged on one side at base; plants annual,
Viscid-hairy.............. 0c ccc e eee een enn eneeees 4, PARSONSIA.

912 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

1. ROTALA L.
1. Rotala ramosior (L.) Koehne. TOOTH-CUP.
Low or wet ground; frequent. Aug.-Sept. Eastern U. 8. (Ammannia humilis

Michx.)
2. DECODON J. F. Gmel.

1. Decodon verticillatus (L.) Ell. SwAMP LOOSESTRIFE.
Swampy ground; rare. Aug. Eastern U.S. (Nesaea verticillata H. B. K.)
The stems are 1-2 meters high, and root from the tip when they reach the mud.

3. LYTHRUM L. Loosestrire.

Flowers solitary, axillary, small; stamens not more numerous than the petals; leaves

alternate; stems glabrouS.............-. 2. ee cece eee ene eee eeee 1. L. alatum.
Flowers in dense spikes, large; stamens twice as many as the petals; leaves opposite
or whorled; stems pubescent.............-.ceeeee eee eeeeeeees 2. L. salicaria.

1. Lythrum alatum Pursh.
Low grounds; frequent along the Potomac. June-Aug. Eastern N. Amer.
A tall wandlike perennial; stem angled and often slightly winged.
2. Lythrum salicaria L. PURPLE LOOSESTRIFE.
Wet meadows and swamps. June-July. Hunting Creek and perhaps elsewhere.
Northeastern states; naturalized from Eur.
4, PARSONSIA P. Br.

1. Parsonsia petiolata (L.) Rusby.
Dry soil; frequent. Aug.Oct. Eastern U. 8. (Cuphea viscosissima Jacq.; C.
petiolata Koehne.)

111. MELASTOMATACEAE. Meadow beauty Family.

1. RHEXIA L. MEADOW BEAUTY.

Stems not angled; leaves oblong or elliptic, mostly petioled...........1. BR. mariana.
Stems square or angled; leaves oval or ovate, mostly sessile........... 2. R. virginica.

1. Rhexia mariana L.
Swamps northeast of Washington, infrequent. Aug. Eastern U.S. *

2. Rhexia virginica L.
Swamps; frequent. July-Sept. Eastern U.S.

112. ONAGRACEAE. Evening primrose Family.

Petals and calyx lobes 2 each; fruit burlike. Leaves thin, opposite; flowers white.
1. CIRCAEA.
Petals and calyx lobes 4 each or more; fruit not burlike.
Fruit indehiscent, nutlike. Leaves alternate; flowers white or pink, in wandlike
Bpikes..... 2.2... 2. eee eee ee ee eee eect e ec eeeeeeees 2. GAURA.
Fruit a many-seeded capsule, opening by valves or by a pore.
Calyx tube not prolonged beyond the ovary.
Seeds with a tuft of silky hairs; calyx deciduous. Leaves alternate; flowers
Magenta ....-. 2... eee ee ee eee leneeas 8. CHAMAENERION.
Seeds naked; calyx persistent.
Stamens 8-12, in 2 rows. Leaves alternate; flowers yellow...4. JUSSIAEA.
Stamens 4, in 1 row.
Leaves opposite; stem creeping or floating; petals none, or small and pink.
5. ISNARDIA.
Leaves alternate; stems erect or ascending; petals conspicuous, yellow.
6. LUDWIGIA.

FLORA OF THE DISTRICT OF COLUMBIA. 213

Calyx tube prolonged beyond the ovary.
Seeds furnished with a tuft of silky hairs; flowers pink; leaves opposite, or
alternate above...--------- essere cere errs 7. EPILOBIUM.
Seeds naked; flowers yellow; leaves alternate.

Stamens equal in length; fruit long, cylindric.
Plants large (30-150 cm. high), rather stout; leaves minutely toothed; seeds
horizontal, angled........-------+2+----+eeetccrtte 8. OENOTHERA.
Plants small (10-70 cm. high), slender; leaves lobed; seeds ascending, not
angled........-e-e-eereeecceeeerreeessrtrrsys 9. RAIMANNIA.
Stamens unequal in length, the alternate longer; fruit short, obovoid. Leaves
linear to oblong, entire or with very small teeth.......-- 10. KNEIFFIA.

1. CIRCAEA L. ENCHANTER’S NIGHTSHADE.

1. Circaea latifolia Hill.
Woods; common. June-Aug. Eastern U.S. (C. lutetiana of American authors.)

2. GAURA L.
1. Gaura biennis L.
Dry soil; frequent. Aug.—Oct. Eastern N. Amer.

3. CHAMAENERION Adans.

1. Chamaenerion angustifolium (L.) Scop. PURPLE FIREWEED.
Clearings and newly burned lands; infrequent. Aug. Widely distributed in N.
Amer.; also in Eur. and Asia. (Epilobium angustifolium L.)

4. JUSSIAEA L.

1. Jussiaea decurrens (Walt.) DC.
Wet places along Hunting Creek. Aug.Sept. Southeastern U. §., north to Md.

. 5. ISNARDIA L.
1. Isnardia palustris L. . WATER PURSLANE.
Ditches and swamps along the Potomac and its larger tributaries; frequent. July-
Aug. Widely distributed in N. Amer. and in the Old World. (Ludwigia palustris
Ell.)
A succulent plant with ovate leaves tapering to a slender petiole. It forms a
characteristic reddish mat in our small streams and swamps.

6. LUDWIGIA L.

Plants hirsute; capsules bristly-pubescent; leaves oblong, or the upper lanceolate,

blunt at both ends, sessile......-.--------eeerererseecrcsetttt 1. L. hirtella.
Plants glabrous; capsules glabrous; leaves lanceolate or linear-lanceolate, acute or
pointed at both ends, short-petioled.......-.--++-e-eeerrceree 2. L. alternifolia.

1. Ludwigia hirtella Raf.
Holmead Swamp; not collected recently. July-Aug. N.J. to Tex.

2, Ludwigia alternifolia L. SEED-BOX.
Low woods and swamps;common. June-Aug. Eastern U. 8.
7, EPILOBIUM L. WILLOW-HERB.

1, Epilobium coloratum Muhl.
Low ground; frequent. Aug. Eastern U.S.

214 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

8. OENOTHERA L. Evenine PRIMROSE.

1, Oenothera biennis L.

Open places; common. J uly-Sept. Eastern N. Amer.

An extremely variable species, in recent years the subject of extensive investiga-
tions in plant breeding. The species is considered to consist of numerous “elementary
species,” three of which have been described by Bartlett! from our region: O. steno-
meres, O. brevicapsula, and O. ruderalis. O. stenomeres is a form with linear petals.

9. RAIMANNIA Rose.

1, Raimannia laciniata (Hill) Rose.
Dry open places, northeastward; infrequent. May-July. Eastern U. S. (Oeno-
thera sinuata L.; O. laciniata Hill.)

10. KNEIFFIA Spach. Sunprops.

Flowers small (usually 1 cm. broad or less). Flowers mostly borne on the upper third
of the plant and separated from the main leafy portion by an elongate internode.

1. EK. pumila,
Flowers large (1.5-2.5 cm. broad or more),

Pedicels elongate, longer than the capsule................. 2. K. longipedicellata.
Pedicels shorter than the capsule,
Capsule markedly club-shaped, tapering from the summit to the base.
3. EK. linearis.
Capsule oblong or nearly so, tapering slightly at the base....... 4. K. fruticosa.

1, Kneiffia pumila (L.) Spach.

Woods and open places; infrequent. May-June. Eastern N. Amer. (Qenothera
pumila L.)
2. Kneiffia longipedicellata Small.

Moist soil, chiefly eastward; frequent. May-July. Eastern U. S. (Ocenothera
longipedicellata Robinson.) .
3. Kneiffia linearis (Michx.) Spach,

Dry fields; frequent. May-June. Eastern U. S. (Ocenothera fruticosa linearis 8.
Wats.; O. linearis Michx.)
4. Kneiffia fruticosa (L.) Raim.

Dry soil; common. May-June. Eastern U.S. (Ocnothera fruticosa L.)

Trapa natans L., of the family Trapaceae, native of Eur., was formerly established
in fish ponds in Potomac Park but is now extinct.

113. HALORAGIDACEAE. Water milfoil Family,

Leaves all dissected into hairlike lobes..................... 1. MYRIOPHYLLUM.
Leaves, at least the upper ones, simple, shallowly toothed, the lower ones usually

dissected - 2.0.2... eee eee ec cece ccc, 2. PROSERPINACA.

1, MYRIOPHYLLUM L. Warer MILFOIL,

1. Myriophyllum spicatum J.

Hunting Creek. Widely distributed in N. Amer., Eur., and Asia,

Myriophyllum proserpinacoides Gill., parrot’s-feather, a native of Chile, is cultivated
in aquaria. For several years this plant has been grown in two fountains on the north
side of the Treasury Building, where it makes a striking display and attracts much
attention.

* Cybele Columb. 1: 37-56. 1914.

FLORA OF THE DISTRICT OF COLUMBIA. 215

2. PROSERPINACA L.

1. Proserpinaca palustris L. MERMAID-WEED,
Shallow water; along the Potomac and near Bladensburg; infrequent. June-
July. Widely distributed in N. Amer.

114, ARALIACEAE. Ginseng Family.

Hedera helix L., English ivy, native of Eur. and common in cultivation, has occa-
sionally spread to roadsides or woods.

Leaves whorled or opposite; leaflets usually 3 or 5.......-...-----.----- 1. PANAX.
Leaves alternate; leaflets numerous. ...........-.------ eee eee ee eee eee 2, ARALIA,
1. PANAX L.

Leaflets all slender-stalked, broadly obovate or oval, taper-pointed; roots long and

11180 C6) <a 1. P. quinquefolium.
Leaflets, at least the lateral ones, sessile, mostly oblanceolate to oblong, obtuse or
acutish; roots globose............ 26. eee e cece cee eee cece eee eens 2. P. trifolium.
1, Panax quinquefolium L. GINSENG.

Rich woods; rare. July-Aug. Eastern N. Amer. (Aralia quinquefolia Decaisne &
Planch.)

The roots are much used in China for their supposed medicinal virtues, and the
plants are cultivated in the United States to obtain the roots for export.

2. Panax trifolium L. GROUNDNUT.
Moist woods and thickets; occasional. Apr.-May. Eastern N. Amer. (Aralia
trifolia Decaisne.)
2. ARALIA L.

Plants shrubby, armed with stout spines; leaflets thick, pale beneath....1. A. spinosa.
Plants herbaceous, unarmed; leaflets thin, green.
Umbels of flowers numerous, in racemes or panicles; stems branched .2. A. racemosa.
Umbels of flowers 2-7, arranged in an umbel; stems simple........ 3. A. nudicaulis.

1. Aralia spinosa L. ANGELICA TREE.
Moist woods; infrequent. Aug.—Sept. Eastern U. 8.
Stems simple or branched, usually 3-5 meters high. Sometimes known as Hercules’

club.

2. Aralia racemosa L. SPIKENARD.
Rich woods; infrequent. July-Aug. Eastern N. Amer.
The roots are used in medicine.

3. Aralia nudicaulis L. WILD SARSAPARILLA.
Moist woods; frequent. May. Eastern N. Amer., westward to the Rocky Mts.
The roots are used as a substitute for the official sarsaparilla.

115. APIACEAE. Parsley Family.

Besides the genera listed below, the following plants of European origin have been
collected in our region, most of them as mere waifs: Bupleurum rotundifolium L.
(Washington, 1889, Coville); Carum carut L., caraway (waste ground along the river
front, 1899, Steele, two plants found); Foeniculum vulgare Hill, fennel (reported by
Steele); Scandix pecten-veneris L. (waste ground, 1898, Steele); Seseli libanotis Koch
(Maryland Agricultural College, 1905, J. B. S. Norton, one plant found).

Stem and basal leaves simple, not lobed. Flowers white or yellowish.
Leaves linear or linear-oblong, at least some of them spine-toothed; flowers in
dense heads...---.22-2 22222 e eee eee ee eee ee cece eee e ee eee eens 1. ERYNGIUM.
Leaves rounded, not spine-toothed; flowers in umbels...... 15. HYDROCOTYLE.

216 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Stem leaves compound or lobed, the basal leaves simple or compound.
Fruit (even when very young) covered with straight or hooked bristles.
Flowers sessile or nearly so, yellowish or white; leaves digitately compound,
of 3-7 leaflets. Fruit covered with hooked bristles......... 2. SANICULA.
Flowers pediceled, white; leaves pinnately compound, nsually with numerous
divisions.
Bracts at the base of the umbel large, divided into linear lobes. Fruit covered
with barbed bristles; plants very hairy...............-.... 8. DAUCUS,
Bracts at the base of the umbel small and entire or none.
Plants annual; fruit obtuse at the base, covered with hooked bristles.
4. TORILIS.
Plants perennial; fruit very acute at the base, with straight bristles.

5. OSMORRHIZA.
Fruit not bristly, sometimes pubescent.

Leaflets entire. Perennial; flowers yellow.................. 13. TAENIDIA
Leaflets or leaves toothed or lobed.
Flowers yellow or purplish. Plants perennial.
Leaves pinnate, the leaflets sessile, several; fruit flattened; bractlets none
at the base of the pedicels..................-..-005. 8. PASTINACA.
Leaves simple or ternately compound, the leaflets usually stalked, often
only 3; fruit not flattened; bractlets present at the base of the pedicels.
Fruit winged; leaves all divided....................... 12. THASPIUM.
Fruit not winged; leaves sometimes simple.................. 14. ZIZIA.
Flowers white.
Leaves once pinnate, the leaflets linear or lanceolate, finely toothed, sessile.
Plants perennial.
Fruit winged; bracts at the base of the umbel 3 or fewer, filiform, some-

times wanting; pedicels 6-18 mm. long............... 11. OXYPOLIS.
Fruit not winged; bracts at the base of the umbel 6 or more, conspicuous;
pedicels 2-6 mm. long...--........22.0...ccceeeececeeeeeee 18. SIUM.

Leaves not once pinnate with narrow-toothed leaflets, 2 or 3 times pinnate or
else 1-3 times ternate, the leaflets usually coarsely toothed or lobed,
usually stalked.

Bractlets none at the base of the pedicels. Leaves 3-parted; plants peren-

nial, glabrous......2...2....02ceeee ce ccecececcececes 7. DERINGA.

Bractlets present at the base of the pedicels.
Plants annual, low and slender.

Bracts none at the base of the umbel; plants sparsely pubescent.

6. CHAEROPHYLLUM.

Bracts present at the base of the umbel, divided into linear lobes;

plants glabrous................0....0eeeeee eee 19. PTILIMNIUM.

Plants perennial, tall and stout, or in one species very low but with

tuberous roots.

Plants low and slender, usually less than 15 cm. high, flowering in
early spring; umbel with a leaf at the base; roots bulblike,

16. ERIGENIA.

Plants tall and coarse, flowering in summer or autumn; umbel never

with a leaf at the base; roots not bulblike.
Branches of the umbel pubescent; fruit winged.

Leaflets usually 3, very hairy, deeply lobed; fruit winged on the

MATPIN.. 2... eee eee eee eee cee ee eee eee 9. HERACLEUM.

Leaflets more than 3, nearly or quite glabrous, shallowly toothed;

fruit winged on the back.................-. 10. ANGELICA

FLORA OF THE DISTRICT OF COLUMBIA. 217

Branches of the umbel glabrous; fruit not winged.
Leaflets deeply lobed; bracts present at the base of the umbel;
calyx teeth none; ribs of the fruit slender, not corky.
17. CONIUM.
Leaflets evenly toothed; bracts none or soon deciduous; calyx
teeth present; ribs ‘of the fruit thick, corky..... 20. CICUTA.

1. ERYNGIUM L.

Leaves net-veined; bracts at the base of the head toothed........ 1. E. virginianum.
Leaves parallel-veined; bracts entire..........-----+2+-eee eee e eee 2. E. aquaticum.

1. Eryngium virginianum Lam.
Marshes along the lower Potomac and its tributaries; frequent. July-Oct. N. J.
io Tex.

2. Eryngium aquaticum L. BuTTON SNAKEROOT.
Dry sandy bank, Cabin John, Aug., 1904 (J. H. Painter). Eastern and central
U.S. (E. yuccaefouwm Michx.)
Eryngium planum L., a European species with broad cordate leaves, was collected
along Massachusetts Avenue in 1899 (Steele).

2. SANICULA L. Bur SNAKEROOT.

Styles shorter than the bristles of the fruit; staminate flowers not in separate heads;
flowers white... .. Pn 1. S. canadensis.
Styles longer than the bristles; staminate flowers partly in separate heads; flowers
greenish yellow or greenish white.
Calyx teeth lanceolate; fruit about 6 mm. long; flowers greenish white.
2, S. marylandica.
Calyx teeth ovate; fruit about 3 mm. long; flowers greenish yellow. .3. S. gregaria.

1. Sanicula canadensis L.
Damp woods; common. May-June. Widely distributed in N. Amer.
2. Sanicula marylandica L.
Damp woods, chiefly along Rock Creek and the upper Potomac; frequent. May-
June. Widely distributed in N. Amer.
8. Sanicula gregaria Bicknell.
Moist woods, chiefly westward. May. Eastern N. Amer.
3. DAUCUS L.
1. Daucus carota L. CARROT.
Dry fields and waste ground; abundant. May-Aug. Native of Eur. and Asia;
widely naturalized in N. Amer.
The flowers are white, but the central one of the umbel is usually dark purple;
sometimes all the flowers are pinkish.

4. TORILIS Adans.

1. Torilis anthriscus (L.) Gmel. HEDGE PARSLEY.
Waste ground about Washington; probably not established. June-July. Native
of Eur.; adventive in the eastern U.S. (Caucalis anthriscus Huds.)

5. OSMORRHIZA Raf.

Style and its base together 1 mm. long or shorter; plants very hairy...1. O. claytoni.
Style and base together 2-4 mm. long; plants nearly glabrous. ..... 2. O. longistylis.
1. Osmorrhiza claytoni (Michx.) Clarke.

Moist woods; common. May. Eastern N. Amer. (0. brevistylis DC.; Washingtonia
claytoni Britton.)

The roots of this and the following species are edible; the flavor resembles that of
anise.

218 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

2. Osmorrhiza longistylis (Torr.) DC. SWEET CICELY.
Moist woods; common. May. Widely distributed in N. Amer. (Washingtonia
longistylis Britton.)
6. CHAEROPHYLLUM L. CueErvm..

1. Chaerophyllum procumbens (L.) Crantz.

Moist woods or edges of marshes along the Potomac and Eastern Branch; frequent.
Apr.-May. Eastern N. Amer.

Chaerophyllum bulbosum L., a tall perennial species, native of Eur., was collected
in Washington in 1899 and 1902.

7. DERINGA Adans.

1. Deringa canadensis (L.) Kuntze. Honeworr.
Moist woods, chiefly along Rock Creek and the upper Potomac. June-July.
Eastern N. Amer. (Cryptotaenia canadensis DC.)

8. PASTINACA L.

1. Pastinaca sativa L. Parsnip.
Waste ground; infrequent. June-July. Naturalized from Eur.

9. HERACLEUM L.

1. Heracleum lanatum Michx. Cow PARSNIP,
Collected by Ward on High Island; probably extinct now. May-June. Widely
distributed in N. Amer.

10. ANGELICA L. ANGELICA.

1, Angelica villosa (Walt.) B.S. P.
Dry soil; frequent. July-Aug. Eastern U. 8. (Archangelica hirsuta Torr. &
Gray.)
11. OXYPOLIS Raf.
1. Oxypolis rigidior (L.) Raf. CowBANE.
Swamps, northeastward. Aug.-Sept. Eastern U.S. (Archemora rigida DC.)

12, THASPIUM Nutt. MEapow PARSNIP.

1. Thaspium barbinode (Michx.) Nutt.
Woods; frequent westward. May-June. Eastern U. 8.

18. TAENIDIA Drude.

1. Taenidia integerrima (L.) Drude. YELLOW PIMPERNEL.
Rocky woods along Rock Creek and the upper Potomac. May-June. Eastern N.
Amer. (Pimpinella integerrima A. Gray.)

14. ZIZIA Koch. MEADOW PARSNIP.

Basal leaves, simple, heart-shaped; stems finely pubescent.............1. Z. cordata.
Basal leaves compound, with several leaflets; stems glabrous............. 2. Z. aurea.

1, Zizia cordata (Walt.) DC.

Dry or moist woods; frequent. Apr-May. Eastern U. S., westward to Oreg.
(Thaspium trifoliatum of Ward’s Flora.)
2. Zizia aurea (L.) Koch.

Woods along the upper Potomac. Apr.-May. Eastern N. Amer. (Thaspium
aureum Nutt.)

FLORA OF THE DISTRICT OF COLUMBIA. 219

15. HYDROCOTYLE L. Marsu PENNYWoRT.

Leaves peltate (the petiole attached at the middle of the blade, not at the base).

1. H. americana.
Leaves not peltate.

Flowers pediceled.........0..... 02200 eecce cc ceeeccceceeeee 2. H. ranunculoides.
Flowers sessile............... wee eee e eee ee eeeeees 8. H. rotundifolia.
1. Hydrocotyle americana ,.
In pools and along streams; frequent. July-Aug. Eastern N. Amer.
2. Hydrocotyle ranunculoides L. f.
Edges of streams and pools; frequent. May-July. Widely distributed in N. and
S. Amer.; also in the Old World.
8. Hydrocotyle rotundifolia Roxb.
Well established in the Smithsonian grounds. Summer, Native of Asia.

16. ERIGENIA Nutt.

1, Erigenia bulbosa (Michx.) Nutt. HARBINGER OF SPRING.
Along the upper Potomac, chiefly on the islands; rare. Apr. Eastern U. 8.
17, CONIUM L.
1, Conium maculatum L. PoIsON HEMLOCK.

Collected several times about Washington; doubtfully established. June-July.
Native of Eur.; widely naturalized in N. Amer.
The roots are very poisonous.

18. SIUM L.

1. Sium laeve Walt. HEMLOCK WATER PARSNIP.
About pools, Great Falls and Eastern Branch; rare. Sept. Widely distributed in
N. Amer. (S. cicutaefolium Gmel.) .

19. PTILIMNIUM Raf.

1. Ptilimnium capillaceum (Michx.) Raf. Mock BISHOP-WEED.
Wet soil, Custis Spring (Ward); not collected recently. EasternU.8. ( Discopleura
capillacea DC.)

20. CICUTA L.
Leaflets lanceolate or lance-oblong; bulblets none....................1. C. maculata.
Leaflets linear; bulblets present in the axils of the leaves............ 2. C. bulbifera.
1, Cicuta maculata L. WATER HEMLOCK.

Swamps and low ground; common. June-Aug. Eastern N. Amer.

The roots are very poisonous.
2. Cicuta bulbifera L.

Reported by Ward from the “ Alexandria Canal, opposite the Arlington estate,’’ and
by Holm from Great Falls, Northern N. Amer., south to Va.

116. CORNACEAE. Dogwood Family.

Flowers of two kinds, pistillate and staminate, greenish, the parts in 5’s, the petals
minute or none; leaves alternate; trees...............0cece cece cece 1. NYSSA.
Flowers all perfect, the parts in 4’s, the petals white and showy, or the flowers in
heads surrounded by large white petal-like bracts; leaves opposite, except in one
shrubby species; trees or shrubs...................0.02020-020eee 2. CORNUS.

220 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

1. NYSSA L.
1. Nyssa sylvatica Marsh. BLack GUM.
Rich soil, usually along streams or swamps, but sometimes on hillsides or in dry
fields; abundant. May. Eastern U.S. (N. multiflora Wang.)
The plants sometimes flower when only shrubs. Leaves bright crimson in autumn;
fruit nearly black, juicy, with a single ridged stone. The leaves are usually entire,
put on young trees are sometimes toothed.

2, CORNUS L. Do«gwoopn.

Flowers in dense heads, surrounded by large white petal-like bracts; trees; fruit red.
. 1, C. florida.
Flowers in cymes, without petal-like bracts; shrubs, fruit blue or white.
Leaves alternate. Fruit blue.......--...------- eee sees eee eee 2. C. alternifolia.
Leaves opposite.

Leaves downy-hairy beneath, with white or rusty brown hairs. Fruit blue.
Leaves broadly oval or rounded, ovate, white-hairy beneath. .....3. C. rugosa.
Leaves ovate or ovate-oblong, with mostly rusty brown hairs beneath.

. 4, C. amomum.

Leaves glabrous beneath, or with closely appressed white hairs.

Branches purple; leaves short-pointed; cymes dense, flat....5. C. stolonifera.
Branches gray; leaves taper-pointed; cymes loosely flowered, convex.
6. C. femina.

1. Cornus florida L. FLOWERING DOGWOOD.

Woods or dry hillsides; abundant. Apr-May. Eastern U. S. (Cynoxylum flori-
dum Raf.) |

The large white bracts are often mistaken for petals. A form with pink bracts is
frequent in cultivation. A flowering branch is shown in plate 35.
g. Cornus alternifolia L. f. BLUE DOGWOOD.
Above the Aqueduct Bridge, May, 1877 (Ward). Eastern N. Amer.
3. Cornus rugosa Lam.
Dodge’s Mill, 1883 (W. P. Conant). Eastern N. Amer. (C. circinata L’Hér.)
4, Cornus amomum Mill.
Low woods and along streams; common. May-June. Eastern N. Amer. (C.
sericea L.; C. stolonifera of Ward’s Flora, in part.)
5. Cornus stolonifera Michx.
Low ground along the upper Potomac; infrequent. Widely distributed in N.
Amer.
6. Cornus femina Mill.
Swamp near Hyattsville, May, 1910 (McAtee). May-June. Eastern U. 8S. (C.
paniculata L’ Hér.)

117. CLETHRACEAE. Sweet alder Family.

1. CLETHRA L.

1. Clethra alnifolia L. SwWEEL ALDER.
Swamps in the Coastal Plain; infrequent; Hollywood Swamp; Powder Mill swamps.
July-Aug. Coastal Plain from Me. to Fla.

118. PYROLACEAE. Shinleaf Family.

Flowers in an umbel; leaves sharply serrate.........--------+-- 1.CHIMAPHILA
Flowers in a raceme; leaves entire or obscurely crenate.....-.--------- 2. PYROLA

FLORA OF THE DISTRICT OF COLUMBIA. 921

1, CHIMAPHILA Pursh.

Leaves variegated with white or light green along the veins, broadest near the base.
1. C. maculata.

Leaves not variegated, broadest above the middle...........-.--- 2. C. umbellata.

1. Chimaphila maculata (L.) Pursh. SPOTTED PIPSISSEWA.
Dry sterile woods; frequent on the Coastal Plain. June-July. Eastern U.S.

2. Chimaphila umbellata (L.) Nutt. PIPSISSEWA.

Dry sterile woods; frequent on the Coastal Plain. July. Eastern N. Amer.; Eur.
The American form has been distinguished as C. umbellata cisatlantica Blake.

2. PYROLA L. S#HINLEAF.

Style straight; flowers all turned to one side,.......------+-+++-+-++- 1. P. secunda,

Style strongly bent downward at base and then curved upward; flowers distributed
around the main axis.

Leaves nearly circular, mostly not over 3 cm. long, shorter than the slender petiole; |

calyx lobes ovate, about 2 mm. long...........++---+e++++- 2. P. chlorantha.,
Leaves mostly 4-6 cm. long; calyx lobes ovate or oblong.
Leaves orbicular, thick; calyx lobes oblong, 3 mm, long....... 8. P. americana,

Leaves elliptic, thin; calyx lobes triangular-acute, scarcely 2 mm. long.
4, P. elliptica.

1, Pyrola secunda L. °

Rich woods; above the fall line; infrequent. June. Northern N. Amer., south
to Va.
2. Pyrola chlorantha Swartz.

Dry pine woods; infrequent. June. Northern N. Amer., south to Va,
8. Pyrola americana Sweet.

Moist or sandy woods; frequent. June. Eastern N. Amer. (P. rotundifolia of
Ward’s Flora.)
4, Pyrola elliptica Nutt.

Dry woods; infrequent; the only specimens seen collected by Ward on the Carroll
Estate (Rock Creek Park). June. Northern states, south to Va.

119. MONOTROPACEAE. Indian pipe Family.

Petals united... 2.2.2... ee eee ee eee eee eee e erences 1, MONOTROPSIS.

Petals separate.
Plants 1-flowered, glabrous, usually waxy white (black in drying).
2. MONOTROPA.

Plants several-flowered, pubescent, tawny or pinkish.............-8. HYPOPITYS.
1. MONOTROPSIS Schwein. .

1. Monotropsis odorata Ell. SWEET PINESAP.
Rich woods; rare; Conway station, near Woodwardville, just beyond our limits
(Waite, April 21,1912). Md. to N.C.
The flowers are fragrant.

2, MONOTROPA L.

1, Monotropa uniflora L. INDIAN PIPE.
Rich woods; frequent. June-Sept. Widely distributed in N. Amer.; also in Asia.
The flowers are drooping, but the fruit is erect. The plants are rarely pink.

222 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

3. HYPOPITYS Adans.

1, Hypopitys lanuginosa (Michx.) Raf. PINEsAP,
Rich woods; infrequent. July-Sept. Eastern N. Amer. (Monotropa hypopitys
of Ward’s Flora.)
The plants are somewhat fragrant. A colony of plants in flower is shown in
plate 36.

120. ERICACEAE. Heath Family.

Leaves evergreen, thick and leathery, persistent in winter.
Plants prostrate or very low, not more than 15 cm. high; fruit fleshy, edible.

Plants prostrate, the stems rooting; leaves entire, with a bitter taste, rough-hairy
beneath; flowers borne in clusters at the ends of the branches; fruit green,
splitting open and exposing the white pulp.............. 1. EPIGAEA,

Plants with shallow rootstocks, sending up stems 6-10 cm. high; leaves with a
few bristle-tipped teeth, with aromatic taste, glabrous beneath; flowers
solitary in the leaf axils; fruit red, not opening.......... 2. GAULTHERIA.

Plants erect, 20 cm. high or more; fruit dry, inedible,

Larger leaves 3-10 cm, long or smaller; winter flowering buds in branched clusters
in the axils of the upper leaves; corolla with 10 small pockets about half
way from the base, these holding the 10 stamens bent back by the anthers;
style straight, the flower not one-sided; pods broader than long..8. KALMIA.

Larger leaves 12-15 cm. long; winter flowering buds solitary at the ends of the
branches; corolla without pockets, the stamens not sprung back; style
curved, the flower one-sided; pods longer than broad.

. . 4. RHODODENDRON.
Leaves deciduous in winter, thin, not leathery.

Flower clusters from solid winter buds 5 mm, or more in diameter borne at the
ends of the branches; corolla 2.5-4 em. long, with slender tube and widely
spreading lobes; stamens and style conspicuously protruding; pods at ma-
turity 3-5 times as long as broad......................--.... 5. AZALEA,

Flower clusters from solid winter buds much less than 5 mm, in diameter and borne
along the sides of the branches, or from racemes expanded in autumn and
remaining exposed over winter; corolla less than 1.5 cm. long, narrowest at the
mouth; stamens never protruding; pods less than twice as long as broad.

Corolla about 3 mm. long, about as broad as long, covered with short appressed
hairs; leaves with appressed hairs on both surfaces; pods with short ap-
pressed hairs............. 00.00.00 cece cece cece cece cece cece 6. XOLISMA.

Corolla 6-10 mm. long, much longer than broad, glabrous or slightly glandular;
leaves with hairs (if present) not appressed; pods glabrous.

Leaves entire; flowers in short clusters from solid winter buds; filaments with
an S-shaped bend near the middle, hairy, the anthers without bristles;
pod longer than broad, narrowed toward the apex....... 7. NEOPIERIS.

Leaves minutely serrate; flowers in long one-sided racemes formed in autumn
and remaining exposed over winter; filaments straight, glabrous, each
anther tipped with,4 bristles; pod broader than long, depressed at the apex.

8. EUBOTRYS.
1, EPIGAEA L.
1.£Epigaea repens L. TRAILING ARBUTUS,

Dry or moist banks and woods. March-Apr.; fr. June. Eastern N. Amer.
A flowering plant is shown in plate 37B.

2. GAULTHERIA L.
1. Gaultheria procumbens L. WINTERGREEN.
Moist banks or woods; widely scattered but rare. J une—July; fr. in autumn, per-
sisting through winter. Eastern N. Amer.
Also known as checkerberry.

FLORA OF THE DISTRICT OF COLUMBIA. 223

8. KALMIA L.

Leaves commonly 2-3.5 cm. wide, usually acute, alternate but clustered near the
ends of the young twigs; corolla 1.5-2.5 cm. broad, white or pink; ripe pods 5-7

mm. thick, on erect pedicels.............02..000ccceeececeeeeee. 1. K. latifolia.
Leaves less than 1.8 cm. wide, usually obtuse, in whorls of 3; corolla 7-12 mm. broad,
magenta-pink; pods 2-4 mm. thick, on recurved pedicels... .. 2. KE. angustifolia,
1. Kalmia latifolia L. MOUNTAIN LAUREL.

Woods; common. May-June. Eastern N. Amer.
A laurel thicket is shown in plate 38; the flowers are shown in plate 39.

2. Kalmia angustifolia L. SHEEP LAUREL.
Swamps, northeastward; infrequent. May-June. Eastern N. Amer.

4. RHODODENDRON L.

1. Rhododendron maximum L. RHODODENDRON.
Ravines along the upper Potomac; very rare. J une—July. Eastern N. Amer.

5. AZALEA L.

Flowers pink, or rarely white, opening in late April or early May, before or with the
leaves; coarse hairs on the outside of the corolla tube usually without glands;
leaves not glaucous beneath; scales of the winter flowering buds usually glabrous
‘outside, the margins ciliate.........0...0.00-c0ccecceeeeeceee ee. 1. A. nudiflora.
Flowers usually white, sometimes pink, opening in June or late May, after the growth
of the leaves; coarse hairs on the outside of the corolla tube always gland-tipped;
leaves often glaucous beneath; scales of the winter flowering buds usually with
satiny white hairs outside, besides the hairs of the Margins........ 2. A. viscosas

1, Azalea nudiflora L. PINK AZALEA.
Dry woods and fields; common. Apr.-May. Eastern U. 8S. (Rhododendron
nudiflorum Torr.)
2. Azalea viscosa L. SWAMP AZALEA.
Swamps, northeastward; frequent. May-June. Eastern U. 8. (Rhododendron vis-
cosum Torr.)
A very variable species, several forms of which have been named. In A. viscosa
glauca (Michx.) A. Gray the leaves are glaucous beneath; in A. viscosa nitida (Pursh)
A. Gray they are green on both sides. Both these forms occur in our region.

6. XOLISMA Raf.

1. Xolisma ligustrina (L.) Britton.
Swamp or woods; common. June. Eastern U. 8. (Andromeda ligustrina Muhl.;
Lyonia ligustrina DC.)
7. NEOPIERIS Britton.

1. Neopieris mariana (L.) Britton. STAGGER-BUSH.
Swamps or dry or moist woods, Rock Creek and eastward ; common. May-June.
Eastern U.S. (Andromeda mariana L.; Lyonia mariana D. Don.)

8. EUBOTRYS Nutt.

1. Eubotrys racemosa (L.) Nutt. SWEETBELLS.
Swamps and dry or moist woods; frequent. May-June. Eastern U.S. (Leucothoe
racemosa A. Gray.)
The winter buds are crimson and conspicuous.

994 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

121. VACCINIACEAE. Blueberry Family.

Lower surface of the leaves covered with minute wax globules, these conspicuous
under a lens; calyx lobes with sessile or stalked glands; seeds 10, arranged in a
ring, surrounded by a bony covering at maturity.......-.--- 1. GAYLUSSACIA.

Lower surface of the leaves without wax globules; calyx lobes without glands; seeds
numerous, not in a ring, lying naked in the pulp of the berry.

Stamen tips projecting from the mouth of the corolla, each anther with 2 spurlike
appendages; bracts of the inflorescence green, persisting until the maturity of
the fruit; pedicel not jointed.....--.---------e-eeee eee 2. POLYCODIUM.

Stamens included within the corolla, the anthers not appendaged; bracts deciduous
after flowering; pedicel jointed to the base of the flower......3. VACCINIUM.

1. GAYLUSSACIA H. B. K. Huck LeBerry.

Leaves somewhat glaucous beneath, without wax globules on the upper surface;
young twigs glabrous; corolla 3-4 mm. long; filaments glabrous; berry light blue,
with a dense bloom, usually much shorter than the pedicel.......1. G. frondosa.

Leaves green, with wax globules or stalked glands on both surfaces; young twigs
pubescent; corolla 5-7 mm. long; filaments hairy; berry black and shining, or
blue with a usually thin bloom, commonly equaling or longer than the pedicel.

Bracts about half as long as the pedicels, deciduous after flowering; ovary, and
usually the bracts and pedicels, with sessile wax globules; corolla red, about
5 mm. long, 2-3 times as long as broad; berry glabrous........--- 2. G. baccata.

Bracts equaling or longer than the pedicels, persistent in fruit; ovary, bracts, and .
pedicels with stalked glands; corolla white, about 7 mm. long, 1-1.5 times as
long as broad; berry hairy........-----2--+-+--+eree eerste ceee 3. G. dumosa.

‘1, Gaylussacia frondosa (L.) Torr. & Gray. DANGLEBERRY.
Swamps or dry or moist woods, chiefly eastward; common. May; fr. July. Eastern
U.S.

2, Gaylussacia baccata (Wang.) K. Koch. BLACK HUCKLEBERRY.
Dry or moist woods or hillsides; common. May; fr. June-July. Eastern N. Amer.
G. resinosa Torr. & Gray.)
8. Gaylussacia dumosa (Andr.) Torr. & Gray. DWARF HUCKLEBERRY.
Swamps and low woods, northeastward ; infrequent. May-June; fr. July-Aug. East-
ern N. Amer. (G. dumosa hirtella A. Gray.)

2. POLYCODIUM Raf.

1. Polycodium stamineum (L.) Greene. DEERBERRY.
Dry or moist woods; common. May-June; fr. J uly-Sept. Eastern U.S. (Vaccin-
ium stamineum L.)
Sometimes known as hog huckleberry. A flowering branch is shown in plate 40.

3. VACCINIUM L. BLUEBERRY.

Plants usually 25-60 cm. high, forming patches by means of rootstocks; bark remaining
green and smooth for several years; leaves usually minutely serrate and hairy on
the margins, 2.5-4 cm. long; corolla little or not at all narrowed at the mouth
when fully expanded .......--.------+++ 2-2-2 eee eee ee ceecrcee 1. V. vacillans.

Plants erect shrubs, commonly 1-2 meters high; bark early splitting and turning
brown; leaves usually entire and 4-7 cm, long; corolla distinctly narrowed at the
mouth, even when fully expanded.

Flower (from base of ovary to end of corolla) 5-7 mm, long.
Fruit black; leaves pubescent beneath.....-...-------+++++ 2. V. atrococcum.
Fruit blue; leaves glabrous beneath. ..-......--++--+--++++-- 3. V. caesariense.
Flower 8-10 mm. long. Leaves glabrous and glaucous beneath; berry blue.
4. V. corymbosum.

FLORA OF THE DISTRICT OF COLUMBIA. 225

1, Vaccinium vacillans Kalm. | DRYLAND BLUEBERRY.
Dry fields and woods; common. Apr.-May; fr. July. Eastern U. 8.
2. Vaccinium atrococcum (A. Gray) Heller. EARLY HIGHBUSH BLUEBERRY.
Swamps and low sandy woods; frequent. Apr.—May; fr. July. Eastern N. Amer.
(V. corymbosum of Ward’s Flora.)
3. Vaccinium caesariense Mackenzie.
Swamps and sandy woods of the Coastal Plain. Apr.—May; fr. July. N. J. to Va.
4, Vaccinium corymbosum L. HIGHBUSH BLUEBERRY.
Swamps or ravines; Paint Branch Swamp and near TB; rare. May; fr. July-Aug.
Eastern N. Amer.

122. PRIMULACEAE. Primrose Family.

Leaves all basal, the flowers showy, purple or pink, in umbels, on an erect simple
naked scape; corolla lobes strongly reflexed. Plants perennial.
; 6, DODECATHEON.
Leaves borne chiefly on the flowering stems and branches; corolla lobes erect or spread -
ing.

Ovary partly inferior, obviously united with the calyx tube at maturity, only the
lobes of the calyx free; corolla white. Plants perennial, low and weak; leaves
alternate. .....-.---- 2-2 ee eee eee eee eee eee 1. SAMOLUS,

Ovary distinctly superior, not united with the calyx; corolla pink, scarlet, blue,
or yellow (rarely white in Anagallis.)

Plants low annuals; flowers axillary; capsules circumscissile, the top falling off as
a circular lid.
‘ Leaves opposite, dark-dotted beneath; flowers on pedicels 1-3 cm, long; corolla
longer than the calyx; stamens with bearded filaments.
4, ANAGALLIS,
Leaves alternate, not dotted; flowers sessile or nearly so; corolla shorter than

the calyx; filaments beardless.........---.-------- 5. CENTUNCULUS,
Plants perennial; flowers axillary or not; capsules 2-5-valved. Leaves opposite

or whorled.
Leaves dotted; staminodia (sterile stamens) wanting; filaments united at the
base... ee eee ee eee eee eee ences 2. LYSIMACHIA,
Leaves not dotted; staminodia 5, alternate with the stamens; filaments dis-
tinct or nearly s0...... 2.0... ee eee ee eee eee ee 3. STEIRONEMA.

1. SAMOLUS L. BrRoOKWEED.
1. Samolus floribundus H. B. K.
Moist, mostly alluvial situations; not uncommon along the Canal and the Potomac
from Georgetown to Great Falls, July. Widely distributed in N. Amer. (8S.
valerandi americanus A. Gray.)

2. LYSIMACHIA L. LooskEstTRIFE,

Stems creeping, commonly rooting at the nodes; leaves roundish. .1, L. nummularia.
Stems erect or ascending; leaves lanceolate to oval or ovate.
Flowers axillary, on long filiform pedicels; stems simple, the leaves mostly in whorls

of 4 or 5 (sometimes 3-7).........2.0--- 20 eee eee eee eee eee 2. L. quadrifolia.
Flowers borne in a long terminal small-bracted raceme; stems usually branched, the
leaves opposite or rarely alternate.......-------++++++---++---- 3. L. tarrestris.

69289—19—_15

226 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

1, Lysimachia nummularia L. . MoNnEYWORT,
Moist places, chiefly in alluvial soil; well established at several localities. May-
June. Naturalized from Eur. in the northeastern U. 8.
2. Lysimachia quadrifolia L. CROSSWORT.
Moist or dry open woods, or low meadows or thickets; common, May-June.
Eastern N. Amer.
8. Lysimachia terrestris (L.) B.S. P.
Low moist or marshy situations; not uncommon, especially along the Potomac.
June-July. Eastern N. Amer. (JL. stricta Ait.)
Lysimachia producta (A. Gray) Fernald, a supposed fertile hybrid of the two last
pecies, is intermediate in characters. It is known locally from two collections.

8, STEIRONEMA Raf. LooszstRIFE.

Stem leaves narrowly linear, stiff, prominently 1-nerved, the lateral veins obscure.
1. S. quadrifiorum.
Stem leaves narrowly lanceolate to ovate or oblong, thin, pinnately veined.
Upper leaves with broadly lanceolate to ovate blades; petioles long, copiously long-
ciliate throughout... 2.2.00... 2... e cece e ee eee cece ee ee ee ence 2. S. ciliatum.
Upper leaves with narrowly lanceolate to oblong blades; petioles often not sharply
separated from the blades.

Basal leaves and Jower stem leaves mostly persistent, the blades round to oblong
or oval; stem usually simple; petioles ciliate throughout, the hairs extending
along the basal part of the blade; pedicels mostly shorter than the leaves.

3. S. hybridum.

Basal leaves and lower stem leaves reduced or rarely persistent; etem commonly
branched; petioles ciliate chiefly at or near the base; pedicels usually longer
than the leaves..............-.----- 22-22 e eee eee eee 4. S. lanceolatum.

1. Steironema quadriflorum (Sims) Hitchc.

Moist open places; two or three stations on the Potomac Flats near Chain Bridge;
apparently rare. June-Aug. Northeastern U.S. (S. longifolium A. Gray.)

2. Steironema ciliatum (L.) Raf. FRINGED LOOSESTRIFE,

Low moist thickets, chiefly along the Potomac; common. June-July. Widely dis-
tributed in N. Amer.

3. Steironema hybridum (Michx.) Raf.

Around pools; locally common at Great Falls (both sides of the River) and above
Sandy Landing, but not found elsewhere. June-July. Eastern U.8., west to Ariz.
(S. ciliatum hybridum A. Gray.)

Closely related to S. lanceolatum but, on the basis of local specimens, distinct.

4. Steironema lanceolatum (Walt.) A. Gray.

Low or marshy situations; half a dozen localities, mostly along the lower Potomac;

apparently not uncommon, June-Aug. Eastern U.S.

4. ANAGALLIS L. Pimperne..

1, Anagallis arvensis L. PooR MAN’S WEATHER-GLASS.
Pastures and waste places; several scattered localities. July-Sept. N. Amer.
generally; naturalized from Eur,

5. CENTUNCULUS L.

1. Centunculus minimus L. CHAFFWEED.
Moist soil; uncommon; Woodlawn, and region of Hyattsville and Bladensburg.
June. Eastern U.S. and westward.

FLORA OF THE DISTRICT OF COLUMBIA. 227

6. DODECATHEON L.

1, Dodecatheon meadia L. SHOOTING STAR.
Moist situations, usually in rich open woods; several localities, Corcoran’s Woods,
Glen Echo, Chevy Chase, and near Dead Run. May. Eastern U. 8. ‘

123, DIOSPYRACEAE, Ebony Family.

1. DIOSPYROS L.
1. Diospyros virginiana L. PERSIMMON.
Old fields. May; fr. Oct. Eastern U.S.

124, OLEACEAE, Olive Family,

The commonly cultivated species are the lilac (Syringa vulgaris L.); the golden
bell (Forsythia suspensa Vahl), a shrub with simple leaves, the yellow 4-parted flowers
appearing before the leaves in early spring; and the jasmine or jessamine. The white
jasmine, Jasminum officinale L., has pinnate leaves, and white flowers in summer.
The yellow jasmine, J. nudiflorum Lindl., has trifoliolate leaves and scattered yellow
flowers appearing before the leaves in early spring, the branches drooping or
reclining.

Leaves compound, unequally pinnate; flowers green; fruit linear or oblong, dry,

Winged .... 2... eee e cece eee eee eee eee cece cence tence eeeeeees 1, FRAXINUS.
Leaves simple; flowers white; fruit fleshy.

Leaves lanceolate or oblong, 2-5 cm. long; corolla small, 4-lobed; fruit a 3-sided

1-3-seeded berry...... 2... ee eee eee ee eee eee eee eee e eee eeee 2. LIGUSTRUM.
Leaves oblong, oval, or obovate, 7-14 cm. long; corolla cleft to the base into 4 linear
lobes 2.5 cm. long; fruit a 1-3-seeded drupe............. 3. CHIONANTHUS.

1. FRAXINUS L. Asu.

Lateral leaflets sessile. Leaflets 3-5 pairs, ovate to oblong-lanceolate, sharply serrate,

5-10 cm. long or more, green on both sides; fruit 2.5-4 cm. long, winged all around

Or nearly 60....- 2 eee eee ee eee eee eee eee e een eneee 1. F. nigra.

Lateral leaflets stalked.
Branchlets and petioles glabrous. Fruit 2.5-5 cm. long, terete below.

Leaflets pale beneath, ovate-lanceolate or oblong-lanceolate, glabrous or pubes-
cent, entire or serrate; wing of the fruit 2-3 times the length of the body,
commonly pointed . ........---- 2-22... e eee eee eee 2. F. americana.

Leaflets green beneath, oblong-lanceolate, commonly glabrous beneath, often
wedge-shaped at the base, serrate; wing of the fruit rarely over twice as long
as the body, truncate or emarginate........ 4a. F. pennsylvanica lanceolata.

Branchlets and petioles pubescent or tomentose.

Leaflets pale and pubescent beneath, 7-9, lanceolate, acuminate, commonly

entire; fruit 4-6 cm. long, the wing terminal, 2—4 times as long as the body.
8. F. biltmoreana,

Leaflets green beneath, 5-9, ovate or oblong-lanceolate, entire or serrulate; fruit

4-5 cm. long, the wing decurrent on the terete body, rarely twice as long as

the latter... 0... cece ee eee cece cee eet eee 4. F. pennsylvanica.
1, Fraxinus nigra Marsh. BLACK ASH..
Swamps and along creeks. Apr.-May. Northern states, south to Va.
2. Fraxinus americana L. WHITE ASH.
Moist woods. Apr.-May. Eastern U.S.
3. Fraxinus biltmoreana Beadle. BILTMORE ASH.

Low places and along streams. Apr-May. Pa.toGa. (Included in F. pubescens
by Ward.)

228 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

4, Fraxinus pennsylvanica Marsh. RED ASH.
Moist woods. Apr-May. Eastern U.S. (9. pubescens Lam.)

4a. Fraxinus pennsylvanica lanceolata (Borckh.) Sarg. GREEN ASH.
Swamps and along streams. May. Eastern U.S. (F. viridis Michx. f.)

2. LIGUSTRUM L.
1. Ligustrum vulgare L. PRIVET.
Used for hedges; rarely escaped from cultivation. June. Eur. and Asia.

8. CHIONANTHUS L.

1. Chionanthus virginica L. FRINGETREE.
Swamps, low woods, and along streams, sometimes on rocky hillsides. May; fr. Aug.
Southern states, north to N. J.

125. LOGANIACEAE. Logania Family.

Corolla red outside, yellow within, 2.5-5 cm. long; leaves ovate.......1. SPIGELIA.
Corolla white, about 2 mm. long; leaves linear...............-.- 2. POLYPREMUM.

1. SPIGELIA L.
1. Spigelia marylandica L. INDIAN PINK
Reported by Holm as collected in a moist thicket in the vicinity of Mount Vernon.

Va. to Tex.
2. POLYPREMUM L.

1. Polypremum procumbens L.

Kenilworth, August, 1898 (Steele); reported by Holm from Marshall Hall. South-
eastern U.S. to Mex., and W. Ind.

Probably adventive in the District.

126. GENTIANACEAE. Gentian Family

Leaves all reduced to small scales; corolla 3-4 mm, long, yellowish white. Flowers
on long slender pedicels. .............2..2---- 222222 eee eee eee 1. BARTONIA.
Leaves, at least part of them, normal, with broad blades; corolla 1 cm, long or longer.
Lower leaves reduced to scales, the upper ones broadly wedge-shaped; plants 15
cm, high or smaller, perennial, flowering in the spring; corolla about 1 cm.

long, white or tinged with purple, the tube about as long as the lobes.
2. OBOLARIA.
Lower leaves similar to the upper ones, not reduced, the upper ones never wedge-
shaped; plants usually 20 cm. high or often much larger, flowering in summer

or autumn; corolla or its lobes distinctly over 1 cm. long.

Corolla lobes several times longer than the very short tube, spreading, normally
pink; flowers on long pedicels; plants annual.............. 3. SABBATIA.
Corolla lobes much shorter than the tube, erect or nearly so, greenish white,
blue, or purple; flowers sessile or nearly so; plants perennial. .4, GENTIANA.

1. BARTONIA Muhl.

Corolla lobes very obtuse, sometimes abruptly short-pointed, finely toothed; calyx
lobes nearly as long as the corolla; branches erect.............. 1. B. virginica.
Corolla lobes acute, entire; calyx lobes half as long as the corolla; branches ascending.

2, B. paniculata.
1. Bartonia virginica (L.) B.S. P.

Sphagnum bogs; rare; known definitely from the Terra Cotta and Paint Branch
swamps and the vicinity of the Reform School. July-Aug. Eastern N. Amer.
(B. tenella Muhl.)

FLORA OF THE DISTRICT OF COLUMBIA. 229

2, Bartonia paniculata (Michx.) Robinson.
Sphagnum bogs; rare or probably overlooked. Aug.-Sept. Eastern U.S.

2, OBOLARIA L.
1. Obolaria virginica L. PENNYWORT.
Woods; frequent. March-June. Eastern U.S.

3. SABBATIA Adans. ROsE-GENTIAN.

Corolla 8-12-lobed............2..2222222--2 20222 e ee eee eee ee eeee 1. S.dodecandra.

Corolla 5-lobed.
Branches opposite, sharply angled; leaves broadly ovate, clasping at the base;
calyx lobes shorter than the corolla..................------ 2. S. angularis.
Branches alternate, nearly terete; leaves linear or linear-lanceolate, narrowed! at
the base; calyx lobes equaling or longer than the corolla. ..38. S. campanulata.

1. Sabbatia dodecandra (L.) B.S. P.
Along the Potomac below Alexandria (Titus Ulke). Eastern U. 8.

2. Sabbatia angularis (L.) Pursh.
Dry or moist fields. July-Sept. Eastern N. Amer.
Plants with white corollas are sometimes found.
8. Sabbatia campanulata (L.) Torr.
Low meadow near Falls Church, July, 1888 (C. Knisley). Eastern U. 8. (S.
gracilis Salisb.) .
4, GENTIANA L. GENTIAN.

Corolla greenish white, striped with purple; lower leaves obovate, rounded at the apex;
margins of the calyx lobes and leaves glabrous or nearly so........ 1. G. villosa.
Corolla blue; leaves mostly lanceolate and broadest below the middle, usually very
acute; margins of the calyx lobes and leaves finely hairy.
Corolla rather deeply lobed, the lobes equaling or longer than the toothed plaits
between them.............0 2.202 cee eee eee 2. G. saponaria.

Corolla very shallowly lobed, the lobes small, often shorter than the plaits.
; 3. G. andrewsii.

1, Gentiana villosa L. STRIPED GENTIAN.
Woods or thickets; frequent. Aug.—Oct. Eastern U. 8S. (G. ochroleuca Froel.;
Dasystephana villosa Small.)
2. Gentiana saponaria L. ; BorrtLe GENTIAN.
Low woods and thickets; frequent. Sept.-Oct. Eastern N. Amer. (Dasysteph-
ana saponaria Small.)
8. Gentiana andrewsii Griseb. CLOSED GENTIAN.
Low woods or thickets; rare. Sept.—Oct. Northeastern N. Amer. (Dasystephana
andrewst Small.)
This and the preceding species intergrade, and the two are doubtfully distinct.
Nymphoides peltatum (Gmel,) Britten & Rendle (N. nymphaeoides Britton), float-
ing heart (of the allied family Menyanthaceae), was formerly well established in the
fish ponds, Potomac Park; the ponds have been filled, however, and the station
destroyed. Native of Eur. and Asia.

127. APOCYNACEAE. Dogbane Family.

Plants erect; leaves not evergreen; flowers in branched cymes; corolla 8 mm. long
or smaller, white, greenish white, or pink................ seeeee 1. APOCYNUM.
Plants creeping; leaves evergreen; flowers solitary in the axils of the leaves, on long
slender pedicels; corolla about 2 cm. long, blue.....-........... ...2, VINCA.

230 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

1. APOCYNUM L. Doasane.

The representatives of this genus in our region have been treated at length by
G. 8. Miller.!. His conclusions as to specific limits and the use of specific names
are, however, widely different from those of the present treatment. Besides the
species recognized below, Miller also reports Apocynum androsaemifolium L. as
collected between Sligo Branch and Paint Branch. The writer has seen no speci-
mens of that species, which is distinguished from our others by its large pink corolla
about 8 mm. long.

Leaves perfectly glabrous beneath. Branches opposite; corolla greenish white, the
lobes erect.
Leaves short-petioled, narrowly lance-oblong, very acute, usually less than 2 cm.

wide, often acute at the base; corolla nearly white......... 1. A, cannabinum.
Leaves, at least the lower ones, sessile, broadly oblong or ovate, usually 3 cm. wide
or larger, rounded at the base; corolla greenish.............-. 2. A. sibiricum.

Leaves more or less hairy beneath.
Corolla greenish, the lobes erect; main stem ending abruptly in a cyme of flowers,
the lateral branches continued above; leaves usually densely hairy beneath.
3. A. pubescens.
Corolla white or pinkish, the lobes slightly spreading; branching dichotomous, that
is, the stems forking; leaves densely or only slightly hairy beneath.
Cymes small, rounded; corolla 4-6 mm. long; branches, at least the upper ones,
reddish....... 22.2.2 c cece eee cece eee e eee e eee eweceececes 4, A. medium.
Cymes broad, flat-topped; corolla 7 mm. long; branches usually green, ascending.
5. A. speciosum.
1. Apocynum cannabinum L. INDIAN HEMP,

Low ground or in marshes, chiefly along the Potomac; common. May-Aug.
Widely distributed in N. Amer. (A. album Greene.)

A. album was described from plants found along the Potomac. The bark of A.
cannabinum contains a strong fiber, which was used by the Indians for various pur-
poses,
2. Apocynum sibiricum Jacq.

Low woods and fields; frequent. May-Aug. Widely distributed in N. Amer.

A, hypericifolium Ait.)

8. Apocynum pubescens R. Br.

Open woods, thickets, and fields; abundant. June-Sept. Eastern N. Amer.
(A. cannabinum of Miller, not of Linnaeus; A. cannabinum pubescens DC.; A. canna-
binum puberulum Bég. & Bel.; A. nemorale Miller; A. cannabinum nemorale Fernald.)

The type of A. nemorale was collected at the Virginia end of the Chain Bridge.

. Apocynum medium Greene.

Dry fields; frequent. June-Aug. Northeastern N. Amer. (A. wrceolifer Miller;
A, milleri Britton; A. pseudomedium Bég. & Bel.)

The type of A. urceolifer was collected at Capital View Park; that of A. millert
also is from our region.

5. pocynum speciosum Miller.
Fields and roadsides; frequent. June-July. Range not definitely known.
The type was collected between Silver Spring and Sligo Branch.

2. VINCA L.
1. Vinca minor L. PERIWINKLE.
Roadsides and woods; frequent. Apr. Native of Eur., often cultivated; fre-
quently escaping and becoming naturalized.
Known also as myrtle. White-flowered plants are sometimes found.

Proc. Biol. Soc. Washington 18: 79-90. pl. 2. 1899.

FLORA OF THE DISTRICT OF COLUMBIA. 231

128. ASCLEPIADACEAE. Milkweed Family.

Plants with twining stems, the leaves heart-shaped, long-petioled.
Corolla lobes spreading, reddish brown or greenish; crown a continuous ring or cup
the 5 fleshy divisions more or less fused together; pod smooth and wing

angled or roughened with warty projections.........-.... 1. VINCETOXICUM.
Corolla lobes erect, white; crown of 5 thin flat awned processes; pod smooth, not
strongly angled................0- eee eee eee eee ee eee eee eee 2. GONOLOBUS.
Plants erect or decumbent, never with twining stems, the leaves sessile or short-
petioled.

Leaves mainly alternate; hoods of the crown without horns or other included out-
growths; pod smooth.............2eeee eee cece cece cere eeeees 8. ACERATES.
Leaves mainly opposite or whorled; crown of 5 hoods, each covering a distinct
curved horn-shaped outgrowth; pod smooth or warty.......... 4. ASCLEPIAS.

1. VINCETOXICUM Walt.

Crown a low wavy ring; pods smooth, angled; seeds very dark brown.
1. V. suberosum.
Crown cup-shaped; pods warty, not angled; seeds reddish brown.
Buds conical; corolla lobes linear to strap-shaped, about 15 mm. long; racemes

several to many-flowered .......-.-.-------- eee eens eee eeeee 2. V. obliquum.

Buds elongate-ovoid; corolla lobes elliptic to linear-oblong, about 10 mm. long;
racemes few-flowered.........---.-e-e ee cece cece eee eee eees 3. V. carolinense.

1. Vincetoxicum suberosum (L.) Britton. ANGLE-POD.

Open thickets along the Potomac near Fort Washington (C. P. Smith). July; fr.
Nov. Va. to Fla. (Gonolobus suberosus R. Br.)

This is the only species of this region to which the name ‘“‘angle-pod” is really appli-
cable. The seeds are much darker brown than in any other milkweed of our region.
2. Vincetoxicum obliquum (Jacq.) Britton.

Frequent in thickets near the Potomac. June; fr. Oct-Nov. Southeastern
U.S. (Gonolobus obliquus R. Br.)

The seeds are the shade of reddish brown common to most milkweeds of this
region.

8. Vincetoxicum carolinense (Jacq.) Britton.

Occasional in thickets south and east of Congress Heights and Alexandria. June-
July. Southeastern U. 8. (Gonolobus carolinensis R. Br.; G. hirsutus of Ward’s
Flora.)

Pods and seeds indistinguishable from those of V. obliquum.

2. GONOLOBUS Michx.

1. Gonolobus laevis Michx. SAND VINE.
Low thickets along the Potomac; common. July-Aug. Southern U. 8. (n-
slenia albida Nutt.; Ampelanus albidus Britton.)

3. ACERATES Ell.

1. Acerates viridiflora (Raf.) Eaton. GREEN-FLOWERED MILKWEED.
Common, though inconspicuous, in the drier open country of our region. July; fr.
Oct.-Nov. Eastern U.S.
4. ASCLEPIAS L. MILKWEED.
Leaves whorled, at least at one of the nodes.

Leaves linear; pods 6-8 cm. long, about 5 mm. thick. Corolla greenish white.
1. A. verticillata.

232 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Leaves broad, not linear; pods 8-12 cm. long, 10-20 mm. thick.
Leaves thin, ovate or ovate-lanceolate, taper-pointed; corolla lobes pink, the
hoods white............. 0.2 cee cee ee eee e ee ee eee 2. A. quadrifolia.
Leaves rather stiff, oval, ovate, or obovate; corolla lobes white, the hoods purplish.
‘ 9. A. variegata.
Leaves scattered or opposite.
Leaves scattered; juice not milky. Corolla pale or dark orange; plants hairy.
4. A. tuberosa.
Leaves mainly opposite; juice milky.
Leaves heart-shaped, clasping, glabrous, wavy-margined. Corolla greenish pur-
ple or decidedly purplish. ...............--...-0--206. 5. A. amplexicaulis.
Leaves sessile or short-petioled, not clasping.
Stems usually much branched above.

Plants glabrous or nearly so; leaves seldom over 2.5 cm. wide; petioles 4-10
min. long; corolla lobes and hoods rose-purple.......... 10. A. incarnata.

Plants soft-hairy throughout; larger leaves commonly over 2.5 cm. wide;
petioles 2-5 mm. long; corolla lobes and hoods pale pinkish.

, 11. A. pulchra.
Stems normally simple.

Pods densely woolly, 2-3 cm. thick, usually warty with soft processes, but
occasionally smooth. Leaves downy beneath; corolla whitish to dull
purple, often fading greenish yellow, the hoods darker....... 6. A. syriaca.

Pods neither woolly nor warty, usually less than 2 cm. thick.

Leaves downy beneath. Corolla lobes and hoods dark purple.
7. A. purpurascens.
Leaves glabrous beneath.
Leaves sessile, long taper-pointed. Corolla lobes and hoods purplish red.
8. A. rubra.
Leaves petioled.
Leaves taper-pointed, ovate; corolla lobes greenish purple, the hoods
white or pink....-..........2..22.0-002206-- 3. A. phytolaccoides.
Leaves oval, ovate, or obovate; corolla lobes white, the hoods purplish.
9. A, variegata.
1. Asclepias verticillata L.
Rather dry open woods; occasional. July-Aug. Widely distributed in N. Amer.

2. Asclepias quadrifolia Jacq.
Rather uncommon on wooded hillsides near the Potomac, above Georgetown.
May-June. Eastern N. Amer.
8. Asclepias phytolaccoides Pursh.
Woodside, June, 1896 (H. W. Oldys). Eastern U. S.
4. Asclepias tuberosa L. BUTTERFLY-WEED. PLEURISY-ROOT.
Frequent in dry open places. June-Aug. Widely distributed in the U. 8. (A.
decumbens L.)
Used in medicine and cultivated as an ornamental plant.
5. Asclepias amplexicaulis J. E. Smith.
Common in open sandy places, especially on the Coastal Plain. May-July; fr.
Aug. Eastern U.S. (A. obtusifolia Michx.)
6. Asclepias syriaca L. COMMON MILKWEED.
Common in open moist ground, especially along highways and in pastures, often
appearing as if an introduced weed. June-July. Eastern N. Amer. (A. cornuti
Decaisne.)
7. Asclepias purpurascens L. PURPLE MILKWEED,
Thickets along the Potomac and Rock Creek; occasional. June. Eastern U.S.

FLORA OF THE DISTRICT OF COLUMBIA. 233

8. Asclepias rubra L. RED MILKWEED.
Occasional in boggy places throughout our area. July. Southeastern U.S.
9. Asclepias variegata L. WHITE MILKWEED.

Occasional in open woods and thickets with much undergrowth, near streams.
June-July. Eastern U.S.

10. Asclepias incarnata L. SwAMP MILKWEED.
Frequent in swamps along and near the Potomac. May-June. Eastern N. Amer.

11. Asclepias pulchra Ehrh. ;
Abundant throughout our area, in moist soil, fields, edges of wet thickets, and

along streams. July-Aug. Eastern N. Amer. (A. incarnata pulchra Pers.)
Closely related to the last, but easily separated where, with us, the two grow together.

129. CONVOLVULACEAE. Morning-glory Family.

Stigma one, capitate, entire or 2 or 3-lobed; annuals or (I. pandurata) perennial from
a fleshy root... -.-. 22... eee ee ee ee ee eee Leceeceeceecee+++++--l. IPOMOEA.
Stigmas 2, linear to oblong or oval; perennials with creeping roots or rootstocks.
2. CONVOLVULUS.
1. IPOMOEA L. MorwniInG-GLory.

The cultivated sweet potato and yam are forms of Ipomoea batatas Poir., and the
very showy and sweet-scented moonflower is I. bona-nox L. Ipomoea quamoclhit L.,
the cypress vine, with pinnate leaves, is rarely found in waste places, escaped from
cultivation.

Stamens and style protruding; corolla deep red, the tube narrow.. Leaves heart-
shaped, entire....-.-. cen wee eee er ccesecaceneccccscscanceseses 1. I. coccinea.
Stamens and style included in the funnelform corolla tube; corolla not bright red.
Stigma entire or 2-lobed; ovary 2-celled; seeds 4; sepals lanceolate or ovate, acute
or obtuse.

Corolla tube purple within, otherwise white, not acutely lobed, much more than
twice as long as the calyx; sepals obtuse, glabrous; root perennial, often
large; seeds with a fringe of long brown hairs on the lateral angles.

2. I. pandurata.

Corolla tube white or pinkish, acutely lobed, only twice as long as the calyx ;
sepals acute, stiff-hairy; annual; seeds glabrous. .....-.----- 3. I. lacunosa.

Stigma 3-lobed; ovary 3-celled; seeds 3-6; sepals long-attenuate, hairy. Annuals,
with glabrous seeds.

Leaves acuminate, entire; flowers and fruits 3-5 in a long-peduncled cluster.

4. I. purpurea.
Leaves acute, 3-lobed; flowers and fruits 1-3 in a short-peduncled cluster.
5. I. hederacea.

1. Ipomoea coccinea L. SMALL RED MORNING-GLORY.

Escaped from cultivation. Aug.-Sept. Native of tropical Amer. (Quamoclit
coccinea Moench.)
2. Ipomoea pandurata (L.) Meyer. WILD POTATO VINE.

Abundant in dry sandy and clay soils generally, trailing in the open or climbing
in thickets. July-Aug. Eastern N. Amer.

The leaves of sterile plants are often 3-lobed.

8. Ipomoea lacunosa L.
Common in moist thickets along the Potomac and in fields and along roadsides at
College Park. Aug.-Sept. Eastern U.S.
4. Ipomoea purpurea (L.) Roth. COMMON MORNING-GLORY,
Common in waste places and roadside thickets. Aug.—Oct. Naturalized from
tropical Amer.

234 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

5. Ipomoea hederacea Jacq.
Waste places and stubble fields. Aug.—Oct. Naturalized from tropical Amer-
(I. nil of Ward’s Flora.)

2. CONVOLVULUS L. BrmnpweEep.

Bracts of the peduncle scalelike, remote from the calyx; stigmas linear; propagating
by creeping roots. ..-. 2.2... eee cence eee cece ence eeeeees 1. C. arvensis.
Bracts of the peduncle leaflike, inclosing the calyx; stigmas oval to oblong; prop-
agating by creeping rootstocks.
Stems short and simple, erect or ascending; leaves oval or obovate, without lobes

at the base or with very small ones..............2.2....2.. 2. C. spithamaeus.
Stems long, trailing or twining; leaves arrow- shaped, with large lobes at the base.
3. C. sepium.

1. Convolvulus arvensis L.
Fields and waste ground, gradually becoming more common. May-Sept. Natu-
Talized from Eurasia.

2. Convolvulus spithamaeus L.
Dry fields and woods; widely scattered but not common. May-June. Eastern N.
Amer.

8. Convolvulus sepium LL.
Thickets, neglected fields, and waysides; abundant. May-Oct. Widely distrib-
uted in N. Amer.
This species is variable and two or more forms may perhaps be separated. The
t ypical form is glabrous or nearly so, with the peduncles elongate and merely 4-
ngled. Var. fraterniflorus Mack. & Bush is more or less pubescent, with shorter and
wing-angled peduncles,

130. CUSCUTACEAE. Dodder Family,
1. CUSCUTA L. Dopper.

Calyx subtended by calyx-like bracts. Flowers sessile; bracts and calyx lobes
minutely ciliolate; corolla tube exceeding the calyx, contracted at the throat;
withering corolla capping the ovoid or oblate capsule, at length deciduous.

5. C. compacta.

Calyx not subtended by bracts.

Flowers sessile or nearly so. Calyx lobes ovate, at least as long as the corolla tube.

Lobes of calyx and corolla 5 each; corolla lobes reflexed; scale! fringes usually
exposed; withering corolla persistent about the globose capsule.

1. C. arvensis.

Lobes of calyx and corolla 4 or 5 each; corolla lobes not reflexed; scales not
exposed; withering corolla persistent at the base of the depressed-globose
capsule.... 2.2... eee eee eens 2. C. polygonorum.

Flowers distinctly pediceled.

Calyx lobes 5 (rarely 4), triangular, acute; corolla tube exceeding the calyx, the
lobes erect, waxy white, their tips incurved; withering corolla surrounding
the depressed-globose capsule..................-eeeceeeeeeeee 3. C. coryli.

Calyx lobes 5, ovate; corolla campanulate, its tube about twice the length of the
calyx, its lobes spreading or reflexed; withering deciduous corolla at first
surrounding the ovoid or globose capsule................... 4. C. gronovii.

1, Cuscuta arvensis Beyr. FIELD DODDER.

On herbaceous plants generally within our range, the species commonly found on
weeds and clover in the vacant lots about Washington. June-Sept. Common
throughout the U.S.

1 The scales are small appendages on the inside of the corolla between the lobes.

FLORA OF THE DISTRICT OF COLUMBIA. 235

2. Cuscuta polygonorum Engelm. SMARTWEED DODDER.
On various herbs in damp situations, particularly Persicaria lapathifolia and P.

pennsylvanica; abundant on these species or the Potomac flats; has been found on

red clover growing near infested Persicaria, June—Sept. Widely distributed in N.

Amer. (C. chlorocarpa Engelm.)

8. Cuscuta coryli Engelm. HAZEL DODDER.

North of Glen Echo park, Oct. 16, 1904 (Mrs. F. H. Hillman). Eastern U.S.
4, Cuscuta gronovii Willd.

Common in moist places, often forming dense yellow areas on low wet ground.
July-Aug. Widely distributed in the U.8.; occurring on many herbaceous plants
and small shrubs.

5. Cuscuta compacta Juss.
Common on low shrubs in woods and along streams. July-Sept. Eastern U.S.

131. POLEMONIACEAE. Phlox Family.

Leaves alternate, pinnate.......-.------e-eee sree reece ere cees 1. POLEMONIUM.
Leaves opposite or fascicled, simple, entire......-----+++-+-+-++rrereee 2, PHLOX.

1. POLEMONIUM L. Jacos’s-LADDER.

1. Polemonium reptans L.
Rich soil in ravines of the upper Potomac; Rock Creek Park; Woodside; Ken-

sington; infrequent. Apr.-May. Eastern U.S.
2. PHLOX L.

Leaves awl-shaped, rigid, crowded; stems creeping, more or less matted, woody at
DaSC. cece eee c cece cece rece cece eee eee ence eee e ence sees ennencenees 1. P. subulata.
Leaves flat, opposite; stems erect or ascending, herbaceous.
Inflorescence a many-flowered panicle; stem leaves 5-10 cm. long.

Panicle pyramidal; leaves often 3 cm. broad; calyx lobes awn-pointed.

2. P. paniculata.

Panicle narrowly oblong or ellipsoid; leaves not much over 1.5 cm. broad; calyx

lobes lanceolate, not awn-pointed.....-------+--+++++++-+-+- 3. P. maculata.

Inflorescence a few-flowered cyme; leaves 3-6 cm. long.
Upper leaves lance-ovate or oblong-lanceolate; stems decumbent at base, with

sterile leafy shoots........-------ee+ee reece eer eee ccrees 4, P. divaricata.

Upper leaves linear or linear-lanceolate; stems erect or nearly so, with no decum-

bent sterile shoots.........-.-. eee e cece newer eee eeereeeeee 5. P. pilosa.

1. Phlox subulata L. Moss PINK. GROUND PINK.
On rocks at Great Falls and Broadwater. Feb.-May; fr. June. Eastern U. 8.

2. Phlox paniculata L. GARDEN PHLOX.

Frequent in moist soil along the Potomac and occasional elsewhere. July—Aug.;

fr. Oct. Eastern U.S.
The perennial garden phlox is derived from this species, and escapes often persist

for years.
8. Phlox maculata L. WILD SWEET WILLIAM.
Occasional in moist woodland along streams; near Laurel and Riverdale; more
common in Va. July-Aug.; sometimes earlier. Eastern U. 8.
4, Phlox divaricata L. BLUE PHLOX.
Frequent in moist woods and thickets along the Potomac and its tributaries. Apr.-
May; fr. June. Eastern N. Amer.
Flowering plants are shown in plate 18A.

236 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

5. Phlox pilosa L.

Evidently rare or overlooked with us; Woodley Park; Herndon; Chevy Chase.
May. Eastern U.S. .

The annual phloxes of gardens are cultivated strains of the.Texan P. drummondii
Hook.

132. HYDROPHYLLACEAE. Waterleaf Family.

Calyx conspicuously enlarged in fruit, without appendages between the lobes, broad

and saucer-shaped; capsule hanging. Leaves pinnately lobed. ...1. NYCTELEA.

Calyx not conspicuously enlarged in fruit, with or without appendages between the
lobes, the lobes narrow and more or less appressed to the usually erect capsule.

Plants perennial, with large long-petioled basal leaves; placenta expanded so as

to line the ovary wall, inclosing the ovules and seeds ; leaves simple or pinnate.

2. HYDROPHYLLUM.

Plants annual, with numerous small, short-petioled or sessile stem leaves but no

conspicuous basal leaves; placentse mere ridges on the ovary wall; leaves

pinnately lobed......... Vee eee eee eee e cece eee eene 3. PHACELIA.

1. NYCTELEA Scop.

1. Nyctelea ambigua (Nutt.) Stand.
Low woods above the fall line. Apr.-May. Eastern N. Amer. (Ellisia nyclelea 1. ;
Macrocalyx nyctelea Kuntze; N. nyctelea Britton.)

2. HYDROPHYLLUM L. Warer.rar.

Leaves pinnately divided or lobed; corolla pale lilac or lavender. ..1. H. virginianum.
Leaves palmately 5-7-lobed, broad, cordate at base; corolla dirty white.
2. H. canadense,
1. Hydrophyllum virginianum L.
Low woods above the fall line. May. Eastern N. Amer.
2. Hydrophyllum canadense L.
Low woods above the fall line. June. Eastern U.S.

38. PHACELIA Juss.

Racemes 2-5-flowered; filaments not hairy; capsule wider than high, constricted
around the 4 large seeds...................... cece eee eeeeee ..l. P. covillei.
Racemes several-flowered, noticeably uncoiling as the flower buds open; filaments
hairy; capsule ovoid, longer than wide.
Leaf lobes or divisions 3-5, the upper leaves not clasping; calyx lobes in fruit 4 mm.

long; corolla lobes entire; seeds 6-12.................------2-. 2. P. dubia.
Leaf lobes or divisions 5-9, the upper leaves clasping; calyx lobes in fruit 6-7 mm.
long; corolla lobes fringed; seeds 4................---eee-eeeee 3. P. purshii.

1. Phacelia covillei S. Wats.
Rich woods along the upper Potomac; more common than either of the following
found in the same region. Apr.-May. Known definitely only from our region. -
The type was collected on Larkspur Island.
2. Phacelia dubia (L.) Small.
Rich woods. Apr.-May. Southeastern U, S. (P. parviflora Pursh.)
8. Phacelia purshii Buckl.
Rich woods. May-June. Eastern U. 8.

FLORA OF THE DISTRICT OF COLUMBIA. 237

133. BORAGINACEAE. Borage Family.

Plants glabrous throughout. Corolla blue, about 2 cm. long........ 4. MERTENSIA.
Plants hairy.
Uppermost leaves long-petioled, the petioles not winged, the blades mostly oval
and rounded at the apex; flowers very small, white, sessile in one-sided spikes.
1. HELIOTROPIUM.
Uppermost leaves sessile or on short winged petioles; flowers on long or short
pedicels.
Flowers not subtended by bracts or leaves, in naked racemes or clusters, or the
lowest flowers sometimes in leaf axils.
Leaves small, rarely 1.5 cm. wide; plants rarely more than 30 cm. high; nut-
lets of the fruit unarmed..........--------------00-0-0-5 5. MYOSOTIS.
Leaves large, most of them over 2 cm. wide and often 3-10 cm. wide or even
larger; plants tall, usually 60-100 cm. high; fruit covered with barbed
SPINeS....... 2... eee eee eee ee eee cece eet cece e ees 2, CYNOGLOSSUM.
Flowers all subtended by bracts, or borne in the leaf axils.
Stems bristly-hairy, the hairs long, stiff, usually whitish; flowers blue, more or
less irregular.
Corolla throat open, the stamens long-exserted; racemes short, arranged in

a long narrow panicle...........--2-.--2222-- ee eee ee eee eee 9. ECHIUM.
Corolla throat closed by scales, the stamens included in the corolla; racemes
mostly long, not panicled..........-.2...2--.---20-+---- 8. LYCOPSIS.

Stems not bristly-hairy, the hairs either appressed or spreading (then very
slender and soft); flowers regular.
Stem leaves mostly long-petioled; fruit armed with barbed prickles.
3. LAPPULA,
Stem leaves sessile; fruit unarmed.
Corolla salverform, the lobes rounded; lateral veins of the leaves incon-

spicuous; style included............. bee eeeeee 6. LITHOSPERMUM.
Corolla tubular, the lobes very acute; lateral veins of the leaves very
prominent; style long-exserted.................. 7. ONOSMODIUM.

1. HELIOTROPIUM L.

1, Heliotropium europaeum L.

Waste ground about Alexandria. July-Sept. Native of Eur.; naturalized in
the eastern U.S.

The garden heliotropes are derived from H. peruvianum L. and H. corymbosum

Ruiz & Pav.
2. CYNOGLOSSUM L.

Stems leafy throughout; leaves all very acute; calyx lobes longer than the fruit;

flowers reddish or white..... 2.2... 0... cece cece ence eee eee eee 1. C. officinale.
Stems naked above; lower leaves rounded or obtuse at the apex; calyx lobes shorter
than the fruit; flowers blue......................-----0---- ..2. C. virginianum.,
1. Cynoglossum officinale L. HovuND’s-TONGUE.

Fields and waste ground; frequent. May-June. Native of Eur.; widely natural.
ized in N. Amer.
White-flowered plants occur occasionally.

2. Cynoglossum virginianum L. WILD COMFREY.
Woods along the upper Potomac and Rock Creek. May-June. Southeastern U.S.
38. LAPPULA Moench.

1. Lappula virginiana (L.) Greene. STICKSEED.
Woods and thickets; frequent. July-Aug. Eastern N. Amer. (Echinospermum
virginicum Lehm.)

288 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

4. MERTENSIA Roth.

1. Mertensia virginica (L.) DC. BLUEBELLS.
Alluvial soil along the Potomac; common. Apr.-May. Eastern N. Amer.
One of the showiest spring flowers. Plants with white flowers are sometimes found
Known also as Virginia cowslip and lungwort.

Asperugo procumbens L., native of Europe, was collected in waste ground about
Washington in 1898.
5. MYOSOTIS L. ForGEetT-ME-NOT.
Myosotis scorpioides L., the common forget-me-not, with blue flowers, was collected
in Washington, June, 1897 (Kearney). Native of Eur. and Asia; often cultivated and
frequently escaping in the eastern U. S.

Hairs of the calyx all straight; plants perennial; flowers blue.............- 1. M. laxa
Hairs of the calyx, at least some of them, with hooked tips; plants annual or biennial;
flowers white.

Calyx not over 5 mm. long at maturity; fruiting racemes with many close flowers,

these on erect or ascending pedicels; nutlets 1.5 mm. long..... 2. M. virginica.

Calyx 6-7 mm. long at maturity; fruiting racemes with few remote flowers, these on

usually recurved pedicels; nutlets 2 mm. long............ 8. M. macrosperma.
1. Myosotis laxa Lehm.

Wet soil, usually along streams or ditches; frequent. May-Aug. Eastern N. Amer.;
alsoin Eur. (MM. palustris of Ward’s Flora.)

Myosotis arvensis (L.) Hill, a blue-flowered species, was collected in the Department
of Agriculture grounds, May, 1905 (House). Eastern N. Amer., perhaps adventive;
also in Eur.

2. Myosotis virginica (L.) B. 8. P. SCORPION-GRASS.

Dry or wet fields and hillsides; frequent. May. Eastern U.8. (M. verna Nutt.)
8. Myosotis macrosperma Engelm.

Wet soil; Congress Heights and along the lower Potomac, May—June. South-
eastern U.S. (M. arvensis of Ward’s Flora; M. virginica macrosperma Fernald.)

6. LITHOSPERMUM L.

Flowers white, about 6 mm. long, mostly in the leaf axils, the corolla tube about as

long as the calyx lobes; plants annual or biennial.............-. 1. L. arvense.
Flowers bright yellow, about 12 mm. long, in short leafy racemes, the corolla tube
much longer than the calyx lobes; plants perennial........ ...2. L. canescens.
1. Lithospermum arvense L. CorRN GROMWELL.

Dry fields and roadsides; common. Apr.-May. Native of Eur.; widely natu-

ralized in N. Amer.
The roots of this and the following species contain a purple dye.

2. Lithospermum canescens (Michx.) Lehm. Hoary PUCCOON.
Woodley Road and near Langley, in 1877 and 1884 (Ward). Eastern N. Amer.
7. ONOSMODIUM Michx.

1. Onosmodium virginianum (L.) DC. FALSE GROMWELL.
Dry hillsides; Terra Cotta, Bladensburg, Difficult Run, and Great Falls. June

Eastern U. 8.

Symphytum officinale L., comfrey, was collected at Woodside, June, 1896 (1. W.
Oldys). Native of Eur. and Asia; sometimes adventive in eastern N. Amer.

Borago officinalis L., borage, was collected at Foundry Run, June, 1885 (A. LZ.
Schott). Native of Eur.; occasionally adventive in eastern N. Amer.

FLORA OF THE DISTRICT OF COLUMBIA. 239

8. LYCOPSIS L.
1. Lycopsis arvensis L. ‘ BuGuoss.
Collected in several places within our area; probably not established. June-
July. Native of Eur. and Asia; occasionally adventive in eastern N. Amer.

9, ECHIUM L.
1. Echium vulgare L. VIPER’S BUGLOSS.
Old fields; occasional. June-July. Native of Eur.; widely naturalized in N.

Amer.
White-flowered plants are sometimes found.

134, VERBENACEAE. Vervain Family.

Plants erect; corolla 5-lobed; fruit composed of 4 nutlets; flowers in long spikes.

1. VERBENA.
Plants prostrate or ascending; corolla 4-lobed; fruit of 2 nutlets; flowers in short
headlike spikes. ... 2... 2... eee eee eee eee eee cece eee eee e eens 2. LIPPIA.

1. VERBENA L.

Leaves deeply lobed; plants annual. Corolla white; fruit in interrupted spikes.
1. V. officinalis.
Leaves merely toothed; plants perennial.
Leaves linear to oblanceolate, broadest above the middle. Corolla purple or blue;

spikes dense, the fruits overlapping....................- 2. V. angustifolia.
Leaves ovate or lanceolate, broadest near the base.
Spikes crowded, dense; corolla blue or pink.............-..--.--- 3. V. hastata.

Spikes slender, interrupted, the flowers not overlapping; corolla white.
4. V. urticifolia.

1. Verbena officinalts L. EUROPEAN VERVAIN.
Waste ground about Georgetown and Alexandria. June-Aug. Native of Eur.;
naturalized in many parts of the U. 8.

2. Verbena angustifolia Michx. NARROW-LEAF VERVAIN.
Open fields; common. July-Aug. Eastern U. 8.
8. Verbena hastata L. BLUE VERVAIN.
Damp soil; frequent. July-Aug. Eastern N. Amer.
4. Verbena urticifolia L. WHITE VERVAIN.
Open fields; frequent. July-Aug. Eastern N. Amer.
2. LIPPIA L.

1. Lippia lanceolata Michx.
Wet flats along the Potomac. July-Aug. Eastern N. Amer. (Phyla lanceolata

Greene.)
135. MENTHACEAE. Mint Family.

Inflorescence composed of dense axillary whorls, compact heads, or close spikes.
Flowers axillary, without conspicuous colored bracts, sessile.
Plants densely white-woolly........... 2.2... e cece eee eee eee 6. MARRUBIUM.
Plants glabrous or hairy, not densely woolly.
Corolla strongly 2-lipped; leaves rounded or cut-lobed.
Upper leaves wedge-shaped at the base, sharply lobed; plants tall, erect.
13. LEONURUS.

Upper leaves heart-shaped or clasping; plants low, often trailing.
12. LAMIUM.

240 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Corolla nearly regular; leaves ovate to lanceolate.
Plants not odorous; fertile stamens 2...........-------- ....23, LYCOPUS.
Plants strongly odorous; fertile stamens 4....-....---------- 24. MENTHA.

Flowers terminal, or terminal and axillary in the uppermost axils, often with con-

spicuous colored bracts.
Bracts broad, much exceeding the flowers, whitish, yellowish, or purplish, very

CONSPICUOUS. .... 2-2 eee eee eee eee ee eee te eeeee 16. MONARDA.
Bracts very narrow or, if broad, the upper ones, at least, not longer than the
flowers.
Flowers in spikes.
Plants soft-downy.
Flowers white, spotted with purple; corolla 2-lipped.........- 8. NEPETA.
Flowers bright blue; corolla seemingly 1-lipped..........----- 1. AJUGA.

Plants glabrous or hairy, but not downy.
Flowers greenish yellow. Spikes long and somewhat slender, but stiff and
dense.... 2.2... cece ce eee ee ee eee eee eee ..---7. AGASTACHE.

Flowers white or purple.
Corolla 2-lipped; spikes thick..........-. .-10. PRUNELLA.
Corolla nearly regular; spikes slender.........-.-----+-- 24. MENTHA.
Flowers in heads, occasionally with whorls in the axils of the upper leaves.
Plants corymbosely branched, stiffly erect. Flower heads often clustered.

21. KOELLIA.
Plants simple or with few branches, often more or less procumbent.
Corolla pale bluish, spotted; fertile stamens 2.......-.--- 17. BLEPHILIA.

Corolla lavender, pinkish, or white; fertile stamens 4.
‘20. CLINOPODIUM.

Inflorescence composed of loosely 1-several-flowered terminal or axillary clusters, of

racemes, or of loose interrupted spikes.

Calyx with a prominent protuberance on the upper side, not toothed. Corolla blue
and white..............00 eee ee eee eee eee eee eeeces 5. SCUTELLARIA.

Calyx without a protuberance on the upper side, toothed.
Flowers in loose 1-few-flowered clusters, axillary or terminal, or both, not in

spikes or racemes.
Corolla regular or nearly so, 5-lobed or cleft.
Calyx equally 5-lobed; stamens scarcely longer than the corolla.
3. ISANTHUS.

Calyx with 3 long and 2 short teeth; stamens greatly exceeding the corolla.
4. TRICHOSTEMA.

Corolla very irregular, 2-lipped.
Flowers mostly terminal, in cymose clusters. Plants corymbosely branched.
22. CUNILA.

Flowers mostly axillary, in few-flowered clusters or solitary.

Leaves coarsely crenate or serrate, large.
_ Leaves reniform or rounded heart-shaped; flowers usually bluish.
9. GLECOMA.

Leaves ovate; flowers white.........-. _a.eeeeeeee-s-19. MELISSA.

Leaves sparingly crenate or dentate, small.
Leaves broadly ovate, mostly rounded at the base; stamens 4.
20. CLINOPODIUM.

Leaves oblong-ovate, acuminate at the base; stamens 2.
18. HEDEOMA.

Flowers in spikes or racemes.

Inflorescence a loose raceme. Flowers yellow; leaves large.
25. COLLINSONIA.

FLORA OF THE DISTRICT OF COLUMBIA. 241

Inflorescence a more or less interrupted spike.
Flowers either nearly regular or seemingly 1-lipped.

Spikes thick; flowers large, seemingly 1-lipped.......---- 2. TEUCRIUM.
Spikes slender; flowers small, nearly regular.......------- 24. MENTHA.
Flowers distinctly 2-lipped.
Plants purple or purplish green........---------+-+-+seee-- 26. PERILLA.
Plants green, not purplish.
Calyx distinctly 2-lipped...........---+-2seseee seer ee eeee 15. SALVIA.

Calyx nearly regular.
Plants white-hairy or canescent.
Flowers large, bright blue.............-.------++-++-+-- 1. AJUGA.
Flowers small, white or purplish. .......-..---------- 8. NEPETA.
Plants puberulent, pubescent, or hirsute, but not whitened.
Leaves narrowly lanceolate, merely puberulent; spikes rather

loosely flowered, continuous.........- 11. DRACOCEPHALUM.
Leaves broader, conspicuously pubescent or hirsute; spikes composed
of interrupted whorls.........----------+-++-++-- 14. STACHYS.
1, AJUGA L.
1. Ajuga genevensis L. BUGLEWEED.

Established in a pasture near Maryland Agricultural College. July. Native of
Eur.; locally established in the middle coastal states.

2. TEUCRIUM L.
1. Teucrium canadense L. Woop-SAGE.
Rich low ground. July-Aug. Eastern U. 8.

3. ISANTHUS Michx.

1. Isanthus brachiatus (L). B.S. P. FALSE PENNYROYAL.
Collected only once, ‘Flats below mill,” Aug. 12, 1877 (Ward). Eastern N. Amer.
(I. coeruleus Michx.)
4. TRICHOSTEMA L.
1. Trichostema dichotomum L. BLUECURLS.
Dry fields throughout the region. Sept.-Oct. Eastern N. Amer.
The common name is not strictly applicable, for a pink-flowered form is fairly

common.
T. lineare Walt. is reported in Brereton’s Prodromus.

5. SCUTELLARIA L. SKULLCAP.

Flowers solitary, axillary, less than 10 mm. long.
Leaves on the middle of the stem broadly ovate, usually dentate, 24.5 cm. long;

nutlets slender-stalked, conspicuously winged...-..--- weeeeeeee 1. S. nervosa.
Leaves on the middle of the stem narrowly ovate or lanceolate, entire or nearly
so, less than 2 cm. long; nutlets short-stalked, wingless.....---- 2. S. parvula,

Flowers in racemes or panicles or, if occasionally solitary, more than 15 mm. long.
Stem leaves all rounded or cordate at the base.

Flowers 5-8 mm. long, in one-sided racemes.....---.----+-+-+-+ 3. S. lateriflora.
Flowers 12-15 mm. long, not in one-sided racemes.
Plants glabrous; leaves thin, not veiny...-.------++-+-++-+2++-- 4. S. saxatilis.
Plants soft-hairy; leaves thick, veiny, rugose.-......-------+-+-+-- 5. S. ovata.
Stem leaves, at least some of them, acute to acuminate at the base.
Stem leaves, except the lowest, entire........--.--+-------++- 6. S. integrifolia.

69289—19——16

242 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Stem leaves crenate, dentate, or serrate.
Inflorescence and lower surface of leaves covered with fine white down.
7. S. incana,
Inflorescence and lower surface of leaves glabrous or merely pilose.
Corolla 12-17 mm. long; leaves somewhat pilose, mostly obtuse.
8. S. ovalifolia.
Corolla 20-25 mm. long; leaves nearly glabrous, acuminate at both ends.

9. S. serrata.
1. Scutellaria nervosa Pursh.

Woods and thickets, probably throughout the region. May-June. Eastern N.
Amer.
A form with entire leaves has been collected,

2. Scutellaria parvula Michx.
Woods and sandy banks; apparently not common. May—July. Eastern N. Amer,
The rootstock are moniliform and tuber-bearing.

8. Scutellaria laterifiora L. MAD-DOG SKULLCAP.
Usually in wet places; chiefly east and south of Washington. July-Sept. Widely
distributed in N. Amer,

4. Scutellaria saxatilis Ridd.

Known only from the rocky wooded banks of the upper Potomac, where it is not
rare, June-Aug. Del. to Ohio and S. C.

The thin heart-shaped stem leaves on slender petioles are a marked character.

§. Scutellaria ovata Hill.
Rocky woods; rare; Difficult Run and Great Falls. June. Southern states, north to
Pa. (S. versicolor Nutt.; S. cordifolia Muhl.)

6. Scutellaria integrifolia L.
Common. June-July. Eastern U, S.
Distinguished by its oblong-lanceolate entire upper stem leaves.
7. Scutellaria incana Muhl.
* Woods and river banks; collected only at Glen Echo. July-Aug. Eastern N.
Amer, (S. canescens Nutt.)

8. Scutellaria ovalifolia Pers.

Perhaps our commonest skullcap, particularly above the fall line. M ay—July, East-
em U.S. (8. pilosa Michx.)

The rather distant, nearly ovate leaves on nearly simple stems form a ready mark of
distinction.
9. Scutellaria serrata Andr.

Fairly common in woods above the fall line. May-June. Eastern U.S.

The handsomest labiate of this region; the large blue and white flowers and bright
green leaves make a brilliant contrast of colors.

S. galericulata L. is listed in Brereton’s Prodromus.

6. MARRUBIUM L.
1. Marrubium vulgare L. HOoREHOUND.
Waste places. June-Aug. Native of Eur. and Asia; widely naturalized in N.

Amer,
7. AGASTACHE Clayt.

1. Agastache nepetoides (L.) Kuntze. GIANT HYSSOP.
Woods along the Potomac. July-Sept. Eastern N. Amer. (Lophanthus nepetoides
Benth.)

8. NEPETA L.
1. Nepeta cataria L. CATNIP.

Fairly common in waste places. July-Septs Native of Eur. and Asia; widely
naturalized in N. Amer.

FLORA OF THE DISTRICT OF COLUMBIA. 243

9, GLECOMA L.

1. Glecoma hederacea L. GROUND IVY.
Common on shady roadsidesand clearings. March-July. Native of Eur. and Asia;

widely distributed in N. Amer. (Nepeta hederacea Trevis.; N. glecoma Benth.)
Gynomonoecious, the perfect flowers being about 14-16 mm. long and the pistillate

flowers about half that length. Abnormal forms, such as double flowers, are not rare.

Moldavica parviflora (Nutt.) Britton was collected in waste ground near U Street
between Seventeenth and Eighteenth Streets, N. W., June 16, 1896 (Steele). Native
farther north and west. (Dracocephalum parviflorum Nutt.)

10. PRUNELLA L.

1. Prunella vulgaris L. HEAL-ALL.
Common in woods and fields. May-Oct. Throughout N. Amer.; also in Eur.
White-flowered forms are not rare.

Prunella laciniata L., native of Eur., was collected as a waif near Aqueduct Bridge,

July 10, 1890 (Coville).

11. DRACOCEPHALUM L.

1. Dracocephalum virginianum L.

Fairly common in scattered localities along the Potomac. July-Sept. Eastern

N. Amer. (Physostegia virginiana Benth.)

D. denticulatum Ait. is listed in Brereton’s Prodromus; this presumably refers to
the lax-flowered form of D. virginianum found here.

12. LAMIUM L.

Upper leaves clasping, crenate-toothed.......-----+-++++++---+++ 1. L. amplexicaule.
Upper leaves petioled, merely crenate......-----+--+++++++erreee+ 2. L. purpureum,
1, Lamium amplexicaule L. HENBIT.

Widely scattered throughout the region in woods and waste places. March-Oct.
Native of Eur.; widely naturalized in N. Amer.
Forms with white or pink flowers are not rare.
2. Lamium purpureum L. DEAD NETTLE.
Department of Agriculture grounds, Soldiers’ Home Park, and near Lock 11, C. &
O. Canal; probably elsewhere in waste ground. Apr.Oct. Native of Eur.; natu-
ralized in eastern N. Amer.
13. LEONURUS L.
1. Leonurus cardiaca L. MoTHERWORT.
Common along the banks of the Potomac. June-Sept. Native of Eur. and Asia;
naturalized in N. Amer.
14. STACHYS L.

Leaves mostly petioled; stems hairy only on the angles.......-------+-- 1. S. aspera.
Leaves mostly sessile; stems at least slightly hairy on sides and angles.
2. S. palustris.

1. Stachys aspera Michx. HrpGE NETTLE.

Moist soil throughout the region. June-Sept. Eastern N. Amer.

The leaves are generally larger, thinner, and more nearly glabrous than in the
next species.
2. Stachys palustris L. WouNpDWORT.

In much the same locations as the preceding species; not common. June—Sept.
Widely distributed in N. Amer.

244 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

15. SALVIA L.

Stems naked or with 1 or 2 pairs of reduced leaves; leaves mostly lyrate-lobed or
pinnatifid, obovate...... 22.2.0. 00002 e cece c eee e eee. 1. S. lyrata.
Stems more or less leafy; leaves broadly ovate, serrate, cuneate or truncate at the base.
, 2. S. urticifolia.
1. Salvia lyrata L. LYRE-LEAF SAGE.
Abundant in woods of the Piedmont Region. May-July. Eastern U.S.
2. Salvia urticifolia L. .
Rather rare in dry woods. Apr.-June. Eastern U. 8.
Salvia verbenacea L. was collected at Ammendale, May 28, 1916 (Brother Arsene).
Native of Eur.; locally established in the northeastern States.

NETTLE-LEAF SAGE.

16. MONARDA L.

Corolla yellowish, spotted with purple.............. cece cece cece 1. M. punctata.
Corolla purplish to dull white, sometimes spotted.
Leaves thin, with spreading pubescence; calyx teeth bristle-pointed.
2. M. clinopodia.
Leaves firm, canescent beneath with minute appressed hairs; calyx teeth with thin
POINTS... 2... cece cece cece cece cece ce cecl eee. 3. M. mollis.

1. Monarda punctata L. . HoRSEMINT.
Common, especially in the Coastal Plain, usually in dry fields. J uly-Oct. East-
ern U. 8.
2. Monarda clinopodia L.
Rather abundant in woods of the Piedmont Region. June-Aug. Eastern U.S.
All specimens referred to M. fistulosa L. are undoubtedly this species, except one
from the Seaman collection, which was probably from outside our range, and one
specimen of M, mollis.
8. Monarda mollis L.
Woodley, Aug. 16, 1899 (Steele). Eastern U. S., west to Colo.
M. didyma L, is listed in Brereton’s Prodromus but it is doubtful if it occurs here
now.
17. BLEPHILIA Raf.
1. Blephilia hirsuta (Pursh) Torr. Woop MINT.
Plummers Island and near Beltsville. J uly. Eastern N. Amer.

18. HEDEOMA Pers.

1. Hedeoma pulegioides (L) Pers. AMERICAN PENNYROYAL.

Common in dry soil, mostly in the Piedmont Region. July-Sept. Eastern N.
Amer.

19. MELISSA L.

1. Melissa officinalis L. GARDEN BALM.

Waste places about Washington. June-Aug. Native of Eur.; widely naturalized
in N. Amer.

20. CLINOPODIUM L.

Flowers in dense clusters; bracts large, conspicuous.......... we eeeeee 1. C. vulgare.
Flowers in loose clusters; bracts small and inconspicuous............... 2. C. nepeta.
1. Clinopodium vulgare L. Basi.

Woods and alluvial banks, mostly in the Piedmont Region. June-Sept. Widely
distributed in N. Amer.; also in Eur. and Asia. (Satureja vulgaris Fritsch; Cala-
mintha clinopodium Benth.)

FLORA OF THE DISTRICT OF COLUMBIA. 245

2. Clinopodium nepeta (L.) Kuntze. BAsIL THYME.
Dry waste places. June-Oct. Native of Eur. and Asia; naturalized in eastern N.
Amer. (Satureja nepeta Scheele; Calamintha nepeta Link & Hoffm.)

Origanum vulgare L., wild marjoram, has been collected a few times in waste places,
but is probably not established. July-Sept. Native of Eur. and Asia; naturalized
in eastern N. Amer,

21. KEOELLIA Moench. BEsE MINT.

Leaves mostly ovate, at most two and one-half times as long as broad.
Flower clusters less than 1.8 cm. thick; leaves rigid, minutely pubescent or glabrate,

usually less than 5 cm. long............ 20.0 e eee ee eee cece ences 1. K. mutica.
Flower clusters 2-5 cm. thick; leaves thin, white-woolly beneath, some of them
7-10 cm. long........ 2.22... e ee eee eee eee 2. K. incana.

Leaves lanceolate to linear, usually 3- 7 times as long as broad or longer.
Flower clusters in dense corymbs; leaves linear or linear-lanceolate.
Calyx teeth slender, rigidly subulate-tipped; leaves linear, usually light green.
3. K. flexuosa.
Calyx teeth triangular, acute; leaves linear-lanceolate, usually darker.

4. K. virginiana.
Flower clusters not in dense corymbs; leaves usually broader.

Heads densely flowered; leaves 6 times as long as broad or longer. .5. K. verticillata.
Heads somewhat loosely flowered; leaves not more than 5 times as long as broad.

6. K. clinopodioides.
1. Koellia mutica (Michx.) Britton.

Low sandy ground in the Coastal Plain region. July-Aug. Eastern U.S. (Pyec-
nanthemum muticum Pers.)

2. Koellia incana (L.) Kuntze.

Apparently common in dry woods and thickets of the Piedmont Region. June-
Sept. Eastern N, Amer. (Pycnanthemum incanum Michx.)

8. Koellia flexuosa (Walt.) MacM.

The most abundant species in our range; seemingly confined to the Piedmont
Region. June—-Aug.- Eastern U. 8S. (Pycnanthemum flecuosum B. 8. P.; P. lini-
folium Pursh.)

4. Koellia virginiana (L.) MacM.

Not common; along the Potomac east of the fall line. Aug.—Oct. Eastern U. S.
(Pycnanthemum virginianum Dur. & Jacks.; P. lanceolatum Pursh.)

5. Koellia verticillata (Michx.) Kuntze.

Wet places throughout the region; not common. July-Sept. Eastern U. S.
(Pycnanthemum torreyi Benth.; P. verticillatwm Pers.)

6. Koellia clinopodioides (Torr. & Gray) Kuntze.

Dry soil in the Piedmont Region. July—-Oct. Eastern U. S. (Pycnanthemum
clinopodioides Torr. & Gray.)

K. aristata (Michx.) Kuntze is listed in Brereton’s Prodromus. As this species is a.
coastal plant, it is likely that the specimens were collected outside our range.

Thymus serpyllum L., creeping thyme, has been collected a few times as an escape:
from gardens. Native of Eur. and Asia; adventive in eastern N. Amer.

22. CUNILA L.

1. Cunila origanoides (L.) Britton. DiITTANY..
Common in open woods and dry sandy fields. Aug-—Oc.. Eastern U.S. (C.
mariana L.)

246 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

23. LYCOPUS L.

Flower whorls bristly with long slender calyx teeth.
Leaves incised or pinnately lobed, at least at the base; corolla about as long as the
02 a 1. L. americanus.
Leaves serrate; corolla twice as long as the calyx...........--.---- 2. L. rubellus.
Flower whorls not bristly, the calyx teeth short and inconspicuous.
Leaves mostly petioled, dark green, firm; root slender, not tuberous-thickened.
3. L. virginicus.
Leaves mostly sessile, light green, thin; root tuberous-thickened..4. L. uniflorus.

1. Lycopus americanus Muhl. WATER .HOREHOUND.
Wet soil; along the upper Potomac. June—Oct. Widely distributed in N. Amer,
(L. sinuatus Ell.)
2. Lycopus rubellus Moench.
Wet soil along the Potomac and some of its tributaries; rarely collected. Aug.-
Oct. Eastern U.S. (L. europaeus integrifolius A. Gray.)
8. Lycopus virginicus L. BUGLEWORT.
Common in swamps and low wet woods throughout our region. Aug.—Oct. Eastern
U.S. (ZL. sherardi Steele.)
4. Lycopus uniflorus Michx.
Rarely collected; found in much the same habitats as the preceding species, chiefly
in the Coastal Plain. Eastern N. Amer.

24, MENTHA L.

Flowers in terminal leafless spikes.

Spikes narrow, interrupted; leaves mostly sessile...............-. ...-1. M. spicata.

Spikes thick, but slightly interrupted; leaves mostly petioled...... 2. M. piperita.
Flowers in axillary whorls.

Upper leaves much reduced in size. ......... 2... eee eee eee eee 8. M. cardiaca.

Upper leaves but slightly reduced......... wee ee eee eee cece eee 4, M. canadensis.
1. Mentha spicata L. SPEARMINT.,

Wet places throughout our region. July-Aug. Native of Eur.; widely natural-
zed in N. Amer. (UM. viridis L.)
2. Mentha piperita L. PEPPERMINT.
Along the Potomac and its tributaries. July-Aug. Native of Eur.; naturalized in
eastern N. Amer.
3. Mentha cardiaca Baker.
Shores of the Potomac; has been collected rarely. Northeastern N. Amer.
Variable in pubescence. Calyx teeth long-subulate.
4. Mentha canadensis L. WILD MINT.

Common along brooks and in moist places throughout our region. July-Oct.
Widely distributed in N. Amer.

25. COLLINSONIA L.

1. Collinsonia canadensis L. CITRONELLA.
Frequent in dry woods of the Piedmont Region. Aug.—Oct. Eastern N. Amer.
The style twisted to one side of the stamens gives the flowers a peculiar lop-sided

appearance.

26. PERILLA L.
1. Perilla frutescens (L.) Britton. PERILDA.

Not rare throughout our region, usually in waste places. July-Oct. Native of
Asia; naturalized in the eastern U.S. (2. ocimoides crispa of Ward’s Flora.)

Ld

}
FLORA OF THE DISTRICT OF COLUMBIA. 247

136. SOLANACEAE. Nightshade Family.

The following species are commonly cultivated: The tomato, Lycopersicon esculen-
tum Mill., the potato, Solanum tuberosum L., the eggplant, S. melongena L.,
Jerusalem cherry, S. pseudo-capsicum L., and petunias, Petunia axillaris (Lam.)
B.S. P., with white flowers, and P. violacea Lindl., with violet-purple flowers. They
may occasionally be found around refuse heaps, but seldom persist.

Plantsshrubby.......----- 22-222 e2ee eee eee cece eee eee eee eee cece eee 1. LYCIUM.
Plants herbaceous (Solanum duleamara shrubby below, the flowering stems her-
baceous).
Fruit inclosed in an inflated calyx.
Calyx split to the base; flowers purple or blue......---....--- 2. PHYSALODES.

Calyx not split, merely toothed; flowers yellow, usually with purple centers.
3. PHYSALIS.
Fruit not inclosed in an inflated calyx. Flowers white, blue, or purple. °
Corolla funnel-shaped, more than 3 cm. long; fruit a spiny capsule ..4. DATURA.
Corolla saucer-shaped; fruit a berry..........-..-.0--e sees ee ee 5. SOLANUM.

1. LYCIUM L.
1. Lycium halimifolium Mill. MATRIMONY VINE.
Fields and waste places; common. May-Aug. Native of Eur.; escaped from culti-
vationinthe U.S. (ZL. vulgare Dunal.)

2. PHYSALODES Boehm.

1. Physalodes peruvianum Kuntze. APPLE OF PERU.
Waste ground near dwellings; uncommon. July-Sept. Eastern U. S.; introduced
from tropical Amer. (Nicandra physalodes Pers.; P. physalodes Britton.)
8. PHYSALIS L. GROUND CHERRY.
Plants annual.
Fruiting peduncles over 2 cm. long; leaves glandular-pubescent, especially along

the veing ..... 2.2... eee eee ee eee eee eneee 1. P. pubescens.
Fruiting peduncles less than 2 cm. long; leaves glabrous or nearly so. .2. P. ixocarpa.
Plants perennial.
Leaves 1.5-2.2 times as long as broad, tapering at both ends.....-.-- 8. P. virginiana.
Leaves 1.2-1.5 times as long as broad, cordate at the base.....- 4. P. heterophylla.

1. Physalis pubescens L.
Sandy soil; not very abundant. July-Sept. Southern states, north to Pa.
2. Physalis ixocarpa Brot.
Waste ground, usually escaped from cultivation; not very common. Sept.—Oct.
Native of Mex. (P. pubescens of Ward’s Flora.)
3. Physalis virginiana Mill.
Open places; not very common. July-Sept. Eastern U. 8.
4. Physalis heterophylla Nees.
Sandy or rich soil; common. July-Oct. Eastern U. 8. (P. viscosa of Ward’s

Flora.
4. DATURA L.

1. Datura stramonium L. JIMSON-WEED.

Waste places and open fields; common. June-Sept. Eastern U. 8. and tropical
Amer.

There are two forms, one with white flowers and green stems, which is the original
D. stramonium, and one with purple flowers and purple stems which has been called
D. tatula L. Both have a very disagreeable odor, especially when crushed. Jimson
is a contraction of Jamestown. Thorn-apple is another common name for plants of
this genus.

s
4
248 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

5. SOLANUM L.

Solanum rostratum Dunal, the buffalo bur, native of the western U. S., was col-
lected at Alexandria by C. L. Pollard, June 15, 1896, and has been reported from
Mount Rainier.

Plants prickly. Flowers white or bluish........................ 1. S. carolinense.

Plants not prickly.
Flowers white; fruit a small black berry; plant not climbing......... 2. S. nigrum.
Flowers purple or blue; fruit a red berry; plant climbing......... 3. S. dulcamara.

1, Solanum carolinense L. HorSE NETTLE.
Common weed in gardens and waste places. May-Sept. Eastern U.S.

2. Solanum nigrum L. NIGHTSHADE.
Shaded woods and waste places; common. July-Sept. Cosmopolitan.

3. Solanum dulcamara L. BITTERSWEET.

Woods or waste places; uncommon. May-Sept. Native of Eur.; escaped from
cultivation in N. Amer.

137. SCROPHULARIACEAE. Figwort Family.

Leaves all or mostly alternate, only the very lowest, if any, opposite or whorled.
Flowers all borne in the axils of the leaves, on long, very slender pedicels, yel-
lowish and purplish. Leaves entire except for lobes at the base; plants very
hairy, prostrate........2....02.. 20-2 e eee eee eee eee eee eeeee 2. KICKXIA.
Flowers all or mostly in spikes or racemes.
Leaves deeply lobed. Flowers yellowish or reddish; plants hairy.

20. PEDICULARIS.
Leaves entire or merely toothed. ,

Corolla spurred, blue or yellow; leaves entire, linear; plants glabrous or

nearly 80......2.. cece ee eee eee eee eee eee e cence eeeen 3. LINARIA.
Corolla saucer-shaped, not spurred, yellow or white; leaves more or less toothed,
‘road; plants more or less hairy or densely woolly....... 1. VERBASCUM.

Z#aves opposite, at least most of them, those of the inflorescence sometimes alternate.
Plants trees. Leaves very large, broadly ovate; flowers violet.. ..7. PAULOWNIA.
rlants herbaceous.

Leaves all entire.
Leaves whorled, broadly oblong; flowers minute, white or purplish, very

irregular......2.2-...2 220.0020 e eee eee eee 13. MICRANTHEMUM.
Leaves opposite, linear; flowers large, showy, purple or rose-colored, nearly
regular... 2.2... 2.002. e ee eee ee eee ee 18. AGALINIS.
Leaves, at least some of them, toothed or lobed, sometimes only very slightly
toothed.

Flowers borne in the axils of the leaves, the subtending leaves not much smaller
than the other stem leaves.
Leaves, at least the upper ones, more or less lobed, sometimes only with
small lobes at the base.
Lower leaves lobed or toothed; corolla yellow; branches of the inflor-
escence with viscid pubescence............. .-.. 17. AUREOLARIA,
Lower leaves entire; corolla purple or white; branches of the inflor-
escence not viscid.
Plants rough-hairy; leaves sessile; corolla nearly regular.
19. OTOPHYLLA.
Plants nearly glabrous, with only minute hairs; leaves short-stalked;
‘olla 2-lipped, the upper lip hooded........ 21. MELAMPYRUM.

FLORA OF THE DISTRICT OF COLUMBIA. 249

Leaves merely toothed or entire, never lobed.
Capsules and ovaries flat, notched at the apex. Flowers blue or white.
14, VERONICA.
Capsules and ovaries neither flat nor notched.
Flowers closely sessile; plants very hairy.....11. SOPHRONANTHE.
Flowers evidently stalked, in some plants the stalks very short, but the

plants then glabrous. ,

Calyx tubular, angled, toothed, the lobes much shorter than the tube,
corolla blue, 2.5 em. long or larger......-.--.----- 8. MIMULUS.

Calyx cleft nearly or quite to the base, not angled; corolla not blue,
much smaller.

Plants more or less pubescent, or sometimes nearly glabrous, the
pedicels then stout and not longer than the calyx; corolla
yellow or whitish; calyx often with 2 bractlets at the base.

10. GRATIOLA.

Plants glabrous; pedicels slender, much longer than the calyx;
corolla purple or purplish; calyx without bractlets.

Upper leaves broad at the base; capsule as long as the sepals or

longer; fertile stamens 2....... wee aareeee 12. ILYSANTHES.
Upper leaves long-tapering at the base; capsule shorter than the
sepals; fertile stamens 4.........--------- 9. MECARDONIA.

Flowers not axillary, or only a few axillary, mostly in spikes, racemes, panicles,
or cymes, the leaves of the inflorescence, if any, much reduced.
Capsules and ovaries flat, notched at the apex......------- 14. VERONICA.
Capsules and ovaries neither flat nor notched at the apex.
Stem leaves whorled, sharply toothed. Flowérs white or bluish, in long,
slender, very dense spikes ..........---------+-+++- 15. LEPTANDRA.
Stem leaves not whorled.
Calyx lobes toothed, very unequal. Leaves lobed, the lobes toothed;
corolla yellow, 1.5-2 cm. long..........------- 20. PEDICULARIS.
Calyx lobes entire, nearly equal.
Calyx lobes very obtuse, much imbricate, the calyx bracted at the
base. Flowers white or pinkish, about 2.5 cm. long; plants gla-

DYOUS. 2... - ee eee eee ee eee tree cette e ee eeees 5. CHELONE.
Calyx lobes mostly acute, little if at ‘all imbricate, the calyx not
bracted.

Corolla yellow, large and showy; leaves often lobed; plants often
very viscid. Calyx lobes as long as the tube or shorter.

17. AUREOLARIA.

Corolla not yellow; leaves never lobed; plants very slightly if at

all viscid.

Jalyx- tubular, the lobes much shorter than the tube; flowers

sessile or nearly so, purplish blue.......--. 16. BUCHNERA.

Calyx not tubular, the lobes longer than the tube; flowers stalked.

Corolla white to purple; leaves sessile...-... 6. PENSTEMON.

Corolla lurid within; leaves petioled ....4. SCROPHULARIA.

1. VERBASCUM L.

Plants very woolly; flowers in dense spikes, yellow..-...-.....--------- 1. V. thapsus.
Plants green, nearly glabrous; flowers in loose racemes, yellow or white.

2. V. blattaria.

1. Verbascum thapsus L. MULLEIN.
Fields and waste ground; common. July-Aug. Native of Eur. and Asia; widely
naturalized in N. Amer.

250 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

2. Verbascum bDlattaria L. MoTH MULLEIN.
Fields and waste ground; common. June-July. Native of Eur,; extensively
naturalized in N. Amer.
2. KICKXIA Dum.
1. Kickxia elatine (L.) Dum.
Fields and waste ground; occasional. July-Sept. Native of Eur.; naturalized in
eastern N. Amer. (Léinaria elatine Mill.)

3. LINARIA Mill.

Flowers yellow; leaves pale green... .........20-- 22 ceccecceececeeeee 1. L. vulgaris.
Flowers blue; leaves bright green............02. 0-00 .cce cee eeeee 2. L. canadensis.
1. Linaria vulgaris Hill. BUTTER-AND-EGGS,

Fields and waste ground; frequent. June-Aug. Native of Eur. and Asia; widely
naturalized in N. Amer. (LZ. linaria Karst.)
The plants have a very marked and characteristic odor.

2. Linaria canadensis (I..) Dum. BLUE TOAD-FLAX,
Dry woods or fields; frequent. May-June. Widely distributed in N. Amer.;
also in S. Amer.
Corolla often much reduced /n autumnal specimens, the flowers being cleistogamous.

4. SCROPHULARIA L.

1. Scrophularia marylandica L. Fiawort.
Woods and thickets; occasional. Aug.-Sept. Eastern U.S. (S. nodosa of Ward’s

Flora.)
5. CHELONE L,

1. Chelone glabra L. TURTLEHEAD.
Swamps; infrequent. Aug.-Sept. Eastern N. Amer.

6. PENSTEMON Mitchell. Brarp-tronaur.

Stems hairy throughout, with usually long hairs; throat of the corolla densely bearded.
1. P. hirsutus.
Stems nearly or quite glabrous, usually with very minute hairs below, the branches of
the inflorescence more or less hairy; throat of the corolla very slightly or not at
all bearded.
Corolla purplish, 2-2.5 cm. long, the tube not enlarged near the base.
2. P. laevigatus.
Corolla white or pinkish, 2.5-3 cm. long, the tube slightly enlarged on one side near
the base... 2.0.0... e eee eee eee eee eee cece eee eee 3. P. digitalis.
1. Penstemon hirsutus (L.) Willd.
Woods and thickets; frequent. May-June. Eastern U.S. (P. pubescens Soland.)
2. Penstemon laevigatus Soland. :
Woods and thickets; frequent. May-June. Eastern U. 8. (P. penstemon Britton.)
8. Penstemon digitalis (Sweet) Nutt.
Woods and thickets; occasional. May-July. Eastern U, §, (P. laevigatus digi-
talis A. Gray.) .
This is not very definitely separated from the preceding species, and probably does
not deserve specific rank,

7. PAULOWNIA Sieb. & Zucc.

1. Paulownia tomentosa (Thunb.) Baill. “MPRESS TREE,
Frequent in waste ground. Native of Japan; common in cultivation and often
escaping.

This is probably the most rapid grower of any tree found in the eastern United States,
sprouts attaining a very large size in a single season. The flower panicles are formed
inautumn. The large showy flowers appear before the leaves,

FLORA OF THE DISTRICT OF COLUMBIA. 251

8. MIMULUS L. MONKEY FLOWER.

Leaves sessile; pedicels longer than the calyx..........---+--+++++++- 1. M. ringens.
Leaves petioled; pedicels shorter than the calyX.... 22.222 eee eee eee eee 2. M. alatus.

1. Mimulus ringens L.

Swamps and along streams; frequent. July-Aug. Eastern N. Amer.
2. Mimulus alatus Soland.

Swamps and along streams; frequent. July-Aug. Eastern U.S.

Mazus japonicus (Thunb.) Kuntze, a small annual with blue flowers, native of
Asia, was collected in the Department of Agriculture grounds in 1895 and 1896.

9. MECARDONIA Ruiz & Pav.

1. Mecardonia acuminata (Walt.) Small. WATER HYSSOP.
Low ground along the Potomac; infrequent. July-Sept. Southeastern U. S.
(Her pestis nigrescens Benth.; Bacopa acuminata Robinson.)

10. GRATIOLA L. HEDGE HYSSOP.

Capsule globose, as long as the pedicel; plants glabrous or nearly 80.
1. G. virginiana.
Capsule ovoid, much shorter than the pedicel; plants finely glandular-hairy.

Leaves lanceolate, mostly 2.5-5 cm. long; stems usually branched; capsule equaling

or slightly longer than the sepals....--....-----++++++-++rrtet> 2. G. neglecta.
Leaves broadly ovate, mostly 1 cm. long or shorter; stems usually simple; capsule
shorter than the sepals..........--------- cece este eee r erect 3. G. viscosa.

1. Gratiola virginiana L.

Wet soil; occasional. May. Southeastern U. 8. and Mex. (G. sphaerocarpa Ell.)
2. Gratiola neglecta Torr.

Wet soil; occasional. May-June. Widely distributed in N. Amer. (G. virginiana
of authors.)

G. aurea Muhl. has been reported from our region, but no specimens have been
seen by the writer.
3. Gratiola viscosa Schwein.

Swamps along the Eastern Branch and Hunting Creek. Aug.Sept. Southeastern
U.S.

11. SOPHRONANTHE Benth.

1. Sophronanthe pilosa (Michx.) Small.

Dry or wet soil, north and east of Washington; occasional. July-Aug. South -
eastern U. 8. (Gratiola pilosa Michx.)

12, ILYSANTHES Raf. FA.sE PIMPERNEL.

Pedicels longer than the leaves; calyx lobes shorter than the capsule..... 1. I. dubia.
Pedicels shorter than the leaves; calyx lobes as long as the capsule or longer.
2. I. attenuata.

1. Llysanthes dubia (L.) Barnhart.
Wet soil along the Potomac; rare. July-Aug. Eastern U. S. (I. gratioloides
Benth.)
2. Ilysanthes attenuata (Muhl.) Small,
Wet soil along the Potomac and Patuxent; frequent. July-Sept. Eastern N.
Amer. (I. gratioloides of Ward’s Flora, in part.)
138, MICRANTHEMUM Michx.

1. Micranthemum micranthemoides (Nutt.) Wettst.
In mud along the Potomac and Hunting Creek. Sept. Southeastern U. 8. (M.
nuttallii A. Gray.)

252 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

14. VERONICA L. SprEpwe tt.

Flowers in racemes in the axils of the leaves. Plants perennial.
Plants glabrous or nearly so, growing in or near water; leaves more than twice as
long as broad; pedicels more than twice as long as the calyx.
Leaves linear or nearly so; capsule longer than the calyx....... 1. V. scutellata.
Leaves ovate or oblong; capsule shorter than the calyx... 0.02. 2. V. americana.
Plants very hairy, growing usually in dry soil; leaves less than twice as long as
broad; pedicels little if at all longer than the calyx.
Leaves sessile; racemes loosely flowered; pedicels as long as the calyx.
3. V. chamaedrys.
Leaves mostly short-petioled; racemes dense; pedicels shorter than the calyx.
4. V. officinalis.
Flowers solitary in the axils of the leaves or in terminal spikes or racemes.
Leaves glabrous.
Plants annual, mostly erect; flowers axillary; leaves oblong....5. V. peregrina.
Plants perennial, the stems more or less creeping and rooting at the joints; flowers
in terminal racemes; leaves oval or rounded............ 6. V. serpyllifolia.
Leaves conspicuously hairy. Plants annual.
Flowers nearly sessile, the pedicels much shorter than the leaves. .7. V. arvensis.
Flowers long-stalked, the pedicels nearly or quite as long as the leaves.
Leaves with 3 or 5 lobes or large teeth, often broader than long. Lobes of the
capsule rounded................0200..0-02-00---00 2. 8. V. hederaefolia.
Leaves with numerous small teeth, longer than broad.
Corolla longer than the calyx; capsule broadly notched. .9. V. tournefortii.
Corolla not longer than the calyx; capsule with a narrow notch at the apex.
10. V. polita.

1. Veronica scutellata L. MARSH SPEEDWELL.
Marshes along the upper Potomac; rare. J uly-Aug. Widely distributed in N,
Amer.; also in Eur. and Asia.

2. Veronica americana Schwein. AMERICAN BROOKLIME,
Along brooks or in pools; region of the upper Potomac; occasional. May-June.
Widely distributed in N. Amer,

8. Veronica chamaedrys L. GERMANDER SPEEDWELL.
Department of Agriculture Grounds. Apr.-May. Native of Eur.; adventive in

eastern N. Amer.

4. Veronica officinalis L. COMMON SPEEDWELL.
Fields and woods; frequent. May-June. Widely distributed in eastern N.

Amer.; in part adventive from Eur. and Asia.

5. Veronica peregrina LL. PURSLANE SPEEDWELL.
Fields and moist ground; common. Apr-May. Widely distributed in N, Amer.;

also in Eur. and Asia.

6. Veronica serpyllifolia L. _ THYME-LEAF SPEEDWELL.
Moist or wet woods; frequent. Apr.-May. Widely distributed in N. Amer. ;

also in Eur. and Asia.

7. Veronica arvensis L. CORN SPEEDWELL.
Fields, woods, and waste ground; common, March-May; sometimes flowering even

earlier. Native of Eur. and Asia; widely naturalized in N. Amer,

8. Veronica hederaefolia L. IvyY-LEAF SPEEDWELL.
Moist woods along the upper Potomac: locally abundant; occasional elsewhere,

March-Apr. Native of Eur. and Asia; naturalized from N. Y. to 8. C,

9. Veronica tournefortii Gmel.
Lawns or waste ground; occasional. March-Apr. Native of Eur. and Asia;

adventive in many parts of N. Amer. (V. buxbaumii Ten.; V. byzantina B. S. P.)

FLORA OF THE DISTRICT OF COLUMBIA. 953

10. Veronica polita Fries.
Lawns and waste ground; frequent. March-May. Native of Eur.

15. LEPTANDRA Nutt.

1. Leptandra virginica (L.) Nutt. CULVER’S-ROOT.
Woods or thickets;. frequent. July-Aug. Eastern U. 8. (Veronica virginica L.)

16. BUCHNERA L.

1. Buchnera americana L. BLUE-HEARTS.
Dry soil; infrequent. May-Sept. Eastern U. 8S.

17. AUREOLARIA Raf. FA.LsE FOXGLOVE.

Plants glabrous throughout or nearly so. Flowers stalked.
Leaves all or nearly all lobed......................... wee eeeeeee 1. A. virginica.
Leaves entire, or the lowest toothed.................22....0----0-- 2. A. laevigata.
Plants viscid-hairy, at least above.
Flowers nearly sessile; corolla glabrous outside; upper leaves entire or with few

short broad lobes........... 2.0.0.2 3. A. villosa.
Flowers long-stalked; corolla hairy outside; leaves all deeply lobed, the lobes
NNAITOW .. 2. ee ce ee eee ene 4. A. pedicularia.

1, Aureolaria virginica (L.) Pennell.

Dry woods near Great Falls and Hyattsville Aug.—Sept. Eastern U.S. (Gerardia
virginica B.S. P;; G. quercifolia Pursh; Dasystoma virginica Britton.)
2. Aureolaria laevigata Raf.

Mouth of Difficult Run, Sept., 1909 (F. W. Pennell). Eastern U. S. (Gerardia
laevigata Raf.; Dasystoma laevigata Raf.)
3. Aureolaria villosa (Muhl.) Raf.

Dry woods and thickets; frequent. July-Aug. Eastern U. 8. (Gerardia flava and
Dasystoma flava of most authors.)
4. Aureolaria pedicularia (L.) Raf.

Dry woods and thickets, north and east of Washington. Aug.-Sept. Eastern U.S.
(Gerardia pedicularia L.; Dasystoma pedicularia Benth.)

.

18. AGALINIS Raf. PurreLe FOXGLOVE.

°

Pedicels shorter than the calyx or but slightly exceeding it............ 1. A. purpurea,
Pedicels twice as long as the calyx or often much longer.

Corolla 2-lipped, 10-18 mm. long, the 2 upper lobes ascending over the stamens
and style, glabrous within at base of upper lobes; seeds dark brown; leaves
linear, usually straight, finely rough-hairy..............-.---- 2. A. tenuifolia.

Corolla not evidently 2-lipped, the lobes all spreading, pubescent within at the
base of the upper lobes; leaves mostly filiform, often curved, glabrous.

Seeds dark brown; corolla 20-25 mm. long, purple......... ceeeeee 3. A. holmiana.
Seeds light brown; corolla 15 mm. long, pink.......... ceeeeeeee 4. A. decemloba.

1. Agalinis purpurea (L.) Britton.

Moist woods and fields; common. Sept. Eastern U.S. (Gerardia purpurea L.)
2.. Agalinis tenuifolia (Vahl) Raf.

Dry woods and fields; frequent. Aug.—Oct. Eastern N. Amer. (Gerardia tenui-
folia Vahl.)
8. Agalinis holmiana (Greene) Pennell.

Dry woods and fields; frequent. Sept.-Oct. Southeastern U. 8. (Gerardia hol-
miana Greene. )

The type was collected at Brookland.

254 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

4, Agalinis decemloba (Greene) Pennell.
Dry woods and fields; frequent. Aug.-Sept. Del. to N. C. (Gerardia decemloba
Greene. )
The type was collected near Brookland.
19. OTOPHYLLA Benth.

1. Otophylla auriculata (Michx.) Small.
Low ground north and east of Washington and near Alexandria. Sept. Eastern
U.S. (Gerardia auriculata Michx.)

20. PEDICULARIS L.

Stems glabrous; stem leaves chiefly opposite, shallowly lobed; capsule about as long

as the calyx... 2222-222 eee eee ene eee ee 1. P. lanceolata.
Stems woolly; stem leaves alternate, deeply lobed or ‘parted: capsule much longer
than the calyx.......-.----.-. wee eee eee eee eee eee eee 2. P. canadensis.
1. Pedicularis lanceolata Michx. SWAMP LOUSEWORT.

Swamps along Hunting Creek. Sept.—Oct. Eastern N. Amer,

2. Pedicularis canadensis L. Woop BETONY.
Woods and thickets; occasional. Apr.-May. Eastern N. Amer., west to Colo.

21. MELAMPYRUM L.
1. Melampyrum lineare Lam. Cow-WHEAT.
Dry woods north and east of Washington. May-Aug. Eastern and northern N.
Amer. (Af. americanum Michx.)

138. BIGNONIACEAE. Bignonia Family.

; 1. BIGNONIA L.
1. Bignonia radicans L. TRUMPET CREEPER.
Woods and thickets: frequent along the Potomac. June-Sept. Eastern U.S. Often
cultivated for ornament. (Tecoma radicans DC.; Campsis radicans Seem.)

Catalpa bignonioides Walt., the catalpa, is common in cultivation and is sometimes
found as an escape. Native of the southern U. 8. In this species the flowers are
thickly spotted within and the lobes are crimped. C. speciosa Warder, with only
slightly spotted flowers and flat lobes, is also in cultivation. C. ovata Don (C. kaemp-
fert Sieb. & Zuce.), a Chinese species with yellow flowers, has been reported as an
escape.

Martynia louisiana Mill., the unicorn plant, has been collected a few times in waste
ground. Native of the western U. S.; sometimes cultivated and escaping. (M.
proboscidea Glox.)

189. OROBANCHACEAE. Broom-rape Family.

The plants of this family are wholly without green coloring.

Stems branched, the branches numerous, ascending, straight, simple, long, and
Slender... 2... eee eee e eee e eee wees 1. LEPTAMNIUM.
Stems not brgnched.
Flowers 1+, solitary on slender scapelike stalks 6-20 cm. long, these rising from the
nearly underground stem............. 0022s eee eee eee ee eee eee 2. THALESIA.
Flowers very numerous, sessile or short-stalked, in dense spikes on the erect stems.
Plants glabrous; stems 2-3 cm. thick, densely covered with overlapping scales;
flowers crowded, extending to the base of the stem....... 38. CONOPHOLIS.
Plants glandular-pubescent; stems about-5 mm. thick, the scales comparatively
few and scattered; flowers more or less crowded, borne on the upper half of
the stem... 2... ee eee ce cee eee eee gee eens 4. OROBANCHE.

FLORA OF THE DISTRICT OF COLUMBIA. 255

1. LEPTAMNIUM Raf.

1. Leptamnium virginianum (L.) Raf. BEECHDROPS.
Parasitic on roots of the beech in moist woods; common. Aug.—Oct. Eastern N.
Amer. (piphagus virginiana Barton.)

2. THALESIA Raf.

1. Thalesia uniflora (L.) Britton. GHOST-PIPES.
Moist woods and thickets; common. May. Eastern N. Amer. (Aphyllon unit-
florum Torr. & Gray.)
A tuft of the plants is shown in plate 37A.

8. CONOPHOLIS Wallr.

1. Conopholis americana (L. f.) Wallr. SQUAW-ROOT.
Rich hilly woods; common. May. Eastern N. Amer.
A tuft of the plants is shown in plate 34A.

4. OROBANCHE L.
1. Orobanche minor J. E. Smith. BROOM-RAPE.

Parasitic on clover; common. May-June. N. J. to Va.; naturalized from Eur.

140. PINGUICULACEAE. Bladderwort Family.

Plants growing in water, the stems creeping or floating, branched. Bracts of the stems

attached by the base.............-----05- wee e cece ence eee 1, UTRICULARIA.
Plants growing in soil, the stems erect, simple.

Bracts of the stems attached by the middle; bracts at the base of the pedicel without

bractlets; calyx not inclosing the capsule................ 2. SETISCAPELLA,
Bracts attached by the base; bracts at the base of the pedicel accompanied by a
pair of bractlets; calyx inclosing the capsule................-. 3. STOMOISIA.

1. UTRICULARIA L. BLapDERWORT.

Stems creeping in the bottom of water; corolla 4-6 mm. long; flowers 1-4 on each

SCAPC..-------- 2-2 - eee eee eee ee ewe eee e eee cence eceseeeeeees 1. U. gibba.
Stems free-floating except for a single point of attachment; corolla 13-20 mm. long;
flowers 6-20 on each scape......------..-- 2-2-2 eee eee ee eee eee 2. U. macrorhiza.

1, Utricularia gibba L.
Pools along the upper Potomac. July-Sept. Eastern N. Amer.

2. Utricularia macrorhiza LeConte. ZIGZAG BLADDERWORT,
Hunting Creek. Aug. Widely distributed in N. Amer. (U. vulgaris of American
authors. )
2. SETISCAPELLA Barnhart.

1. Setiscapella subulata (L.) Barnhart.
Wet sandy soil; occasional. May-July. Eastern U.S. (Utricularia subulata L.)
3. STOMOISIA Barnhart.

1. Stomoisia virgatula Barnhart.
Swamp near Suitland. N.Y. to Miss. (Ubtricularia virgatula Barnhart.)

141. ACANTHACEAE. Acanthus Family.

Flowers in dense long-stalked heads or spikes, small; plants glabrous; leaves linear-
lanceolate.... 0.2... cee eee eee ee ee centre eee ene e ees 1. DIANTHERA,
Flowers borne in the axils of the leaves, large; plants more or less hairy; leaves ovate
or Oblong....... 6... eee eee ee ee eee eee eee eee eee wee cece eee eeces 2. RUELLIA.

256 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

1. DIANTHERA L.
1. Dianthera americana L. WATER WILLOW.

In water; common. June-July. Eastern U.S.
2. RUELLIA L. Ruvuewiua.

Calyx lobes linear-lanceolate, nearly or quite as long as the corolla tube.
1. BR. strepens.
Calyx lobes very narrow, almost bristle-like, usually shorter than the corolla tube.

2. R. caroliniensis.
1. Ruellia strepens L,

Woods or low ground along the upper Potomac, May-June. Eastern U. S.
2. Ruellia caroliniensis (Walt.) Steud.
' Dry or moist woods or thickets; frequent. June-Aug. Eastern U.S. (R. ciliosa
Pursh.)

Most of our material is the form known as R. ciliosa parviflora (Nees) Britton (R.
parviflora Britton), but it seems to differ in no essential character from the typical
form, and scarcely deserves nomenclatorial recognition.

142, PHRYMACEAE. Lopseed Family.

1. PHRYMA L.
1. Phryma leptostachya L. LopsEED,
Banks and thickets; not uncommon. July. Eastern N. Amer.; also in Asia.

143, PLANTAGINACEAE. Plantain Family.
1. PLANTAGO L. Puantain,

Bracts of the spikes much longer than the flowers. Plants copiously pubescent;

leaves linear or nearly so; corolla lobes spreading................ 1. P. aristata.
Bracts shorter than the flowers.

Leaves linear; plants 3-10 cm. high, minutely hairy. Corolla lobes erect and

closed over the fruit........22020. 0.00... cece eee ee eee wee eeeee 2. °P. pusilla.
Leaves lance-elliptic to broadly oval or oval-ovate; plants usually more than 10
em. high.

Leaves copiously hairy. Seeds 2 in each capsule.
Corolla lobes erect in age; leaves obovate or oblong-obovate, obtuse; plants

annual... 0... 2. eee ee ee cece eee ececcceeeees 8. P. virginica.
Corolla lobes spreading or recurved; leaves lance-elliptic, acute or acuminate;
plants perennial,..............0...0.000...000-22022-2000- 4, P. lanceolata.

Leaves glabrous or nearly so, broadly ovate, oval, or rounded-ovate. Corolla
lobes spreading or reflexed; plants perennial.

Ribs, at least the upper ones, of the leaves arising from the midrib; leaves

often cordate at the base; capsule 2 or 4-seeded, dehiscent at the middle.

5. P. cordata.

Ribs of the leaves distinct, none arising from the midrib; leaves never cordate;

seeds 4-18.
Capsule circumscissile near the middle, broadly ovoid.......... 6. P. major.
Capsule circumscissile much below the middle, cylindric... .. 7. P. rugelii.

1. Plantago aristata Michx. BoTtTLe-BRUSH PLANTAIN.

Open fields or dry soil; common, May-July. Central and western U. S.; adven-
tive eastward.

2. Plantago pusilla Nutt.

Two collections of this from Washington are found in the National Herbarium:
one, collected by Tweedy in 1886, is labeled ‘‘Near Washington’’; another was col-
lected by Ward at the southwest corner of the Soldiers’ Home grounds, May 20, 1883.
Eastern U.S.

FLORA OF THE DISTRICT OF COLUMBIA. 257

3. Plantago virginica L.
Open fields; common, Apr.-May. Eastern U.S. to Mex,
4. Plantago lanceolata L. ENGLISH PLANTAIN.
Fields and waste ground; abundant. May-Aug. Native of Eur. and Asia; natu-
ralized nearly throughout the U. S. and southern Can.
Known also as rib-grass.

5. Plantago cordata Lam. HEART-LEAF PLANTAIN.

Sandy shores at and opposite Alexandria, often growing in water; Eastern Branch.
May-Aug. Eastern U.S.

6. Plantago major L. COMMON PLANTAIN.
Moist soil; abundant. June-Sept. Eur. and N. Amer.; probably naturalized
from Eur. in eastern N. Amer.
7. Plantago rugelii Decaisne.
Moist ground; common. June—Sept. Nearly throughout the U. S. and southern
Can.

144, RUBIACEAE. Madder Family.

Planta shrubby; flowers in very dense spheric heads.........+-- 1. CEPHALANTHUS.
Plants herbaceous; flowers never in spheric heads.
Leaves apparently in whorls of 4 or more. Corolla wheel-shaped, white, yellow, or
greenish; calyx lobes obsolete.....-..--+++-++-+++eseeerrercets 2. GALIUM.
Leaves opposite by 2’s.

Fruit a bright red fleshy berry (rarely white); stems slender and creeping, rooting
at the joints; leaves evergreen, long-petioled, the blades nearly or quite as
broad as long. Corolla white.......-----------+e+2+5ee+> 3. MITCHELLA.

Fruit a dry capsule; stems erect, or sometimes procumbent but not rooting at the
joints; leaves not evergreen, the blades usually much longer than broad.

Flowers sessile in the axilsof the leaves; stipules fringed with bristles. Leaves
sessile, linear or narrowly lanceolate; plants annual.........-- 4. DIODIA.

Flowers pediceled; stipules without bristles.
Corolla white; calyx lobes broadly ovate or oval; flowers mostly in dense
clusters in the axils of the leaves.......---------+- 5. OLDENLANDIA,
Corolla bluish purple, pink, or rarely (abnormally) white; calyx lobes linear or
lanceolate; flowers solitary on long slender pedicels or in terminal cymes.
6. HOUSTONIA.

1. CEPHALANTHUS L.

1. Cephalanthus occidentalis L. BUTTONBUSH.
Wet ground and along streams; frequent. June-Aug. Eastern N. Amer.
In some places within our range this is a small tree with well-developed trunk.

Sherardia arvensis L., field madder, was collected in the Soldiers’ Home grounds,
June, 1912 (Titus Ulke). Native of Eur.; locally adventive in the U. 8.

Asperula arvensis L. was collected in waste ground along the river front, Washington,
May, 1898 (Steele). Native of Eur.; rarely adventive in the U.S.

2. GALIUM L. BEDsTRAW.

Fruit covered with straight or hooked hairs.
Leaves in whorls of 6 or 8, bristle-pointed, l-nerved.
Plants annual; stems bristly-hairy on the angles, the hairs turned downward;
leaves linear-oblanceolate to linear.....---------++-++++2++-- 1. G. aparine.
Plants perennial; stems glabrous; leaves elliptic or elliptic-oblanceolate.
2. G. triflorum.

69289—19—_17

~ 958 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Leaves in whorls of 4.
Leaves 1-nerved; stems densely hairy; flowers conspicuously pediceled, yellowish
purple. 0.0.2.0... cece cece eee cece cece eee. 3. G. pilosum,
Leaves 3-nerved ; stems glabrous or nearly so; flowers sessile or nearly so, greenish,
4. G. circaezans.
Fruit glabrous. Plants perennial.
Leaves acute or bristle-pointed, mostly in whorls of 6.
Leaves linear, shining, slightly upward-scabrous on the margins, acute.
5. G. concinnum.
Leaves elliptic to obovate, dull, downward-scabrous, bristle-pointed.
6. G. asprellum,
Leaves obtuse, never bristle-pointed.
Leaves usually all in whorls of 4, linear or nearly so; corolla lobes 4, acute.
7. G. tinctorium.
Leaves mostly in whorls of 6, sometimes in 4’s, spatulate or spatulate-oblong;
corolla lobes usually 3, obtuse....................---....... 8. G. claytoni.

1. Galium aparine L. GOOSE-GRASS,
Wet or moist ground; common. May-June. Nearly throughout N. Amer,; also in

Eur.

2. Galium triflorum Michx. SWEET-SCENTED BEDSTRAW,
Damp woods or alluvial soil: common. July-Oct. Nearly throughout N. Amer,

north of Mex.; alsoin Eur. and Asia.

8. Galium pilosum Ait. Harry BEDSTRAW,
Dry woods or thickets; along the Potomac and at Lanham. June-July. Eastern

U.S.

4. Galium circaezans Michx. WILD LICORICE,
Open or shady woods; common. May—July. Eastern N. Amer.

5. Galium concinnum Torr. & Gray. SHINING BEDSTRAW.
Low woods along the Potomac; common. J une-Aug. Eastern U.S.

6. Galium asprellum Michx. ROUGH BEDSTRAW,
Woods along the Potomac and Hunting Creek. June-Oct. Eastern N. Amer.

7. Galium tinctorium L. ‘ WILD MADDER.

Low ground near Naucks; also collected at several other localities not specified.
May-June. Eastern N. Amer.
8. Galium claytoni Michx.

Swamps north and east of Washington; frequent. J une-Sept. Eastern N. Amer,
(G. trifidum of Ward’s Flora.)

; 3. MITCHELLA L.

1. Mitchella repens L. PARTRIDGE-BERRY.

Woods, especially under pines; common, May-June; fr. in autumn, persisting
until spring. Eastern N. Amer.

The ‘‘double” scarlet berries, as well as the foliage, are very handsome, and large
quantities of the plant are gathered for winter decorations. A form with white fruit
has been found within our range by Titus Ulke.

4. DIODIA L.
1. Diodia teres Walt. Poor-WEED.
Dry or sterile soil; common. J uly-Sept. Eastern U. 8. to Mex.

5. OLDENLANDIA L.
1. Oldenlandia uniflora L.
Low ground near Bennings, August, 1899 (Steele). Eastern U. 8.

FLORA OF THE DISTRICT OF COLUMBIA. 259

6. HOUSTONIA L.

Stems glabrous, very slender; flowers solitary on long slender pedicels; plants spread-
ing by threadlike rootstocks, often forming dense mats......----- 1. H. coerulea.
Stems finely hairy or long-hairy, stout; flowers in cymes; plants tufted, never with
threadlike rootstocks.
Stems minutely hairy; stem leaves linear-oblong or linear-lanceolate; capsules as

high as broad or higher........--------+++-+-++eeceerr ret ceee 2. H. longifolia.
Stems soft-hairy; stem leaves broadly ovate to ovate-oblong or lance-ovate; cap-
gules broader than high...........-..--.------eseeececeeeeeees 3. H. purpurea.

1. Houstonia coerulea L. BLueETs.

Open fields or meadows; common. Apr.-May. Eastern N. Amer.

The flowers are shown in plate 41A.
2. Houstonia longifolia Gaertn.

Woods along the Potomac above Washington; frequent. July-Sept. Eastern
U.S. (H. purpurea longifolia A. Gray.)
8. Houstonia purpurea L.

Woods and fields; common. May-Aug. Eastern U. 8.

145, CAPRIFOLIACEAE. Honeysuckle Family.

The weigelas, Diervilla rosea, D. japonica, and other species, are handsome ornamen-
tal shrubs grown in parks and gardens. Species of Abelia also are cultivated. Dvter-
villa lonicera Mill was collected along Rock Creek (Oliver) many years ago.

Plants herbaceous. Flowers yellowish, greenish, or purplish, borne in the axils of
the leaves....----- 22 eee e eee eee teeter eee eerste retetereree 3. TRIOSTEUM.

Plants woody.
Corolla distinctly long-tubular; vines. Flowers red, or white or pink changing to

yellow.....2---2e00e eee cece eee c terres te ssre sss e ee sr esses 1. LONICERA.
Corolla not long-tubular; erect shrubs or rarely trees.
Leaves pinnate. Flowers white, in large flat cymes.....------- 5. SAMBUCUS.

Leaves simple.
Flowers mostly clustered in the axils of the leaves, white or pinkish.
2. SYMPHORICARPOS.
Flowers in large flat terminal cymes, white..........-------- 4. VIBURNUM.

1. LONICERA L. HoONEYSUCKLE.

A common cultivated bush honeysuckle is L. tatarica L. It has pink or white
flowers, and red fruits in June.

Upper leaves united by their bases around the stem; flowers in terminal spikes, red;

fruit red........---------- cece eee ee ee eee cece eee eeeeeeeeee 1. L. sempervirens.
Upper leaves distinct; flowers in pairs in the upper axils, white or pink, turning
yellow; fruit black........------+-++++eeeeererree ttre setts se 2. L. japonica.

1. Lonicera sempervirens L. TRUMPET HONEYSUCELE.
Occasional in thickets and along fences. May-June; fr. June-July. Eastern U.S.
®. Lonicera japonica Thunb. JAPANESE HONEYSUCELE.

Abundant almost everywhere. May-Oct.; fr. Sept.—Feb. Naturalized from Asia.
The flowers are shown in plate 42.

2. SYMPHORICARPOS Ludw.

Style glabrous; fruit white........--+--+-+++esrrcttee eres rstte tres 1. S. albus.
Style hairy; fruit red........-----.+++eeeee seer eerste rst 2. 8. orbiculatus.

260 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

1. Symphoricarpos albus (L.) Blake. ' SNOWBERRY.
Sparsely escaped from cultivation; Georgetown; Woodley Park. May-July; fr.
July-late winter. Northern U. 8. (8. racemosus Michx.)
Our plants are var. laevigatus (Fernald) Blake,

2. Symphoricarpos orbiculatus Moench. CORALBERRY.

Abundantly escaped from cultivation; old fields, roadsides, and edges of woods.
July-Aug.; fr. Aug.-spring. Northern and western U. 8. (S. vulgaris Michx.; S.
symphoricar pos MacM. )

3. TRIOSTEUM IL. Horse GEnrian.

Leaves united by their bases around the stem. Corolla purplish brown.

1. T. perfoliatum.
Leaves distinct.

Leaves more or less auricled and clasping at the base; flowers dull red.
2. T. aurantiacum.
Teaves narrowed to the merely sessile base; flowers yellowish. .3. T. angustifolium.

1. Triosteum perfoliatum L.

Sparingly distributed in open woods. May-June; fr. July-fall. Eastern U. 8.
2. Triosteum aurantiacum Bicknell.

Corcoran woods and Reno. May; fr. Oct. Northeastern U. 8.
3. Triosteum angustifolium L.

Occasional in damp woods. May-June; fr. July. Eastern U. S.

4. VIBURNUM L.

The snowball, V. opulus sterile DC., is commonly cultivated. The highbush cran-
berry, V. opulus americanum Ait., and the wayfaring tree, V. lantana L., are also
cultivated. The latter, a native of Europe, has ovate leaves; the former, native in
the northern states, has 3-lobed leaves, like the snowball.

Leaves mostly 3-lobed, soft-downy beneath.................... 1. V. acerifolium.
Leaves not 3-lobed.
Leaves with prominent teeth and veins.
Stipules long, linear; leaves usually very short-petioled............ 2. V. affine.
Stipules very small or wanting; leaves usually long-petioled.

Petioles usually glabrous beneath, if hairy the hairs not chiefly clustered;
hairs on lower surface of leaves mostly confined to axils of veins, often
cobwebby, but not chiefly clustered..................... 3. V. dentatum.

Petioles usually densely and lower leaf surface usually more generally hairy,
the pubescence chiefly of clustered hairs.

Leaves of an ovate type, longer than broad, with about 5 pairs of veins.
4. V. scabrellum.
Leaves often orbicular, about as broad as long, the veins more prominent on
the average and more numerous, 7-11 pairs to the leaf.

. wae 5. V. pubescens.
Leaves finely toothed or entire, with inconspicuous veins.

Flower and fruit clusters long-stalked.
Peduncles shorter than the cymes; leaves thin, usually irregularly crenate.
6. V. cassinoides.
Peduncles usually equal to or longer than the cymes; leaves thick, usually
entire... 2.222... eee cee cece cece cece. 7. V. nudum.
Flower and fruit clusters nearly sessile. Leaves oval, finely and sharply serrate.
. 8. V. prunifolium.
1. Viburnum acerifolium IL. ARROW-WOOD,
Common in woods. May-June.; fr. Aug.-winter. Eastern N. Amer.

FLORA OF THE DISTRICT OF COLUMBIA. 261

2. Viburnum affine Bush.

Frequent on rocks and in woods on both sides of the river about Great Falls. May;
fr. July-Sept. Northeastern N. Amer.

Our plant is the pubescent form, V. affine hypomalacum Blake. (V. pubescens of
authors.)
3. Viburnum dentatum L.

Common in moist ground and swamps. May-June; fr. July-winter. North-
eastern U. 8.
4. Viburnum scabrellum (Torr. & Gray) Chapm.

Common; in drier land, fence rows, and edges of woods. June. Southeastern U. 8.
5. Viburnum pubescens (Ait.) Pursh.

Common in copses and fence rows. June; fr. Aug.winter. Eastern U. S. (V.
venosum Britton; V. venosum canbyt Rehder.)

This and the last preceding are closely related to V. dentatum and puzzling inter-
mediate forms occur.
6. Viburnum cassinoides L.

In bogs now or formerly sphagnous; north and east of Washington. May-June;
fr. Aug.-winter. Eastern N. Amer.
7. Viburnum nudum L.

With the last, but also in ordinary swampy or wet places. May-June; fr. Sept.-
May. Eastern U.S.
8. Viburnum prunifolium L. BLAcK HAW.

Abundant in a variety of situations. Apr.—June; fr. July-Apr. Eastern U. 8.

A shrub, or a small tree with trunk as much as a foot in diameter.

6. SAMBUCUS L.
1. Sambucus canadensis L. ELDER.
Abundant in wet places. May-June; fr. July-Aug. Eastern N. Amer.

146. VALERIANACEAE. Valerian Family.

Plants perennial, spreading by slender runners; stem leaves pinnate; corolla very
slender, 1-2 cm. long.......----+-+e2eeerre reeset 1. VALERIANA.

Plants annual; stem leaves narrow, simple; corolla 2-3 mm. long.
2. VALERIANELLA.

1. VALERIANA L. VALERIAN.

1. Valeriana pauciflora Michx.
Shaded alluvial flats; locally common at a few localities along the Potomac from
High Island to Plummers Island, especially on the islands. May. Eastern U. 8.

2. VALERIANELLA Hill. Lams’s LELTUcE. CorN SALAD.

Corolla bluish, the color evident in the subpersistent corollas of fruiting specimens.

Fruit flattened, rounded........----------+eererrrecer crest 1. V. locusta.
Corolla whitish.
Fruits roundish or saucer-shaped, the sterile cells inflated......-- 2. V. woodsiana.

Fruits oblong to ovate in outline.
Fertile cell of the fruit distinctly broader than the sterile one, the fruit triangular

in cross section. .....-..----e-eee eee eee e eerste 3. V. chenopodifolia.
Fertile cell as broad as the sterile ones, the fruit 4-angled in cross section.
4. V. radiata.

1. Valerianella locusta (L.) Betcke.
Damp meadows, old fields, and thickets; not uncommon, especially along the
Potomac. Apr.-May. Naturalized from Eur. (Fedia olitoria of Ward’s Flora.)

262 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

2. Valerianella woodsiana (Torr. & Gray) Walp.

Moist alluvial bottom lands; rare; known only from High Island to Chain Bridge,
May. Eastern U. S.

8. Valerianella chenopodifolia (Pursh) DC.

Moist alluvial soil; rare; reported only from Sandy Landing and the region from
High Island to Chain Bridge. May. Eastern U, S. (Fedia fagopyrum Torr. & Gray.
4. Valerianella radiata (L.) Dufr.

Meadows and low alluvial situations; several scattered localities near the Potomac,
but apparently rare. May. Eastern U. S.

147. DIPSACACEAE. Teasel Family.

1, DIPSACUS L.
1. Dipsacus sylvestris Huds. TEASEL.

Waste places; known only from Great Falls and from the Potomac flats between
Outlet Lock and High Island. July. Naturalized from Eur. in the northeastern U. S-

148. CUCURBITACEAE. Gourd Family.

Leaves deeply 3-7-lobed, the lobes triangular-lanceolate; staminate flowers in narrow
branched racemes; pistillate flowers solitary; fruit large, 5 cm. long, armed with
short bristle-like spines, dehiscent at the 6), a 1. MICRAMPELIS.

Leaves 5-angled or 5-lobed, with shallow lobes; staminate flowers in loose corvmbs or
racemes; pistillate flowers clustered in a head at the end of a peduncle; fruits
small, burlike, sessile, 3-10 in a cluster, indehiscent ............. 2. SICYOS.,

1. MICRAMPELIS Raf.

1. Micrampelis lobata (Michx.) Greene. WILD CUCUMBER.
Damp soil along streams, especially along the Potomac. July-Sept. Eastern N.
Amer. (Lchinocystis lobata Torr, & Gray.)

2. SICYOS L.
1. Sicyos angulatus L. STAR CUCUMBER.
Alluvial thickets along the Potomac and its tributaries. Aug.-Oct. Eastern N.
Amer, ,
The root and seeds are bitter and have diuretic properties,

149. CAMPANULACEAE. Bellflower Family.

Leaves cordate-clasping; corolla saucer-shaped....................1, SPECULARIA,
Leaves sessile or stalked: corolla bell-shaped or saucer-shaped..... 2, CAMPANULA.

1. SPECULARIA Heist. .

1, Specularia perfoliata (L.) A. DC. VENUS’S LOOKING-GLASS.
Sandy fields, dryish slopes, and thickets; common. June. Eastern N. Amer,
(Legouzia perfoliata Britton.) ;

2. CAMPANULA L. BELLFLower.

Stems very slender, weak, usually reclining, downwardly roughened on the angles;
leaves linear-lanceolate, less than 1 cm. wide; flowers less than 1 cm. long,
whitish... 2.22.2... 00.22 e cece cece ee. 1. C. aparinoides.

Stems stout, erect, not roughened ; leaves heart-shaped to oblong or lanceolate, large;
flowers very much larger, blue.

Corolla bell-shaped; flowers borne in a long bracted 1-sided raceme; capsule globose,
opening by pores at the base...... eee e eee en ee ccc eeneaas 2. C. rapunculoides.
Corolla saucer-shaped; flowers borne in a long leafy spike; capsule top-shaped,
opening by pores at the summit............................. 3. C. americana,

FLORA OF THE DISTRICT OF COLUMBIA. 263

1. Campanula aparinoides Pursh. MARSH BELLFLOWER.
Swales and grassy borders of swamps; known from half a dozen localities, but
easily overlooked. July. Eastern N. Amer. .
2. Campanula rapunculoides L.
Old hedgerows and neglected ground; not common. July-Aug. Naturalized from
Eur.
3, Campanula americana L.
Moist alluvial shaded situations; common along the upper Potomac. July. East-
ern N. Amer.

150. LOBELIACEAE. Lobelia Family.

1. LOBELIA L. LoBE Lt.

Flowers bright red (rarely white); corolla tube 2 cm. long or longer..1. L. cardinalis.
Flowers blue; corolla tube 4-15 mm. long.
Stems branched; pods much inflated....-----.--++---2+eeererettcete 2. L. inflata.
Stems usually simple; pods not inflated.
Flowers not over 1 em. long, borne in a very slender, long, wandlike, erect raceme;
larger leaves mostly basal, the upper stem leaves few, reduced, scattered.
3. L. spicata.
Flowers 2-2.5 cm. long, borne in stout, often dense, racemes; stems conspicuously
leafy throughout.

Leaves 5-25 cm. long, thin, acute at both ends, sparingly pubescent, the hairs
few and stiff; flowers 2-2.5 cm. long; calyx with conspicuous deflexed
auricles between the lobes......------++ee+-eeeeerrrt tee 4. L. syphilitica.

Leaves not more than 5 cm. long, thick, obtuse, densely puberulent; flowers
1.5-2 em. long; auricles of calyx short and rounded, if present.

5. L. puberula.
1. Lobelia cardinalis L. CARDINAL FLOWER.
Moist situations, in partial shade; not very common. Aug.-Sept. Eastern N.
Amer.
2. Lobelia inflata L. INDIAN TOBACCO.
Dryish fields and thickets; common. Aug.Sept. Eastern N. Amer.
8. Lobelia spicata Lam.
Damp or dryish situations, usually in thin shade; common. May-June. Eastern
N. Amer. ;
4, Lobelia syphilitica L GREAT LOBELIA.
Low situations, especially near streams; not uncommon. Aug.-Sept. East-
ern U.S.

5. Lobelia puberula Michx.
Moist meadows or open swamps in sandy soil; common, chiefly eastward. Aug.—

Sept. Eastern U.S.
151. CICHORIACEAE.’ Chicory Family.

Flowers blue, purple, or rarely clear white.
Flower heads sessile; pappus of numerous very short, stiff, simple bristles.
1, CICHORIUM.

Flower heads stalked; pappus of long, soft, simple or plumose bristles.
8. LACTUCA.

1 See the explanation of flower structure under Asteraceae (p. 268).

264 CONTRIBUTIONS FROM THE NATIONAL, HERBARIUM.

Flowers yellow or yellowish.
Plants with naked stems, the leaves all at the base of the scapelike peduncles, these
usually bearing each a single head.
Roots bearing tubers; leaves glabrous; bracts all of equal length...2. CYNTHIA.
Roots without tubers; leaves usually more or less hairy; bracts very unequal.

. 4, LEONTODON,
Plants with leafy, usually branched stems,

Bracts all of equal length. Plants annual..... 2.2... 3. KRIGIA.
Bracts very unequal, the lowest much smaller and shorter than the others.
Achenes short-spiny at the apex; flower heads sessile or nearly so; stems at flow-
ering time bearing only a few linear entire leaves.....5. CHONDRILLA.
Achenes never spiny; flower heads conspicuously stalked; stems usually with
humerous well-developed leaves,
Flower heads drooping, their stalks recurved, Pappus pale or dark brown;
plants tall and coarse, the leaves often deeply lobed..6. PRENANTHES.
Flower heads erect, never drooping,
Achenes strongly compressed; teeth of the leaves often tipped with weak

spines,
Flowers 50 or more in each head, yellow, the heads few; achenes not
beaked...... 2. eee, 7. SONCHUS.,
Flowers 6-30 in each head, yellow or blue, the heads usually very numer-
ous; achenes usually beaked at the APeK... el, 8. LACTUCA.
Achenes not compressed ; leaves mostly entire, the teeth, when present, not
spine-tipped.... 2.2... eee eee, 9. HIERACIUM.

1, CICHORIUM L.
1. Cichorium intybus L. Curcory.
Waste and cultivated ground; common. June-Aug. Native of Eur. ; widely natural -
ized in the U. 8.
A form with white flowers is found occasionally, The roots of chicory have often
been used as a substitute for coffee.

Lapsana communis L., nipplewort, was collected about Washington in 1884 and
1915. Native of Eur.; sparingly adventive in the U. 8.

Tragopogon porrifolius L., salsify, was reported by Ward from Uniontown and by
Holm from Eckington. Native of Eur.; commonly cultivated for its edible roots, and
frequently escaping. Known also as oyster plant,

2. CYNTHIA D. Don.

1, Cynthia dandelion (L.) DC. DWARF GOAT’S-BEARD.
Pine woods or open hillsides about Washington and Alexandria; infrequent. May-
June. Eastern U.S. (Krigia dandelion Nutt.; Adopogon dandelion Kuntze.)
The leaves are usually toothed or lobed, but sometimes they are entire.

8. KRIGIA Schreb.
1. Krigia virginica (L.) Willd.
Open fields and on rocks; frequent. Apr.-Aug. Eastern U, 8, (Adopogon caro-
linianum Britton.)

Apargia autumnalis (L.) Hoftm. (Leontodon autumnalis L.), fall dandelion, was col-
lected in the Zoological Park, September, 1897 (W. Hunter); native of Eur. and
Asia; naturalized locally in the northeastern U. S. A. hispida (L.) Willd. (Leontodon
hispidus L.), common hawkbit, native of Eur., was collected at Ammendale, May,
1916 (Brother Arsene).

Hypochaeris radicata L., cat’s-ear, was collected at Ammendale, June, 1916 (Brother
Hyacinth), Native of Eur.; widely naturalized in the U. 8S.

FLORA OF THE DISTRICT OF COLUMBIA. 265

4, LEONTODON L

Achenes greenish brown; heads 3-5 cm. broad; bracts green, the outer ones reflexed,
without cylindric appendages at the tips; pappus white....... 1. L. taraxacum.
Achenes red or reddish brown; heads 2-3 cm. broad; bracts erect or ascending, with
cylindric appendages at the tips; pappus dirty white..... 2. L. erythrospermum.

1. Leontodon taraxacum L. COMMON DANDELION.

Waste ground, open fields, and lawns; very abundant. Apr.June. Native of Eur.
and Asia; naturalized nearly throughout N. Amer.; perhaps native in the western
U.S. (Taraxacum officinale Weber; T. taraxacum Karst.; 7. dens-leonis Desf.)

The plants may be found in flower at nearly any time of the year, even in midwinter
if there are a few warm days. The leaves are much used for “greens.” Plants with
branched scapes occur occasionally; in one collected in the Department of Agriculture
grounds in 1893, the outermost bracts have assumed the form of leaves 1-2.5 cm. long.
2, Leontodon erythrospermum (Andrzej.) Britton. RED-SEEDED DANDELION.

Waste ground; frequent. Apr—Aug. Native of Eur.; widely naturalized in N.
Amer. (Taraxacum erythrospermum Andrzej.)

5. CHONDRILLA L.
1. Chondrilla juncea L. SKELETON-WEED.
Waste and cultivated ground; common. May-Oct. Native of Eur.; naturalized
from Del. to Va.
This plant is often very abundant in Maryland and Virginia, but in spite of the
adaptation of its seeds to dispersal by wind and other means, it has not spread to other
parts of the United States.

6. PRENANTHES L.

Pappus deep reddish brown; involucre glabrous, cylindric........------- 1. P. alba.
Pappus pale brown; involucre usually bearing a few long hairs, the bracts abruptly

spreading above the middle......--...---------- wen ceecceees 2. P. serpentaria.
1. Prenanthes alba L. RATTLESNAKE-ROOT,

Moist or dry woods; common. Sept.—Oct. Eastern U.S. (Nabalus albus Hook.)

The lower leaves vary from ovate and shallowly toothed to hastate or deeply lobed.
29, Prenanthes serpentaria Pursh. LIon’s-FOOT.

Dry or moist woods and fields; common. Aug.-Oct.- Eastern U. 8. (Nabalus
serpentarius Hook.; N. frasert DC.)

The leaves vary as in the preceding species. A form with merely dentate lower
leaves, described as Nabalus integrifolius Cass., is of frequent occurrence.

7. SONCHUS L. Sow THISTLE.

Achenes ribbed and transversely wrinkled; auricles at the base of the stem leaves

ACUTE. cee n ccc cccc cece eee nee e eee cen eee e ence san ecerecssens ..---1. 5. oleraceus.
Achenes ribbed but not transversely wrinkled; auricles of the stem leaves rounded.
2. S. asper.

1. Sonchus oleraceus L.

Waste ground; frequent. June-Oct. Native of Eur.; naturalized in nearly all
cultivated parts of the earth.
2. Sonchus asper (L.) Hill.

Waste ground; frequent. June-Sept. Native of Eur.; naturalized throughout
most cultivated parts of the earth.

266 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

8. LACTUCA L. Letruce.

Achenes rounded at the apex or narrowed into a short stout beak; flowers blue or

white.
Pappus brown. Achenes with a very short beak; leaves usually deeply lobed.
1. L. spicata.
Pappus white.
Achenes distinctly beaked; leaves deeply lobed..... wee eeeeeee 2. L. floridana,.
Achenes not beaked; leaves merely toothed.................---- 3. L. villosa.

Achenes tapering or abruptly contracted to a slender, usually long beak; flowers
usually yellow, sometimes blue.
Teeth of the leaves spine-tipped. Flowers yellow, 6-12 in each head.
Leaves deeply lobed............. we eee cece eens weet e eee eeee 4. L. scariola.
Leaves finely toothed..........0....200 00. c cece eee cece cece ceceee 5. L. virosa.
Teeth of the leaves not spine-tipped.
Leaves hairy or bristly on the veins beneath; flowers blue or purplish.

Stems long-hairy throughout; leaves merely toothed............. 6. L. steelei.

Stems glabrous above; leaves nearly all deeply lobed...........7. L. hirsuta.
Leaves glabrous; flowers yellow.

Leaves entire or lobed, not clasping at the base............ 8. L. canadensis.

Leaves entire or finely toothed, clasping at the base........ 9. L. sagittifolia.

1. Lactuca spicata (Lam.) Hitchc. BLUE LETTUCE.

Woods; Plummers Island and Terra Cotta. Aug. Eastern N. Amer., west to
Colo. (Mulgedium spicatum DC.)

The flowers are usually blue, but in a specimen from Plummers Island (Kearney
133) they are cream-colored.

Lactuca spicata integrifolia (A. Gray) Britton is a form in which most of the leaves
are merely dentate; in the typical form they are usually deeply lobed. The sub-
species has been collected near Langley and St. Elmo.

2. Lactuca floridana (L.) Gaertn. FLORIDA LETTUCE,

Woods or open fields; common. Aug.-Sept. Eastern U. S. (Mulgedium flori-
danum DC.)

8. Lactuca villosa Jacq.

Woods; frequent. Aug.-Sept. Eastern U. 8. (Mulgedium acuminatum DC.)

4. Lactuca scariola L. PRICKLY LETTUCE,

Waste ground; occasional; apparently a recent introduction. Native of Eur. ;
frequently adventive in the U. S., but much less common than the next.

5. Lactuca virosa L. PRICKLY LETTUCE,

Waste ground about Washington. May-—Aug. Native of Eur.; widely naturalized
‘in the U. S., and often a pernicious weed. (L. scariola integrata Gren. & Godr.)

6. Lactuca steelei Britton.

The type was collected at Chevy Chase, Maryland, July 22, 1897 (Steele); found
also at Anacostia and Falls Church. Britton reports the species, doubtfully, from
Del.

7. Lactuca hirsuta Muhl.
Moist woods and thickets; frequent. July-Aug. Eastern N. Amer,
8. Lactuca canadensis L.

Woods and thickets; frequent. June-Aug. Widely distributed in N. Amer.
9. Lactuca sagittifolia Ell.

Woods; occasional. July-Sept. Eastern N. Amer., west to Idaho. (L. integrifolia
Bigel.)

FLORA OF THE DISTRICT OF COLUMBIA. 267

9. HIERACIUM L.

Leaves acute or acuminate, glabrous, glaucous beneath; heads small, 12-20-flowered,
on long slender stalks, loosely panicled.......---++------+++>- 1. H. paniculatum.
Leaves obtuse or rounded at the apex, copiously hairy; heads larger, the flowers
usually 20-50.
Stems hairy throughout, bearing numerous leaves, without a basal tuft of leaves at
flowering time; heads in narrow panicles or corymbs.
Inflorescence leafy-bracted, the heads on very stout stalks, 40-50-flowered.
2. H. scabrum.
Inflorescence not leafy-bracted, the heads on comparatively slender stalks, 15-20-
flowered ......--cccee cece cee cece e tee e eee ee eeee esses erres 3. H. gronovii.
Stems glabrous except sometimes at the base, bearing only one or two leaves, with
a rosette of basal leaves at flowering time, these usually veined or mottled with
purple; heads in open panicles, on very slender stalks........- 4, H. venosum.

1. Hieracium paniculatum L.
Woods about Washington. Aug.-Oct. Eastern N. Amer.

2. Hieracium scabrum Michx.
Dry woods; common. Aug.—Oct. Eastern N. Amer.

RoucH HAWKWEED.

8. Hieracium gronovii L. HAIRY HAWKWEED.
Dry woods and open fields; common. Aug.—Oct. Eastern U.S.

4. Hieracium venosum L. RATTLESNAKE-WEED.
Dry woods; abundant. Apr.-Sept. Eastern U. 8S. (Including H. venosum sub-

caulescens of Ward’s Flora.)

Crepis pulchra L. was found in waste ground near the Washington Monument in 1898
and 1899. Native of Eur. C. capillaris (L.) Wallr. (C. virens L.), also a European
species, was collected in the Department of Agriculture grounds as early as 1872 and
as late as 1894, but is not established in our region.

152, AMBROSIACEAE. Ragweed Family.

Fruit covered with very numerous long, usually hooked spines; leaves alternate.
1, XANTHIUM.

Fruit bearing usually 4-8 short tubercles; leaves all or only the lower ones opposite.
2. AMBROSIA.

1. XANTHIUM L. CocKLEBUR.

Stems armed in the axils with branched spines; leaves lanceolate, white beneath;
fruit with one short beak or beakless......--s+eceeeeeeeeeeeeee-ed. X. spinosum.
Stems without spines; leaves broadly ovate or broader, green on both sides; fruit

with 2 long beaks at the apex.
Body and prickles of the fruit glabrous or puberulent, the beaks straight or nearly so.
2, X. americanum.

Body and prickles of the fruit hairy, the beaks incurved.........-38. X. commune.
1. Xanthium spinosum L. SPINY COCKLEBUR.

Occasional in waste ground about Washington and Alexandria. Aug.—Oct.’ Native
of Eurasia; adventive in N. Amer.

2, Xanthium americanum Mill.

Waste or cultivated ground or alluvial flats. Aug.—Oct. Eastern N. Amer. (X.
canadense of Gray’s Manual; X. glabratum Britton.)
3. Xanthium commune Britton.

Alluvial soil along the Potomac and its larger tributaries. Aug.-Oct. Widely dis-
tributed in N. Amer.

268 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

2. AMBROSIA L.

Leaves opposite and alternate, once or twice lobed; receptacle chaffy; plants usually
low, seldom over 1 meter high................0.00.0.0-0eececee cece. 1. A. elatior.
Leaves all, except the uppermost among the inflorescence, opposite, palmately 3 or
5-lobed, or often undivided; receptacle not chaffy; plants usually 1.5-2 meters

high.
Leaves mostly 3-5-lobed.... 2.2.2.0... 0002 c cece cece ee eee eeeeee 2. A. trifida.
Leaves not lobed..... 2.222.200.2002 02 cece eee cece cece 2a. A. trifida integrifolia.
1. Ambrosia elatior L. COMMON RAGWEED,

Waste and cultivated ground and roadsides; abundant. Aug.-Oct. Nearly
throughout the U.S. (A. artemisiaefolia L.)
The abundant pollen of this plant is one of the chief causes of hay fever.

2. Ambrosia trifida L. GREAT RAGWEED,
Damp soil near streams; abundant. Aug.-Sept. Eastern N. Amer.
Known also as horseweed.

2a, Ambrosia trifida integrifolia (Muhl.) Torr. & Gray.
With the typical form.

153. ASTERACEAE. Aster Family.

In this family, as well as in the Ambrosiaceae and Cichoriaceae (all three of which
are often united as the Compositae), the form of the inflorescence is conspicuously
different from that of our other flowering plants, so much so as often to deceive ama-
teurs, who mistake the head of flowers for a single flower. The flowers are borne in a
close head (except in the pistilldte inflorescence of Ambrosiaceae) upon a flat or
convex receptacle, the latter often bearing chaff among the flowers. The head is
surrounded by an involucre of bracts. The corolla is tubular or strap-shaped. In the
Cichoriaceae all the flowers are strap-shaped. In the Asteraceae all the flowers may
be tubular, but more frequently the outer ones, or rays, are strap-shaped, while the
inner (forming the disk) are tubular. The fruit is an acheme. The calyx tube is
united with the fruit, while the calyx limb is represented by bristles, awns, scales,
etc., called the pappus.

A. Outer flowers of the heads never with strap-shaped (ray) corollas, the corollas with
5 equal or nearly equal lobes, or the corollas of the outer flowers sometimes larger
than those of the inner ones.

Leaves opposite or whorled.
Fruit covered with numerous slender hooked spines. (Ray flowers are present
in this genus but they are so small as to be overlooked easily.)

23. ACANTHOSPERMUM.
Fruit never with hooked spines.

Flowers yellow or yellowish; involucre of 2 distinct series of bracts, the outer
ones green, the inner brownish or straw-colored. Leaves often lobed or
composed of several leaflets.

Plants with viscid pubescence; pappus none..... ee eeeeee 22. POLYMNIA.

. Plants never with viscid pubescence; pappus of 2-6 long slender barbed

8 OS Bc 34. BIDENS.
Flowers white, purplish, or blue; bracts all alike or similar.

Stems climbing; bracts 4............... eee eee cece eee eee 4. MIKANIA.

Stems erect; bracts more than 4.............. weeeeeeeeee 3. EUPATORIUM.

Leaves alternate.
B. Leaves with spiny teeth, or the bracts armed with hooked spines, or deeply
toothed. Plants usually with more or less woolly pubescence.
Bracts ending in hooked spines. Leaves mostly borne at the base of the stem,
very large, not spine-toothed.......................0-0.. 47. ARCTIUM.

FLORA OF THE DISTRICT OF COLUMBIA. 269

Bracts ending in straight spines or sometimes not spiny.

Flower heads small, the body of the involucre less than 1 cm. thick, the
bracts merely toothed or else ending in very stout spines longer than the
involucre; plants usually low annuals; scar of insertion of the fruit on
the side just above the base......--...--. cece eee eee 50. CENTAUREA.

Flower heads usually large, the body of the involucre commonly 2-5 cm.
thick or, if small, the bracts ending in short slender spines; plants
usually very large and stout, biennials or perennials; scar of insertion of
the fruit basal.

Pappus bristles feather-like (plumose); receptacle bearing numerous

bristles............------------ ween e cece eee eee eeeee 48. CIRSIUM.
Pappus bristles smooth or nearly so, not plumose; receptacle without
bristles..... 22.22... eee eee ee eee eee ee eee eee 49. ONOPORDON.

BB. Leaves never with spiny teeth, the bracts not armed with spines, not toothed.

Leaves, at least the lower ones, lobed nearly or quite to the midrib; flowers

bright yellow or greenish yellow, the heads small. Plants usually strong-
scented.

Blades of the upper leaves oblong or ovate, merely shallow-toothed or with a
few deep lobes at the base. Flower heads in a usually flat-topped
corymb; pappus a short crown........------ 39. CHRYSANTHEMUM.

Blades of all the leaves divided into narrow lobes.

Flower heads in a flat-topped corymb, the flowers bright yellow; pappus a

short CrOWN.......-------- eee eee eee eects 40. TANACETUM.
Flower heads in long narrow racemes or panicles, the flowers greenish
yellow; pappus none.......-.---------+-eeeeeee eee 41. ARTEMISIA.

Leaves entire to coarsely toothed, never lobed nearly to the midrib; flowers
white, blue, or purple, or sometimes only whitish, never conspicuously
yellow.

Leaves with copious white woolly pubescence. Plants herbaceous; flowers
white, in small heads.

Leaves mostly basal, broad and spatulate, those of the stems small and
narrow; plants perennial, with long prostrate stolons, often forming
mats, the flowering stems simple below, bearing 1 or more heads at or
near the summit.........--.--------------+++++- 20. ANTENNARIA.

Leaves all borne on the stems, linear or very narrow; plants never with
stolons; much branched annuals or winter annuals, never forming mats.

Receptacle of the flower head bearing chafflike scales; leaves crowded,
usually erect or appressed to the stems, linear.......- 18. GIFOLA.
Receptacle of the flower head without scales; leaves usually not crowded,
spreading or ascending, linear to narrowly spatulate.
21. GNAPHALIUM.
Leaves never with white woolly pubescence.

Plants shrubby. Leaves coarsely toothed, glabrous; flowers white; pappus
of the fertile heads of very long bristles...........- 17. BACCHARIS.

Plants herbaceous.

Flower heads collected in dense heads surrounded by leaflike bracts.
Plants hairy, with numerous large basal leaves, the flowers bluish,

9-5 in each head.........---------++------ 2. ELEPHANTOPUS.
Flower heads in racemes, spikes, corymbs, or panicles, never in dense
heads.

Flower heads in long racemes or spikes; stems simple. Flowers rose-
purple, very showy; perennials, more or less pubescent, with nar-
row entire rigid leaves.....-.------++--0-+++---- 6. LACINARIA.

Flower heads in corymbs or panicles; stems usually conspicuously
branched,

270 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Flowers purple or deep purplish. Plants more or less pubescent.
Leaves with numerous small glands beneath; pappus white, in

one series, soft....................-.------- 19. PLUCHEA.
Leaves without conspicuous glands beneath; pappus purplish or
yellowish, in 2 series, stiff................... 1. VERNONIA.

Flowers white, whitish, or pale pink.
' Bracts finely’ pubescent; pappus bristles plumose, brownish;
leaves finely gland-dotted beneath............. 5. KUHNIA.
Bracts glabrous; pappus bristles smooth or nearly so, white;
leaves not gland-dotted beneath.

Bracts usually 5 (some small ones usually present also at the
base of the involucre); flowers usually 5 in each head; leaves
often pale beneath, usually as broad as long.

44, MESADENIA.

Bracts 12 or more; flowers 20 or more in each head; leaves green
on both sides, longer than broad.

Leaves with 2 very acute lobes at the base; bracts about 1 cm.

long; plants perennial............... .---45. SYNOSMA.
Leaves tapering at the base; bracts about 1.5 cm. long; plants
annual...... 22... eee eee eee 43. ERECHTITES.

AA. Outer flowers ofthe heads produced into a strap-shaped ray (the ray sometimes
small), the corollas of the inner flowers with 5 equal lobes.
C. Leaves opposite or whorled, or the uppermost sometimes alternate.
Stems winged. Rays yellow; leaves ovate, toothed.........-. 32. VERBESINA.
Stems not winged.
Rays pure white or purplish, small. Flower heads small; plants annual.
Leaves petioled, broadly ovate; pubescence of the stems spreading; achenes
pubescent...... 2.2... 2 2. eee eee 35. GALINSOGA.
Leaves sessile, narrowly lanceolate; pubescence of the stems appressed;
achenes pubescent on the flat apex but glabrous elsewhere.
28. ECLIPTA.
Rays yellow, sometimes pale but never white.
Bracts in 2 distinct series, the inner ones usually thin, brownish or yellowish,
the outer ones green, often leaflike.

Plants with a tuft of basal leaves dt flowering time; petioles usually longer
than the blades; bracts 10, 5 in each series; plants densely soft-hairy,
perennial... 22.22.2222. ...22 0222 25. CHRYSOGONUM.

Plants without a tuft of basal leaves at flowering time; petioles shorter
than the blades or often wanting; bracts more than 10; plants never
densely soft-hairy.

Pappus none or of 2 very short teeth; leaves each composed of 3 entire
leaflets or else divided into numerous linear segments; glabrous
perennials ...............0.......0.00020 eee eee 33. COREOPSIS.

Pappus of 2-6 barbed awns; leaves simple or pinnate, the blades or the
leaflets toothed, never linear; annuals or biennials, often pubescent.

34. BIDENS.
Bracts not in 2 distinct series, all alike or the outer ones gradually smaller.

Fruit covered with hooked spines. Annual with prostrate stems; leaves
petioled, toothed; rays very small....... 23. ACANTHOSPERMUM.

Fruit never with hooked spines.

Leaves (except sometimes the uppermost) deeply lobed; plants tall
and coarse, with viscid pubescence. Fruit glabrous, without
pappus; rays large or very small............ .....22. POLYMNIA.

FLORA OF THE DISTRICT OF COLUMBIA. 271

Leave shallowly toothed or entire; plants never with viscid pubescence.
Bracts all of equal length, in one series; pappus of numerous long
soft bristles. Leaves mostly borne at the base of the stem, the
stems bearing one or 2 pairs of sessile opposite leaves and a few
reduced alternate ones about the inflorescence. ..-. 42. ARNICA.
Bracts unequal, the outer ones shorter, in more than one series; pappus

never of long bristles.
Leaves mostly in whorls of 3 or 4; inner flowers of the head sterile,

not producing fruit. Tall perennials with glabrous stems.
24. SILPHIUM.
Leaves opposite by 2’s, never whorled; all the flowers fertile and
producing fruit.
Bracts obtuse or rounded at the apex; rays papery and persisting
on the fruit; perennials with petioled leaves.
27. HELIOPSIS.
Bracts acute or long-pointed; rays thin and usually soon falling
from the fruit; perennials or annuals..... 30. HELIANTHUS.
CC. Leaves alternate.
Stems narrowly or broadly winged.
Leaves with numerous oil glands; rays much broadened near the apex, deeply
3-lobed; fruit neither flattened nor winged, the pappus of 5-8 scales.
36, HELENIUM.
Leaves without oil glands; rays narrowed at the apex, shallowly toothed or
entire; fruit flattened, broadly winged, the pappus of 2 slender awns.

31. RIDAN.
Stems not winged.

D. Rays yellow, the inner flowers of the head yellow, brown, or purple.
Teeth of the leaves ending in short stiff spinelike hairs; bracts very viscid.
7. GRINDELIA.
Teeth of the leaves never ending in spinelike hairs, the leaves often entire;
bracts very slightly if at all viscid.
Leaves, at least some of them, deeply lobed or divided.
Bracts equal, in one series, a few very small ones sometimes present at
the base of the involucre; pappus of numerous soft white bristles.
46. SENECIO.
Bracts very unequal, the outer gradually shorter; pappus none or a
minute CrOWN..........0--- eee eee eee eee eee eee 29. RUDBECKIA.
Leaves entire or toothed, never lobed or divided.
Pappus of a few teeth or short awns or wanting; flower heads large, with
very large and showy rays.

Bracts reflexed; receptacles of the flower heads conical, 1-1.5 cm.
broad; disk flowers dark purple; leaves broader than linear.

29. RUDBECKIA.

Bracts erect or appressed; receptacles of the flower heads flat or some-
what convex, often 5 cm. broad or even larger; disk flowers often
yellow; leaves linear to broadly ovate-cordate.

380. HELIANTHUS.
Pappus of numerous slender bristles; flower heads large or often very
small.

Pappus in 2 series, the inner of long soft brownish bristles, the outer of
very short stiff bristles; heads about 1 cm. high, the rays nearly
or quite 1 cm. long; pubescence of the leaves of very long silky
appressed hairs, often deciduous............--- 8. CHRYSOPSIS.

272 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Pappus of a single series of long soft bristles; heads usually less than
7mm. high, the rays much less than 1 cm. long; pubescence of the
leaves never of long appressed silky hairs.

Leaves all linear or nearly so, entire; flower heads in a flat-topped
corymb; receptacle of the flower head hairy or bristly; ray
flowers more numerous than the disk flowers. .10. EUTHAMIA.

Leaves, at least some of the lower ones, broader than linear, usually
toothed; flower heads usually in a long narrow panicle or in a py-
ramidal panicle or in clusters in the axils of the leaves; receptacle
of the flower head usually pitted and not hairy or bristly; ray
flowers usually not more numerous than the disk flowers.

9. SOLIDAGO.
DD. Rays never yellow, usually white or purple.

Leaves, at least most of them, divided nearly or quite to the midrib into
numerous lobes. Rays usually white; plants often strong-scented.

Heads very small, very numerous, on short stalks in dense corymbs, the
involucres about 3 mm. wide, the rays about 2 mm. long; perennials

with basal tufts of soft, much divided, plumelike leaves.
. 37. ACHILLEA.
Heads larger, usually solitary on long stalks, the involucres 6-15 mm. broad,
the rays mostly 14-20 mm. long; annuals or perennials, never with

basal tufts of soft plumelike leaves.

Receptacles of the flower heads bearing numerous chafflike scales;
plants annual or sometimes biennial, without basal tufts of leaves at
time of flowering............ 2-20 ee eee eee ee ee ees 38. ANTHEMIS.

Receptacles of the flower heads naked, without scales; plants perennial,
usually with basal tufts of leaves at time of flowering.

39. CHRYSANTHEMUM.
Leaves entire or toothed, never lobed.

Pappus of 2 or 3 very inconspicuous scales. Flower heads about 5 mm.
broad, in a flat-topped corymb; rays white, very small; leaves broad,
harsh to the touch, with short rough pubescence.26. PARTHENIUM.

Pappus of numerous long slender bristles.

Rays small, equaling or usually shorter than the diameter of the involucre,
not exceeding 3 mm. in length, white or tinged with pink.

Plants annual; leaves linear or nearly so; bracts linear, very acute.

16. LEPTILON.

Plants perennial; leaves lance-oblong to obovate; bracts broader than

linear, obtuse.....-.-..2 2-2-0 e ee eee eee ee eee cece 9. SOLIDAGO.
Rays large and showy, longer than the diameter of the involucre, usually
much more than 3 mm. long.

Bracts nearly equal in length, in one or 2 series, narrowly linear, very
numerous. Rays white, pink, or purplish; pappus bristles equal,
in One SerieS...-...---- 22. eee ee eee eee ee eee 15. ERIGERON.

Bracts very unequal, the outer shorter, in several series, either broad
or, if very narrow, evidently broadest at the base.

Pappus bristles in 2 series, the outer ones shorter than the inner.
Rays white; leaves broader than linear...18. DOELLINGERIA.
Rays violet; leaves linear............-.--..----. 14. IONACTIS.

Pappus bristles in one series, equal or somewhat unequal.

Rays 4 or 5, white; involucres much longer than thick. Bracts
broad, obtuse, cartilaginous......... 11. SERICOCARPUS.

Rays numerous; involucres usually nearly as broad as long.
12. ASTER.

FLORA OF THE DISTRICT OF COLUMBIA. 273

1. VERNONIA Schreb. IRon-WEED.

Pappus purplish; bracts with long slender tips; leaves elongate-lanceolate or narrowly

lance-oblong, gradually narrowed at the base..........-- 1. V. noveboracensis.
Pappus yellowish; bracts with short stout tips; leaves ovate-lanceolate, usually ab-
ruptly narrowed at the base........... 22.2. - 2 eee eee eee eee eee eee 2. V. glauca.

1. Vernonia noveboracensis (L.) Willd.
Woods and open fields. Aug.-Sept. Eastern U. 8.

2. Vernonia glauca (L.) Britton.
Woods and open fields. July-Oct. Eastern U. 8.

2. ELEPHANTOPUS L.

1. Elephantopus carolinianus Willd. ELEPHANT’S-FOOT.
Dry or moist woods; common. Aug.-Oct. Eastern U. 8S.
Flowers pale purplish, in small, narrow, crowded heads.

3. EUPATORIUM L.

Besides the species listed below, two others have been found here asimmigrants, but
are probably not established: Z. capillifolium (Lam.) Small, with leaves dissected into
filiform lobes, native farther south, was collected near Chain Bridge, Va., Oct. 18,
1912 (Albert Ruth); E. cannabinum L., native of Europe, with 3-lobed leaves, was
found along Hunting Creek, Sept. 4, 1899 (Steele; a single plant).

Flowers pink or purplish; leaves all or mostly in whorls of 3-7, petioled. Plants tall
and coarse; bracts imbricate in several rows.......-.---------- 1. E. purpureum.
Flowers white, or in one species blue or violet; leaves mostly opposite, sometimes in
whorls of 3 or 4, but then usually sessile, the uppermost leaves sometimes alternate.
Leaves conspicuously petioled.
Flowers blue or violet; bracts with violet tips.......---..-- 14. E. coelestinum.
Flowers white; bracts with greenish or whitish tips.
Leaves with minute resin dots, the uppermost leaves alternate; involucre with
several small bracts at the base, the large bracts mostly truncate at the
7) 0), cca 8. E. serotinum.
Leaves without resin dots, all opposite; involucre with few or no small bracts
at the base, the long bracts obtuse or acute.
Leaves thin, the blades mostly 3.5-8 cm. wide, the tips long-tapering, the
teeth acute; petioles mostly 2.5-5 cm. long........ 12. E. urticaefolium.
Leaves thickish, the blades mostly 3-5 cm. wide, acute to very obtuse, not
long-tapering, the teeth usually very obtuse; petioles mostly 0.5-1.5 cm.

long ...-. 2... eee eee eee ee eee re eee eee eee ne eens 13. E. aromaticum.
Leaves sessile or nearly so.
Leaves perfoliate (the bases united around the stem) ....---- 2. E. perfoliatum.

Leaves not perfoliate, the bases distinct.
Leaves narrowed and acute at the base, or in one species the base often obtuse,
but the blades then broadest at or near the middle.
Bracts all or mostly very acute, with conspicuous white scarious tips; larger
leaves often 2.5-3.5 cm. wide.......----- +--+ eee eee eee eee 4. E. album.
Bracts obtuse or rounded at the apex, not whitish or with a very narrow
scarious border; leaves all or mostly less than 2 cm. wide.
Leaves linear, mostly 1.5-5 mm. wide, entire or the larger ones serrate,
many of them in whorls of 3 or 4.......-.------- 9. E. hyssopifolium.
Leaves lance-linear to lanceolate, mostly 7-20 mm. wide, all or most of
them serrate.

69289—19——18

274 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Leaves lance-linear, many of them in whorls of 3, the larger ones 7-12 mm,
wide, the lateral nerves not very conspicuous..... 10. E. torreyanum.

Leaves lanceolate or narrowly lanceolate, opposite, the larger ones mostly
12-20 mm, wide, the lateral nerves very conspicuous.
11. E. altissimum.
Leaves obtuse to truncate at the base, the blades broadest at or near the base.

Leaves glabrous beneath, often 5 times as long as broad, very long-tapering

at the apex; bracts obtuse................-2-2.--0- 3. E. sessilifolium.

Leaves pubescent beneath, the blades less than 3 times as long as broad, the

larger ones never very long-tapering at the apex, usually obtuse or acute;
bracts acute or acutish.

Leaves mostly 2.5-3 times as long as broad, ovate, ovate-oblong, or lance-
oblong, with few coarse irregular teeth; leaves of the inflorescence
alternate.............. 222 e eee eee eee eee eee 5. E. verbenaefolium.

Leaves less than twice as long as broad, broadly ovate or rounded-ovate,
with numerous close even teeth, or the lower leaves sometimes irregu-
larly lobed; leaves of the inflorescence all or nearly all opposite.

Leaves broadly ovate, acute or acutish, the larger ones 6-9 cm. long,

usually rounded at the base.....................- 6. E. pubescens:

Leaves rounded-ovate, usually obtuse, the larger ones mostly 3-5 cm.
long but sometimes longer, usually truncate at the base.

7. E. rotundifolium.

1. Eupatorium purpureum L. JOE PYE WEED.

Low wet ground or in moist woods or ravines; frequent. Aug.Sept. Eastern N.
Amer. (E£. trifoliatum L.)

A somewhat variable species, In shaded woodlands the plants have thinner,
sparsely pubescent leaves. The common form, of exposed situations, has thicker,
more pubescent leaves, but does not differ essentially from the woodland form, It is
E. purpureum maculatum (L.) Darl. (EZ. maculatum L.).

2. Eupatorium perfoliatum L. BONESET.
Low wet ground; common. Aug.-Sept. Eastern U.S.
The leaves are usually opposite, but sometimes in whorls of 3.

3. Eupatorium sessilifolium L. UPLAND BONESET,

Wooded hillsides; common. <Aug.—Sept. Eastern U.S.

In specimens collected near Takoma Park by Steele the leaves are very shortly
petiolate, and obtuse, rather than rounded, at the base.

Ward reported a hybrid between this species and E. pubescens. This form, which
is represented by séveral specimens, has pubescent leaves intermediate in shape
between those of the two species, In the key it is likely to fall under E. verbenae-
folium, from which it is distinguished by the thinner, closely and evenly serrate
leaves.

4. Eupatorium album L.

Dry fields; common, especially on the Coastal Plain. July-Sept. Eastern U. S&.,
northward to Long Isl.

5. Eupatorium verbenaefolium Michx.

Low ground, often in sphagnum bogs, or in dryish fields; Coastal Plain. Aug.-Sept.
Eastern U.S. (£. teucrifolium Willd.)

6. Eupatorium pubescens Muhl.

Woods; chiefly along the upper Potomac, but also on the Coastal Plain. Aug.—Sept.
Eastern U. 8.

Closely related to E. rotundifolium; some specimens can be placed almost equally
well in either species. The lowest leaves are often deeply lobed in both species.

FLORA OF THE DISTRICT OF COLUMBIA. 275

7. Eupatorium rotundifolium L.
Open low ground or in’ woods; Coastal Plain. July-Sept. Eastern U. 8.
8. Eupatorium serotinum Michx.
Found only at Hickeys Hill, Eastern Branch, Sepi., 1899 (Steele). Eastern U. 8.
9. Eupatorium hyssopifolium L.
Sandy fields; common, especially on the Coastal Plain. Aug.-Sept. Eastern U.S.
10. Eupatorium torreyanum Short.
Dry fields; frequent. Aug.—Sept. Pa. and southward. (E. hyssopifolium of.
Ward’s Flora, in part.)
11. Eupatorium altissimum L.
Dry soil; Piedmont Region. Aug.-Sept. Eastern U.S.
12. Eupatorium urticaefolium Reich. WHITE SNAKEROOT.
Deciduous woods; common. Aug.-Sept. Eastern N. Amer. (Z£. ageratoides L. f.)
13. Eupatorium aromaticum L.
Woods; common. Sept. Eastern U. 8.
One specimen from our region has leaves in whorls of 3.
14. Eupatorium coelestinum L. MIST-FLOWER.
Low woods or fields; common. July-Oct. Eastern U.S., north to N. J. (Cono-
clinium coelestinum DC.)

4, MIKANIA Willd.

1. Mikania scandens (L.) Willd. CLIMBING HEMPWEED.
Swamps or wet ground. Aug.-Sept. Eastern N. Amer. to tropical S. Amer.
(Willughbaea scandens Kuntze.)
Readily distinguished from all our other Asteraceae by its climbing stems; flowers
flesh-colored.

5. KUHNIA L.
1. Kuhnia eupatorioides L. FALSE BONESET.

Woods. Sept.-Oct. Eastern U.S.
6. LACINARIA Hill. Burazine star.

Bracts very acute, stiff, with thick firm margins...........-..-.-.-- 1. L. squarrosa.
Bracts obtuse or rounded at the apex, with thin scarious margins.
Heads 1 cm. broad or narrower, often numerous; bracts erect and appressed; leaves

linear 7 mm. wide or less...... eee c ee ee cece ee cece eeee 2. L. graminifolia.
Heads 1.5-2 cm. broad, few; outer bracts reflexed; leaves lance-oblong, mostly
1.54 em. wide... 20.2... ce eee eee eee ences 8. L. scariosa.

1. Lacinaria squarrosa (L.) Hill.

Dry fields near Alexandria, Accotink, and Cropley. July-Aug. Pa. and south-
ward. (Liatris squarrosa Willd.)
2. Lacinaria graminifolia (Walt.) Kuntze.

Dry fields and open woods of the Coastal Plain; common. Sept.-Oct. South-
eastern U. S., north to Md. (Liatris graminifolia Pursh.)
8. Lacinaria scariosa (L.) Hill.

Hillsides and bluffs of the Piedmont Region, Virginia side of the Potomac. Sept.-
Oct. Eastern U.S. (Liatris scariosa Willd.)

7. GRINDELIA Willd.

1. Grindelia squarrosa (Pursh) Dunal. GUM-PLANT.
Near the mouth of Hunting Creek, August, 1916 (Miss F. W. Layton). Native of
the western U. 8.
Characterized by the very ‘‘gummy” heads of yellow flowers.

276 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

8. CHRYSOPSIS Ell.

1, Chrysopsis mariana (L..) Ell. . GOLDEN ASTER.
Fields or open woods; common, Aug.-Oct. Eastern U. 8. '
A specimen of Chrysopsis gossypina (Michx.) Ell. was collected along the railroad
at Silver Springs, Sept. 1904 (J. H. Painter), This species ranges from Va. to Fla.,
and is doubtless adventive here.

9, SOLIDAGO L. GoLpDENROD.

Heads in small clusters in the axils of the leaves, the leaves much longer than the
clusters; stems glabrous.
Leaves rounded-ovate, ovate, or broadly elliptic, abruptly narrowed at the base
into a winged petiole; teeth of the leaves long, spreading; stem angled.
1. S. flexicaulis.
Leaves lanceolate or narrowly oblong-lanceolate, sessile, the teeth low, appressed ;
stem round...... a 2. S. caesia.
Heads all or mostly in broad or narrow panicles, in one species in corymbs, clusters
of heads sometimes present also in the axils of some of the leaves; stems glabrous
or pubescent.
Leaves all entire, anise-scented . . 2.2.2.2... 0.00.00. ee eee eee 8. S. suaveolens.
Leaves all or at least the larger ones with large or small teeth, not anise-scented.
Stems glabrous up to the inflorescence, the branches of the panicle often pubes-
cent.
Leaves very hairy beneath with long or short hairs, often very rough on the
upper surface. Heads in long slender one-sided racemes.
Leaves 3-nerved, 2 of the lateral nerves much stronger than the others.
16a. S. serotina gigantea.
Leaves pinnately nerved, the lateral nerves all alike or nearly so.
10. S. ulmifolia.
Leaves glabrous beneath, or rarely with a few scattered hairs along the princi-
pal nerves, smooth on the upper surface.
Margins of the leaves smooth; plants growing on rocks. Heads large, 7-8
mm. long, in very narrow panicles..................--- 7. S. racemosa.
Margins of the leaves rough with very short thick hairs; plants growing in
soil.
Heads large, 5.5-8 mm. long (from base of involucre to top of disk), not in
one-sided racemes; lower leaves mostly obtuse..........-- 5. S. erecta.
Heads smaller, usually decidedly less than 5.5 mm. long, but sometimes
6 mm. long, arranged in one-sided racemes; leaves all very acute.
Leaves linear-lanceolate, the largest ones 1.3 cm. wide and most of them
narrower, 3-nerved; heads about 3.5 mm. high.....14. S. rupestris.
Leaves lanceolate or broader, most of them over 1.5 cm. wide, usually
2-4 cm. wide.
Leaves 3-nerved (that is, 2 of the lateral nerves much stronger than
the others). Heads 3.5-4 mm. high............... 16. S. serotina.
Leaves pinnately nerved, the lateral nerves all alike.
Leaves all sessile, mostly ovate or elliptic and less than 3 times as

long as broad, rarely longer; plants with stolons.
11. S. elliottii.

Leaves, at least the lowest ones, narrowed to winged petioles, usually
lanceolate and 4 times as long as broad or often much longer;
plants without stolons.

Heads 5-5.5 mm. high, the branches of the panicle short (usually
5 cm. or less) and stout; petioles of the lower leaves sheathing
the stem..........- 2.2 ee ee eee cee eee eee 12. S. neglecta.

FLORA OF THE DISTRICT OF COLUMBIA. 277

Heads 44.5 mm. high, the branches of the panicle long, slender,
recurved; petioles not sheathing.........------ 13. S. juncea.
Stems pubescent throughout (rarely glabrous at the base) with fine and close or
long and spreading hairs.
Leaves 3-nerved (that is, 2 of the lateral nerves very conspicuous), lanceolate
or narrowly lanceolate. Heads in slender one-sided racemes.
Heads 3-3.5 mm. high; leaves usually smooth on the upper surface; branches

of the panicle slender..........------+-+++++++++--+- 15. S. canadensis.
Heads 44.5 mm. high; leaves very rough on the upper surface; branches of
the panicle rather stiff and stout......-------+-+-+-++- 17. S. altissima.

Leaves pinnately nerved, none of the lateral nerves much more conspicuous
than the others.
Rays white. Heads 5-6 mm. long, the branches of the panicle not one-sided,
3. S. bicolor.
Rays yellow.

Heads 7-10 mm. high; bracts pubescent on the back, conspicuously
nerved; led¥es very rough, stiff, densely pubescent, the upper ones
obtuse......... ee eee ee eee eee teen eee nents ....19. S. rigida.

Heads 6 mm. high or less; bracts glabrous on the back, not nerved; leaves
thin, the upper ones acute.

Leaves pubescent with very minute, close hairs.
Bracts oblong or narrowly oblong, obtuse; heads in one-sided racemes;

achenes glabrous......-..--+--------2eeeee rr eeee 6. S. puberula.
Bracts linear or narrowly linear, acutish; racemes not one-sided ;
achenes pubescent....-...--.--------+++2e+ee- 18. S. nemoralis.

Leaves with long slender spreading hairs on the lower surface.
Heads not in one-sided racemes; leaves not rugose, the lower stem
leaves narrowed into winged petioles; plants without stolons.

4. S. hispida.
Heads in one-sided racemes; leaves more or less rugose, the stem leaves
sessile; plants with stolons......---...-+--+---++++++- 9. S. rugosa.

1. Solidago flexicaulis L.
Shaded bluffs along the upper Potomac. Sept.-Oct. Eastern N. Amer. (8.
latifolia L.)
2. Solidago caesia L.
Moist or dry woods; common. Sept.Oct. Eastern N. Amer.
8. Solidago bicolor L. SILVER-ROD.
Dry or moist woods; common. Sept.—Oct. Eastern N. Amer.
Readily distinguished from our other species by the white rays.
4. Solidago hispida Muhl.
Dry ground; Rock Creek Park; Pinehurst; rare. Sept.-Oct. Eastern N. Amer.
(S. bicolor concolor Torr. & Gray.)
5. Solidago erecta Pursh.
Wooded ground; common. Sept.-Oct. Eastern U.S8., northtoN. Y. (8S. speciosa
angustata Torr. & Gray.)
Rays turning white in age.
6. Solidago puberula Nutt.
Open woods; Lanham and Laurel. Sept.-Oct. Eastern N. Amer.
7%. Solidago racemosa Greene.
On rocks along the upper Potomac. Aug.—Oct. Newf. to Va. (S. virga-aurea
humilis A. Gray.)
Usually low and stout, but sometimes a meter high.

278 ° CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

8. Solidago suaveolens Schoepi. SWEET-SCENTED GOLDENROD.
Sandy woods of the Coastal Plain, July-Sept. Eastern N. Amer. (S. odora Ait.)
9. Solidago rugosa Mill.
Dry or moist ground; common. Sept.-Oct. Eastern N, Amer. (8. altissima of
Ward’s Flora.)
S. rugosa aspera (Ait.) Fernald (8. aspera Ait.) is a form with thick rugose leaves,
these often rounded at the base (rather than narrowed, as in the species).
10. Solidago ulmifolia Muhl.
Woods; chiefly in the Piedmont Region. Aug.-Sept. Eastern N. Amer,
11. Solidago elliottii Torr. & Gray.
Sphagnum bogs of the Coastal Plain. Aug.-Oct. Eastern U. S., near the coast.
12. Solidago neglecta Torr. & Gray. SWAMP GOLDENROD.
Sphagnum bogs of the Coastal Plain. Sept.-Oct. Me. to Md. and westward. (S.
stricta of Ward’s Flora. )
18. Solidago juncea Ait. EARLY GOLDENROD.
Chiefly in old fields; common, July-Sept. Eastern N. Amer. (S. arguta of
Ward’s Flora.)
14. Solidago rupestris Raf.
Along the upper Potomac. Aug.-Sept. Eastern U. S.
15. Solidago canadensis L.
Low ground along the upper Potomac. Aug.-Oct. Eastern N, Amer.
16. Solidago serotina Ait.
Low ground, among rank weeds; frequent. Aug.—Oct. Widely distributed in N.
Amer. (8S. gigantea of Ward’s Flora.)
16a. Solidago serotina gigantea (Ait.) A. Gray.
With the typical form; common. July-Aug. Eastern U. S.
17. Solidago altissima Ait. TALL GOLDENROD.
Roadsides and borders of fields; common. Aug.—Oct. Eastern U. 8. (S. cana-
densis of Ward’s Flora. )
18. Solidago nemoralis Ait.
Dry fields; common. Sept.-Oct. Eastern N. Amer.
19, Solidago rigida L.
Dry fields; Woodley Park and Cabin John; rare. Sept. Eastern U. 8., west to
Colo. (Oligoneuron rigidum Small.)

10. EUTHAMIA Nutt.

1. Euthamia graminifolia (L.) Nutt.
Woods and open fields; common. Sept.-Oct. Eastern N. Amer. (Solidago grami-
nifolia Salisb.; S. lanceolata of Ward’s Flora.)

11. SERICOCARPUS Nees. WHITE-TOPPED ASTER.

Leaves entire, linear or linear-spatulate, glabrous or nearly so; involucres 4-7 mm.

long; pappus white............ wee eee eee e cece eee eee eee eee 1. 8. linifolius.
Leaves nearly all toothed, usually obovate, pubescent; involucres 5-9 mm. long;
pappus rusty....... 2... cece eee 2. S. asteroides.

1. Sericocarpus linifolius (L.) B. S. P.

Thin woods and open fields; chiefly north and east of Washington. June-Oct.
Eastern U.S. (S. solidagineus Nees.)
2. Sericocarpus asteroides (LL.) B.S. P.

Dry woods and open fields; common. June-Sept. Eastern U. 8. (S. conyzoides
Nees. )

FLORA OF THE DISTRICT OF COLUMBIA. 279

12. ASTER L.! AstTEr.

Leaves, at least the lowest ones, petioled, the petioles not winged, the blades more or
less cordate at the base (rarely only truncate), usually heart-shaped.
Stem leaves, at least most of them, with sessile clasping bases. Rays pale blue to
violet. 6. A. undulatus.
Stem leaves never with sessile clasping bases, usually petioled, sometimes sessile.
Leaves all entire, 3.5 cm. wide or less, the larger ones more than twice as long as
broad. Rays violet-blue.........- Seca e ese neers cesseaes 8. A. shortii.
Leaves, at least the lower ones, conspicuously toothed, the larger ones much
wider, less than twice as long as broad.
Heads panicled; rays usually pale blue. Bracts narrow, with conspicuous,
sharply defined, green tips.
Bracts obtuse; involucre about 5 mm. high.......--.---- 4. A. cordifolius.
Bracts very acute; involucre about 6 mm. high......... 5. A. sagittifolius.
Heads in flat-topped or round-topped corymbs; rays white or pink.

Leaves thin, mostly smooth, the teeth spreading, very acute.
1. A. divaricatus.

Leaves usually thick and firm, often rough on the upper surface; the teeth

low, rounded or very obtuse and abruptly short-pointed . .2. A. schreberi.
Leaves never both cordate at the base and petioled, sometimes cordate at the base
but then sessile.

Stem leaves with a clasping sessile base, or if not very conspicuously clasping at least
evidently broadened at the base, or the leaves sometimes with winged petioles
and these broadened and clasping at the base.

Stems hairy throughout.
Leaves, at least most of them, conspicuously toothed. Rays lilac-blue to white.
10. A. puniceus.
Leaves entire.

Heads comparatively small, the disk 8-12 mm. broad; leaves only slightly
clasping or merely broadened at the base. Bracts very viscid; rays
violet-purple....-.-... 2.222 e ee ee ee eee eee e cence 9. A. oblongifolius.

Heads large, the disk 12-16 mm. broad; leaves strongly clasping.

Stem rough with very short or minute hairs; leaves often narrowed just
above the base; involucre 6-7 mm. long, the bracts close, with slightly
spreading tips; rays mostly blue-purple ....-.-..------- 7. A. patens.

Stem hirsute with long hairs; leaves not narrowed above the base; in-
volucre 8-10 mm. long, the bracts loose and spreading; rays violet-
purple...........----2 eee eee ee eee eects 8. A. novae-angliae.

Stems glabrous below, sometimes hairy above.
Lower leaves abruptly contracted into long, narrowly winged petioles, the

blades mostly ovate, all of them sharply toothed. Rays violet. .

11. A. prenanthoides.

Lower leaves slightly if at all contracted, the petioles, if any, very broadly

winged, the blades oblong to linear, entire or remotely toothed, those of
the upper leaves always entire.

1 Some of the species of this genus are extremely variable and many of the forms
which are regarded by most botanists as mere variants have been described as spe-
cies. E. S. Burgess, for instance, in his “Species and. variations of Biotian Asters”
(Mem. Torrey Club 13. 1906), described about 80 new species of the group repre-
sented with us by A. divaricatus and A. schreberi, but only one of these is accepted
in the last edition of Gray’s Manual. Many of them were reported from our region,
but they appear to be distinguished by unstable characters. A conservative view
has been adopted in the present treatment, and the two species mentioned above
have been accepted in their usual sense.

280 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Leaves mostly lanceolate or oblong and 14 cm. wide; plants somewhat
glaucous. Rays blue-violet..................202- cece eee 12. A. laevis.
Leaves mostly linear or nearly so and less than 1 cm. wide; plants not glau-
cous. .
Bracts appressed, the tips acutish, the green portion very short; rays
a (0) C) 18. A. concinnus.
Bracts with spreading, usually very obtuse tips, the green portion extend-
ing nearly to the base in-the outer bracts; rays blue-violet to white.
14. A. novi-belgii.
Stem leaves with acute or obtuse bases, never clasping or broadened at the base.
Leaves silky-hairy, entire. Rays purple-violet................. 15. A. concolor.
Leaves never silky-hairy, entire or toothed.
Leaves very thick and rough, the basal ones with winged petioles; heads in
corymbs; disk of the head (from base of involucre to top of pappus) 11-14
mm. long. Rays pale violet...................2.2.200005 16. A. radula.
Leaves usually thin, never rough, without definite petioles; heads not in
corymbs; disk 10 mm. long or usually shorter.
Heads solitary at the ends of slender branches, these bearing very numerous
small linear bractlike leaves.
Bracts with rigid tips, the outer bracts very acute; leaves of the flowering
branchlets appressed or ascending; rays white or nearly so.
22. A. ericoides.
Bracts with soft thin tips, the outer bracts obtuse; leaves of the flowering
branchlets spreading; rays pale purple or blue....... 19. A. dumosus.
Heads in broad or narrow racemes or panicles, often clustered, never solitary
at the ends of long and densely leafy branches.
Heads large, the disk 7-9 mm. long; panicles broad, not one-sided. Leaves
mostly lanceolate and toothed; rays white or purplish.
20. A. paniculatus.
Heads small, the disk less than 6 mm. long; panicles or racemes long and
narrow, often one-sided.
Heads in narrow panicles, these not one-sided. Leaves linear-lanceo-
late, sharply toothed; rays white or purplish...... 21. A. tradescanti.
Heads in narrow one-sided racemes or panicles.
Leaves mostly lanceolate and conspicuously toothed; rays white or
bluish..... 20... 2.222 cece eee ee eee eee eee 17. A. lateriflorus.
Leaves linear or lance-linear, entire or nearly 80; rays white.
18. A. vimineus,

1. Aster divaricatus L. WHITE WOOD ASTER.

Moist woods or thickets; chiefly in the region of Rock Creek and the upper Potomac;
frequent. Aug.—Oct. Eastern N. Amer.

2. Aster schreberi Nees.

In ravines or moist woods or thickets, chiefly in the region of Rock Creek and the
upper Potomac. July-Oct. Eastern N. Amer. (A. corymbosus and A. macrophyllus
of Ward’s Flora.)

8. Aster shortii Hook.

Wooded banks and islands of the upper Potomac; rare. Sept.-Oct. Pa. to Wis.
and southward.

4. Aster cordifolius L. BLUE WOOD ASTER.

Low woods and thickets; along the Potomac from Georgetown westward; common,
Sept.-Oct. Eastern N. Amer.

FLORA OF THE DISTRICT OF COLUMBIA. 281

5. Aster sagittifolius Willd.

Woods along the Potomac from Georgetown westward. Sept.—Oct. Eastern N.
Amer.

6. Aster undulatus L.

Dry or moist woods, thickets, or hillsides; common. Sept.-Oct. Eastern N.
Amer.

A variable species of which numerous segregates have been proposed, based chiefly
on the form of leaves and inflorescence. It seems better, however, to treat these slight
variations as forms of one readily recognizable species.

7. Aster patens Ait.

Dry woods or thickets or open fields; common. Sept.-Oct. Eastern U. 8.

A, patens phlogifolius Nees (A. phlogifolius Muhl.) is a form with thinner, often
larger, less rough leaves than the species. It does not seem to differ essentially, at least
in our range, although it has often been recognized as a distinct species.

8. Aster novae-angliae L. New ENGLAND ASTER.

Moist thickets and fields along the upper Potomac; infrequent. Sept.-Oct. Widely
distributed in the U. S. and Can.

9. Aster oblongifolius Nutt.

On rocks and exposed slopes along the upper Potomac. Sept.-Oct. Pa. to Minn.
and southward.

10. Aster puniceus L. RED-STALKED ASTER.

Swamps and low ground; frequent. Sept.-Oct. Eastern N. Amer.

11. Aster prenanthoides Muhl.

Ravines or moist woods along the upper Potomac; Hunting Creek; infrequent.
Sept.-Oct. Eastern U. 8., south to Va.

12. Aster laevis L. SMOOTH ASTER.

In woods; northward and eastward; rare. Sept. Widely distributed in the U.S.
(A. laevis potomacensis Burgess.)

13. Aster concinnus Willd.

Woodley Park, in 1878 (Ward). Eastern U.S.

Our material perhaps not essentially different from the preceding species.
14. Aster novi-belgii L.

Swamps or low ground, eastward. Sept.—Oct. Eastern N. Amer. (A. aestivus of
Ward’s Flora.)

15. Aster concolor L. SILVER ASTER.

Dry soil, northeastward; also near Barcroft; infrequent. Sept.-Oct. Eastern
U.S.

16. Aster radula Ait.

Powdermill Bogs and near Suitland. Aug.Sept. Eastern N. Amer., south to
Md.

17. Aster lateriflorus (L.) Britton. CALICO ASTER.

Dry or moist fields and thickets; common. Sept.-Oct. Eastern N. Amer. (A.
diffusus Ait.; A. miser Nutt.; A. hirsuticaulis Lind].)

Variable in pubescence and form of inflorescence. The most copiously pubescent
form is A. lateriflorus hirsuticaulis (Lind1.) Porter.

18. Aster vimineus Lam.

Moist soil; frequent. Sept.Oct. Eastern N. Amer. (A. tradescanti of Ward’s

Flora, in part.)
19. Aster dumosus L.
Fields or open woods; northward and eastward. Aug.-Oct. Eastern N. Amer.

282 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

20. Aster paniculatus Lam.

Low ground; chiefly along the Potomac, but also northeastward. Aug.-Oct.
Eastern N. Amer. (A. simplex of Ward’s Flora.)
21. Aster tradescanti L.

Rock Creek region and perhaps elsewhere. Sept.-Oct. Eastern U. S., south to
Va.

Our form may not be essentially different from A. lateriflorus.
22. Aster ericoides L.

Dry or moist fields and hillsides; common. Sept.-Oct. Eastern N. Amer.

13. DOELLINGERIA Nees.

Achenes pubescent; involucres about 4 mm. long; leaves lanceolate or ovate.
1. D. umbellata.

Achenes glabrous; involucres 6-7 mm. long; lower leaves often obovate. .2. D. infirma.

1. Doellingeria umbellata (Mill.) Nees.
Dry or moist fields or woods; common. July-Oct. Eastern N. Amer. (Aster
umbellatus Mill.; Diplopappus umbellatus Hook.)

2. Doellingeria infirma (Michx.) Greene.
Dry or moist fields and woods; frequent. July-Oct. Eastern U.S. (Aster infirmus
Michx.; Diplopappus cornifolius Less. )

14. IONACTIS Greene.

1. Ionactis linariifolius (L.) Greene.

Dry or rocky woods; common. Sept.-Oct. Eastern U.S. (Aster linariifolius L.;
Diplopappus linariifolius Hook.)

A handsome plant, resembling an Aster, with showy violet rays; leaves linear and

rather stiff.
15. ERIGERON L.

Plants perennial; stem leaves sessile and usually clasping; rays commonly bluish
purple or pink.
Plants producing slender stolons; heads 12-18 mm. broad; rays about 50; leaves
densely long-hairy...... 2.2.00... 0002 e cece eee eee cee eee ee 1. E. pulchellus.
Plants without stolons; heads about 10 mm. broad; rays very numerous, 100 or more;
leaves nearly glabrous................c0 0c cece ee ee ee eee 2. E. philadelphicus.
Plants annual or biennial; stem leaves, at least the lower ones, petioled; rays very
numerous, usually white, sometimes pinkish.
Pubescence of the stems composed of few long soft spreading hairs; leaves coarsely
and sharply toothed, the lower ones ovate or oval.............. 3. E. annuus.
Pubescence of the stems composed of short appressed hairs; leaves entire or very
obscurely and remotely toothed, the lower ones oblanceolate. ..4. E. ramosus.

In the National Herbarium there is a specimen of Erigeron vernus (L.) Torr. & Gray
said to have been collected in the vicinity of Washington by Gerald McCarthy; prob.
ably it is wrongly labeled.

1, Erigeron pulchellus Michx. RoBIN’S PLANTAIN,
Woods and meadows; common. Apr.~May. Eastern U.S. (LE. bellidifolius Muhl.)-
A colony of flowering plants is shown in plate 41B.

2. Erigeron philadelphicus L. FLEABANE.
Fields and wet meadows along the Potomac; frequent. May-June. Nearly

throughout the U. S. and Can.

3. Erigeron annuus (L.) Pers. WHITE-TOP.
Fields; very abundant. June-Oct. Eastern N. Amer.

FLORA OF THE DISTRICT OF COLUMBIA. 283

4, Erigeron ramosus (Walt.) B.S. P. DAISY FLEABANE.
Fields; common. May-Oct. Widely distributed in the U. 8. and Can. (E.

strigosus Muhl.)
16. LEPTILON Raf.

1. Leptilon canadense (L.) Britton. HORSEWEED.
Waste and cultivated ground; very abundant. Aug.-Sept. A common weed in

cultivated and waste ground nearly throughout N. Amer. (£rigeron canadensis L.)
Flowers white, in very numerous small heads. The minute rays are likely to be

overlooked.
17. BACCHARIS L.

1. Baccharis halimifolia L. GROUNDSEL BUSH.
Collected at Little Falls, Accotink, near Cabin John, and at Bennings; rare. Along
the coast, Mass. to Tex.; W. Ind.

18, GIFOLA Cass.

1. Gifola germanica (L.) Dumort. HERBA IMPIA.
Collected at Mount Vernon, Occoquan Creek, and on High Island. May-Sept.
Native of Eur.; naturalized in the eastern U.S. (Filago germanica L.)

19. PLUCHEA Cass.

1. Pluchea camphorata (L.) DC. MARSH FLEABANE,
In marshes; Mount Vernon and Marshall Hall. Aug.-Sept. Mass. to Mex.
A coarse annual, with small clustered heads of purplish flowers.

20. ANTENNARIA Gaertn. EvER.LASTING. Pussy-TOEs.

Inflorescence consisting of a single head. Stem very slender, with a few appressed
linear leaves......-..-- 2-2 - ee ee eee eee cece cence ee eeeeee .-l. A. solitaria.
Inflorescence consisting of several or numerous heads, those of the pistillate plants in
corymbs or racemes.
Plants relatively small; mature basal leaves mostly 1.5-4 cm. long, 5-10 mm.
broad, with only the midvein conspicuous above.
Stolons mostly short, leafy throughout, forming broad mats; leaves obovate,
abruptly wedge-shaped to the narrowly winged petiole...... 2. A. neodioica.
Stolons long, slender, with well-developed leaves only at the tip; leaves oblan-
ceolate, often broadly so, passing gradually into the broadly winged petiole.
3. A. neglecta.
Plants much larger and stouter; mature basal leaves of pistillate plants 5-12 cm.
long, 2-4 cm. broad, with 3 well-defined main nerves evident above.
Upper surface of basal leaves bright green, usually glabrous at all stages, some-
times slightly cobwebby when young.................+---- 4. A. arnoglossa.
Upper surface of basal leaves dull green, closely covered with a thin tomentum,
this partially persistent to the following year.
Plants very robust; mature basal leaves 2-4 cm. broad; pistillate inflorescence
subcapitate or densely corymbose, the heads averaging about 1 cm. high.
5. A. fallax.
Plants comparatively slender; mature basal leaves narrower (1.5-3 cm. broad);
pistillate inflorescence loosely corymbose (often diffusely so with age), the
heads averaging about 8 mm. high............-.------ 6. A. plantaginifolia.

1. Antennaria solitaria Rydb.
Damp sterile rocky banks, usually in the shade of beeches; several localities, mostly
from Rock Creek Park eastward. May. Pa. to Ohio, south to the Gulf states.

2. Antennaria neodioica Greene.

Open fields, brushy banks, and open woods, often under pines; fairly common
throughout. May. Northeastern N. Amer.

The local form, described as A, alsinoides Greene, does not seem specifically distinct.

284 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

3. Antennaria neglecta Greene.

Pastures, old fields, meadows, and roadside banks; abundant throughout. Apr.—May.
Northeastern N. Amer., south to Va.

The staminate plants mostly precede the pistillate.

4. Antennaria arnoglossa Greene.

Open or partially shaded grassy slopes or old meadows, occasionally in damp thickets;
abundant. May. N. Eng. to Va. and westward.

Staminate plants are rare. This species was described from local material; it may
not be separable from A. parlinii Fernald.

5. Antennaria fallax Greene.

Open, moist or dryish fields or pastures or at border of woods; general, but much
less common than the last, which it closely resembles in most characters and from
which it may not be distinct. Apr.—May. Eastern U.S.

6. Antennaria plantaginifolia (L.) Richards.

Stony slopes, in thin shade of pines or beeches, or sometimes on open grassy hill-
sides; abundant throughout. Apr.—May. Eastern U.S. (A. decipiens Greene.)

The staminate plants are abundant, in contrast to the last two species.

21. GNAPHALIUM L.

Leaves glabrous or nearly so on the upper surface, densely white-woolly beneath,
usually acute or acuminate, broadest at or near the middle; heads short-stalked,
in corymbs, the bracts white or brownish; pappus bristles distinct, falling sep-
arately; plants usually 60 cm. high or more................-. 1. G. obtusifolium.

Leaves copiously woolly on both surfaces, or sometimes glabrate on the upper surface
in age; heads sessile, in spikes or dense clusters; plants mostly low, only rarely
60 cm. high and usually much lower.

Stem leaves linear or nearly so, acute or acutish; heads clustered, whitish; pappus

bristles distinct; stems much branched...............--.-.-- 2. G. uliginosum.

Stem leaves spatulate, obtuse; heads spicate, usually purplish; pappus bristles
united at the base; stems mostly simple.................... 3. G. purpureum.

1. Gnaphalium obtusifolium L. EVERLASTING.

Dry open fields; common. July-Sept. Eastern N. Amer. (G. polycephalum
Michx.)

2. Gnaphalium uliginosum L. Low CUDWEED.

Wet meadows; near Le Droit Park and sources of Piney Branch (Ward); not col-
lected since 1884. Widely distributed in N. Amer.

8. Gnaphalium purpureum L. PuRPLISH CUDWEED.

Open fields or low ground; frequent. May-Sept. Eastern U. S. and in tropical
Amer.

A single specimen of G. spathulatum Lam., native of the Gulf states, was collected
in the Department of Agriculture Grounds, Oct., 1898 (Steele). This species resembles
G. purpureum, but the stems gre usually branched, the leaves thin, and the heads
densely woolly.

Inula helenium L., elecampane, a native of Europe, was reported by Knowlton
from Mount Vernon, It is a tall coarse perennial with large yellow heads. Jnula
brittanica L., also of Europe, was collected along the Pennsylvania Railroad, southeast.
of H Street Bridge, July and Aug., 1915 (J. B. S. Norton).

FLORA OF THE DISTRICT OF COLUMBIA. 285

22. POLYMNIA L.

Rays 5, obovate or wedge-shaped, shorter than the bracts or but slightly exceeding
them, yellowish white; lower leaves pinnately lobed; achenes 3-ribbed, not

Striate... 2. ee ee ee ee cee cee eee eee ene eneees 1. P, canadensis.
Rays 10-15, narrowly oblong, much longer than the bracts, yellow; lower leaves
palmately lobed; achenes conspicuously striate.....-.--------- 2. P. uvedalia.
1. Polymnia canadensis IL. SMALL-FLOWERED LEAFCUP.

Damp woods along the Potomac above Washington; common. July—Oct. Eastern
U.S.
2. Polymnia uvedalia L. LARGE-FLOWERED LEAFCUP.
Damp woods along the Potomac; common. Aug.-Oct. Eastern U.S.

23. ACANTHOSPERMUM Schrank.

1. Acanthospermum australe (Loefl.) Kuntze. SPINY-BUR.

On the Virginia side of the Potomac half a mile beyond the railroad bridge, on the
railroad embankment; plants forming a patch 4.5 by 6 meters which has persisted
several years. Va. to La.; widely distributed in tropical regions.

24, SILPHIUM L.

Silphium laciniatum L., a native of the western and southern states, with pinnati-
fid leaves, was reported by Holm as having been found at Woodley Bridge; the
plant has now disappeared.

1. Silphium trifoliatum L. ROSIN-WEED.
Woods or open fields; frequent. July-Aug. Eastern N. Amer.
A tall perennial with glabrous stems, finely toothed leaves, and large heads of yel-
low flowers. In general appearance it resembles some of our species of Helianthus,
but it is easily distinguished by the broad bracts.

25. CHRYSOGONUM L.

1. Chrysogonum virginianum L. GOLDEN STAR.
Woods; common. Apr.-June; sometimes flowering in early or late autumn.
Southern Pa. to Fla. a

The variety dentatum described by Gray ' scarcely deserves nomenclatorial recogni-
tion. It is supposed to have deltoid-ovate, acute, dentate-serrate, rather than ovate,
obtuse, crenate leaves, but in these respects there is no constant difference. It was
described from material collected on High Island.

26. PARTHENIUM L.

1. Parthenium integrifolium L.

Collected but once, on a dry hillside near the Hyattsville Swamp, in 1909 (Standley). |
Eastern U.S.

A coarse rough-hairy perennial with small heads of whitish flowers.

27. HELIOPSIS Pers.

1. Heliopsis helianthoides (L.) Sweet. OX-EYE.
Woods; chiefly along the Potomac. July-Sept. Eastern U.S. (H. laevis Pers.)
A coarse perennial with large heads of yellow flowers.

1 Bot. Gaz. 7: 31. 1882.

286 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

28. ECLIPTA I.
1, Eclipta alba (L.) Hassk.

Wet ground; common along the Potomac. July-Oct. Widely distributed in the
U.8., doubtless naturalized northward; common in most tropical regions. ( Verbesina
alba L.; E. procumbens Michx.)

An inconspicuous annual with small heads of white flowers.

29. RUDBECKIA L.

Stems glabrous, or with a few minute appressed hairs just below the heads; rays
drooping, bright yellow; receptacle elongate in fruit; disk flowers greenish
yellow; lower leaves pinnately lobed.............2.20.2-.-0000- 1. R. laciniata.

Stems copiously hairy; rays spreading; receptacle not elongate in fruit; disk flowers
deep purple; leaves 3-lobed or merely toothed.

Chaff of the disk long-acuminate, glabrous; lower leaves 3-lobed, sparsely hairy.

Rays orange-yellow........2...0. 0.220 c cee ee cece ecececceececeee 2. R. triloba.
Chaff of the disk obtuse or acutish, pubescent; leaves merely toothed or entire.

Chaff of the disk densely and finely hairy; rays bright yellow; leaves densely

hairy; pappus none..............0 0.0 cece eee eee cece ceceeeee 3. R. hirta.

Chaff of the disk minutely hairy on the margin, otherwise glabrous; rays usually

ora@mge-yellow; leaves sparsely hairy; pappus a low crown...... 4. R. fulgida,

1. Rudbeckia laciniata L. TALL CONE-FLOWER,
Wet soil, often at the edge of water; common... Aug.—Oct. Widely distributed in
N. Amer.
The golden glow, so common in cultivation, is a form of thisspecies with “double”
flowers, that is, the usually inconspicuous d isk flowers have assumed the form of rays.
Double- flowered plants are sometimes found wild.

2. Rudbeckia triloba L.
Woods along the Potomac above Washington. July—Oct. Eastern U. S.
8. Rudbeckia hirta L. BLACK-EYED SUSAN.
Woods and open fields; common. June-Sept. Nearly throughout the U. S. and
southern Can.; adventive eastward.
4. Rudbeckia fulgida Ait. ORANGE CONE-FLOWER.
Dry woods: common. Aug.-Oct. Southern states, north to N. J.
The plants are somewhat variable, especially in leaf form, probably as a result of
varying conditions as to moisture and light.

30. HELIANTHUS L. SuNFLOWER.

Leaves linear or nearly so, entire, sessile or subsessile. Stems hairy below and about
the inflorescence; disk flowers purple; bracts linear-lanceolate, scabrous.
1. H. angustifolius.
Leaves lanceolate or broader, usually toothed.
Stem leaves sessile, opposite.
Stems glabrous except about the inflorescence; leaves spreading, lanceolate,

sparsely hairy beneath, truncate at the base.............. 2. H. divaricatus.
Stems densely hairy; leaves ascending, ovate, densely soft-hairy beneath, cordate
at the base........ 2.0... eee ee cee eee eee ceecceecees 8. H. mollis.

Stem leaves petioled.
Plants annual; leaves alternate; disk of the head 2.5 cm. wide or often much
broader. Stems hairy..................0222cce cece e cece eee 4. H. annuus.

FLORA OF THE DISTRICT OF COLUMBIA. 287

Plants perennial; leaves mostly opposite; disk 2 cm. wide or smaller.

Leaves mostly crowded near the base of the stem, the upper ones distant and
much reduced. Leaves ovate to lance-ovate, thick and firm, finely
toothed, glabrous or nearly so; bracts shorter than the disk flowers, acute
or acutish, finely hairy on the margin, usually glabrous on the outer face.

5. H. dowellianus.

Leaves evenly distributed along the stems, the upper ones not much smaller
than the lower.

Stems glabrous except about the inflorescence.

Leaves pale beneath, soft to the touch, finely hairy, lanceolate or oblong-
lanceolate, obscurely and finely toothed or entire; bracts about as long
as the disk flowers..........--------- ee eee eee eee 6. H. strumosus.

Leaves green on both sides, rough-hairy beneath, ovate or lance-ovate,
conspicuously toothed; bracts much longer than the disk flowers.

7. H. decapetalus.
Stems copiously hairy throughout.

Leaves not 3-nerved, lanceolate, short-petioled, mostly alternate.

8. H. giganteus.

Leaves 3-nerved, ovate, long-petioled, mostly opposite....9. H. tuberosus.

1. Helianthus angustifolius L. SWAMP SUNFLOWER.
Wet ground; northeast of Washington. Sept.—Oct. Eastern U. 8.

2. Helianthus divaricatus L.

Woods and open fields; common. July-Sept. Eastern N. Amer.
3. Helianthus mollis Lam.

Open fields near Cabin John, Riverdale, and Hunting Creek; perhaps adventive.
Aug.-Sept. Eastern U.S.
4. Helianthus annuus L. COMMON SUNFLOWER.

Waste ground about Washington; infrequent. Aug. Native of the western U. S.;
frequently escaped from cultivation or adventive eastward.
5. Helianthus dowellianus M. A. Curtis.

Dry hillsides; Little Falls, High Island, and Rock Creek Park. Aug.—Sept. Md.
to Ga. (H. occidentalis dowellianus Torr. & Gray; H. occidentalis of Ward’s Flora. )
6. Helianthus strumosus L.

Woods; frequent. Sept. Eastern U.S.

Helianthus strumosus mollis Torr. & Gray is a form with the leaves more pubescent
beneath.
7. Helianthus decapetalus L.

Damp woods; common. July-Oct. Eastern N. Amer.
8. Helianthus giganteus L.

Wet ground; frequent. Sept.-Oct. TEastern N. Amer., west to Colo.
9. Helianthus tuberosus L. JERUSALEM ARTICHOKE.

Low ground or marshes; frequent along the Potomac. Sept.-Oct. Eastern N.
Amer. (H. doronicoides of Ward’s Flora.)

The Jerusalem artichoke, the tubers of which are used for food, is derived from
this plant.

31. RIDAN Adans.

1. Ridan alternifolius (L.) Britton. YELLOW IRON-WEED.
Damp or wet woods; frequent. Aug.-Oct. Eastern U.S. (Verbesina alternifolia
- Britton; Actinomeris squarrosa Nutt.; A. alternifolia DC.)
A tall coarse perennial with medium-sized heads of yellow flowers having 2 to 8
small unequal yellow rays.

288 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

82. VERBESINA L.

1. Verbesina occidentalis (L.) Walt. YELLOW CROWNBEARD.
Woods and fields, chiefly in alluvial soil; frequent. Aug.—Oct. Southeastern
U.S. (Phaethusa occidentalis Britton; V. siegesbeckia Michx.)
A tall perennial with small heads of yellow flowers. In general appearance much
like Ridan alternifolius, but readily distinguished by the wingless achenes.

33. COREOPSIS L.

Plants hairy; stem leaves mostly simple and entire, narrowly lanceolate or oblanceo-

late.... 2... cece cee eee eee eee eee ee ee cece eee e cee eeeeeee 1. C. crassifolia.
Plants glabrous; stem leaves all or nearly all compound.

Leaves petioled, divided into 3 or 5 lanceolate to linear-lanceolate leaflets, or the

uppermost simple; plants 1-2 meters high; pappus none...... 2. C. tripteris.
Leaves sessile, parted into numerous linear-filiform segments; plants usually less
than 60 cm. high; pappus of 2 short teeth................. 8. C. verticillata.

Coreopsis tinctoria I. was reported by Ward as escaped in a few places but has not
been collected recently. It is an annual plant, native of the western U. 8., common
in cultivation and frequently escaped.

1. Coreopsis crassifolia Ait.
Escaped in a few localities. Native of the southeastern states; often cultivated.
(C. lanceolata villosa Michx.)
2. Coreopsis tripteris L. TALL TICKSEED.
Woods along the Potomac above Washington; frequent; also on Occoquan Creek
and near Falls Church. July-Sept. Eastern U. S.
8. Coreopsis verticillata L. WHORLED TICKSEED.
Thin woods and open fields; common. June-Oct. Eastern U.S.

34. BIDENS L.

Leaves lanceolate, simple, toothed.
Rays present; heads usually nodding in fruit.
Rays much longer than the bracts; leaves finely and equally toothed, usually free

at the base; achenes 6-9 mm. long..........-......--------- 1. B. laevis.
Rays mostly shorter than the bracts; leaves coarsely and unequally toothed,
usually united at the base; achenes 5-6 mm. long.............- 2. B. cernua.

Rays none; heads erect.
Pappus awns upwardly barbed. Outer bracts 4 or 5, leaflike; leaves coarsely
toothed; inner achenes less than 2 mm. broad..........-. 3. B. bidentoides.
Pappus awns downwardly barbed.
Outer involucre of 4 or 5 short entire bracts; achenes 4-6 mm. long, angled.
4. B. connata.
Outer involucre of 6-8 toothed leaflike bracts; achenes about 1 cm. long, flat.

5. B. comosa,
Leaves pinnately parted or dissected, or the uppermost simple.

Rays large and showy. Plants hairy; leaves with 5-7 linear-lanceolate, sharply
toothed leaflets; achenes flat, more than 2 mm. broad.......... 6. B. aristosa.
Rays none or inconspicuous.
Leaves dissected into numerous small lobes; achenes linear, 4-angled.

7%. B. bipinnata.
Leaves composed of 3 or 5 large leaflets; achenes flat.

Outer bracts 10-16; achenes brown, 3.3-4 mm. broad .......... 8. B. vulgata.
Outer bracts 4-8; achenes black.
Inner achenes less than 2 mm. broad; heads about 5 mm. high.9. B. discoidea.
Inner achenes 2-3.3 mm. broad; heads 10-15 mm. long......10. B. frondosa.

FLORA OF THE DISTRICT OF COLUMBIA. 289

1. Bidens laevis (L.) B.S. P. BUR MARIGOLD,
Wet ground; occasional. Sept. Eastern U.S. (B. lugens Greene; B. chrysanthe-
mordes Michx.)
2. Bidens cernua L. BUR MARIGOLD.
Wet ground; common. Aug.—Oct. Nearly throughout the U. 8. and southern
Can.; also in Eur, and Asia.
3. Bidens bidentoides (Nutt.) Britton. SWAMP BEGGAR-TICKS.
Wet ground; near Cabin John, Aug.-Sept. N. J. to Md.
4. Bidens connata Muhl.
Swamp near Hyattsville. Sept. Eastern U.S.
5. Bidens comosa (A. Gray) Wiegand.
Swamps or wet ground; common. Aug.-Sept. Eastern U. 8.
6. Bidens aristosa (Michx.) Britton.
Wet ground along the Potomac. and at Chesapeake Junction. Aug.-Sept. East-

. em U.S.

7. Bidens bipinnata L. SPANISH NEEDLES.
Woods;common, Sept.-Oct. Eastern U.8., west to Ariz.

8. Bidens vulgata Greene.
Woods; frequent. Aug.-Oct. Widely distributed in N. Amer.

9. Bidens discoidea (Torr. & Gray) Britton.
Holmead Swamp and Bennings. Sept. Eastern U. 8. (Coreopsis discoidea Torr.
& Gray.)
10, Bidens frondosa L. BEGGAR-TICKS.
Damp woods or fields; common, Aug.—Oct. Nearly throughout the U. 8. and
southern Can.
35. GALINSOGA Ruiz & Pav.

Rays reddish; pappus of the disk flowers about half aslongas the achenes. Pubescence

copious, of loose spreading hairs................-.---------- 1. G. caracasana.
Rays white; pappus of the disk flowers about as long as the achenes.

Pappus scales of the disk flowers rather obtuse; pubescence of somewhat appressed

hairs... 2. ee ce ce ee ce eee eee eee e ee eeeee 2. G. parviflora.
Pappus scales of the disk flowers very acute, bristle-tipped; pubescence of loose
and spreading hairs..............2...0.622-022e00e ee 2a. G. parviflora hispida.

1. Galinsoga caracasana (DC.) Schultz Bip.

In a cornfield along the Potomac near Great Falls, August 7, 1910 (F. W. Pennell).
Native of tropical Amer.; reported as adventive in Md. and N. J.
2. Galinsoga parviflora Cav.

Waste ground and cultivated fields; frequent. June-Oct. Native of tropical
Amer.; adventive in many parts of the U. 8.
2a. Galinsoga parviflora hispida DC.

Waste ground about Washington and in fields near Great Falls. Aug.-Oct. Na-
tive of tropical Amer.; adventive in the eastern U. S.

36. HELENIUM L.

Disk of the heads yellow; leaves elliptic-lanceolate to ovate-lanceolate, toothed.
1. H. autumnale.

Disk purple; leaves lanceolate or linear-lanceolate, usually entire.
2. H. nudifioram.

69289—19——19

290 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

1, Helenium autumnale L. SNEEZEWEED.
Wet meadows; common. Aug.—Oct. Nearly throughout the U. S. and southern
Can.

2, Helenium nudiflorum Nutt. PURPLE SNEEZEWEED.
Collected above Plummers Island, east of Chevy Chase, and near Beltsville. July-
Sept. N.C. to Tex., adventive northward.

87. ACHILLEA L.
1. Achillea millefolium L. YARROW.
Woods, open fields, and roadsides; abundant. June-Aug. Eastern N. Amer.;
also in Eur. and Asia.
Characterized by the finely dissected, plumelike, strong-scented leaves. The rays
are often tinged with pink.
38. ANTHEMIS L.

Plants ill-scented; leaves thrice pinnately lobed; receptacle without chaff near the

margin; achenes roughened.............0.- 202-22 eee eee ee ee eee 1. A. cotula,
Plants not ill-scented; leaves once or twice pinnately lobed; chaff subtending all
the disk flowers; achenes smooth.............2..--0---2-ee-eeeeeee 2. A. arvensis.
1, Anthemis cotula L. MayYWwEED. Doa FENNEL.

Waste ground; common. June-July. Native of Eur.; widely naturalized in N.
Amer. (Maruta cotula DC.)

2. Anthemis arvensis L. CoRN CAMOMILE.
Waste and cultivated ground; common. May-July. Native of Eur., widely
naturalized in the U. §.
Anthemis tinctoria L., a European species with yellow rays, was collected at College
Park in 1915 (J. B. S. Norton).

89. CHRYSANTHEMUM L.
The common cultivated chrysanthemums belong to this genus.

1, Chrysanthemum leucanthemum pinnatifidum Lecog.& Lam. Ox-rYE palsy.
Fields; very abundant. May-Oct. Native of Eur. and Asia; widely naturalized
inthe U.S. (Leucanthemum vulgare of Ward’s Flora.)
Chrysanthemum parthenium (L.) Bernh., feverfew, has been found a few times in
‘waste ground about Washington. Native of Eur.; adventive or escaped from culti-
vation locally in the U. S. and southern Can.
Chrysanthemum balsamita L., costmary, was collected in waste ground at Fifteenth
Street and Florida Avenue, September, 1899 (Steele). Native of the Old World;
sparingly escaped from cultivation in the eastern U. S.

40. TANACETUM IL.
1. Tanacetum vulgare IL. TANSY.
Occasional on roadsides and in waste ground. July-Aug. Native of Eur.; often
naturalized or escaped from cultivation in the U. 8.

41. ARTEMISIA L.
1. Artemisia annua L. ANNUAL WORMWOOD.

Waste ground about Washington and Alexandria and at Glen Echo. Aug.-Sept
Native of Asia; adventive or escaped from cultivation in many parts of the U. 8.

An annual plant with sweet-scented foliage.

Artemisia caudata Michx. was reported from the vicinity of Alexandria, by Holm.
No specimens have been seen by the writer. Artemisia vulgaris L. was collected
along a roadside near Rosslyn, August, 1899 (Steele). Native of Eur. and Asia; adven-
tive in the eastern U. 8.

FLORA OF THE DISTRICT OF COLUMBIA. 291

42, ARNICA L.
1. Arnica acaulis (Walt.) B.S. P. LEOPARD’S-BANE.
Sandy woods north and east of Washington and at Broadwater. May-Aug. South-
eastern U.S. (A. nudicaulis Ell.)
A showy plant with large heads of yellow flowers and long yellow rays.

43. ERECHTITES Raf.

1. Erechtites hieracifolia (L.) Raf. TIREWEED.
Moist woods or fields. Aug.-Sept. Widely distributed in N. and S. Amer.
A coarse annual with narrow heads of whitish flowers. It is often found in
burned-over areas, hence the common name.

44, MESADENIA Raf. INDIAN PLANTAIN.

Leaves glaucous beneath, the uppermost with a few large lobes. .1. M. atriplicifolia.
Leaves green beneath, the uppermost with numerous teeth......... 2. M. reniformis.

1, Mesadenia atriplicifolia (L.) Raf.

Woods; frequent. June-Sept. Eastern U.S. (Cacalia atriplicifolia L.)
2. Mesadenia reniformis (Muhl.) Raf.

High Island, June 6, 1880 (Ward); probably now extinct. Eastern U.S. (Cacalia
reniformis Muhl.)

45. SYNOSMA Ralf.

1. Synosma suaveolens (L.) Raf.

Low ground or damp woods along the Potomac; frequent. Aug.—Oct. Eastern
U.S. (Cacalia suaveolens L.)

A tall glabrous perennial with triangular leaves and small heads of whitish flowers
in corymbs.

46. SENECIO L.

A specimen of Senecio vulgaris L., an annual European species, was collected in

the Department of Agriculture grounds in 1873 ( Vasey).

Basal leaves cordate at the base, about as broad aslong............----.- 1. S. aureus.
Basal leaves not cordate at the base, rounded or tapering, often much longer than
broad.
Basal leaves broadly obovate..........-.-------- eee e eee e eee ees 2. S. obovatus.
Basal leaves not obovate, rounded or oblanceolate-oblong.
Stem leaves lobed nearly or quite to the midrib; basal leaves oblanceolate-

oblong; stem very woolly at the base........-....--...--..-. 3. S. smallii.

Stem leaves usually coarsely toothed, not lobed to the midrib; basal leaves
rounded; stem nearly or quite glabrous at the base....... 4. S. crawfordil.

1. Senecio aureus L. GOLDEN RAGWORT.

Damp woods and wet meadows; common. Apr.-May. Eastern N. Amer.
2. Senecio obovatus Muhl.

Reported from Great Falls by Greenman;! no specimens seen by the writer. Enaat-
ern U.S.
8. Senecio smallii Britton.

Thin woods and open fields; comnmion. May-June. Pa. to Ala. (S. aureus bal-
samitae of Ward’s Flora.)

Two of our specimens were determined as S. pauperculus Muhl, by Greenman, but
they seem not to differ from others determined as S. smallii.
4. Senecio crawfordii Britton.

White gravel bog, southeast of Suitland. May. Pa., N. J., and Md.

1 Ann. Mo. Bot. Gard. 8: 111. 1916.

292 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

47. ARCTIUM L.
1. Arctium minus Schkubr. Burpock.
Waste ground; common. May-July. Native of Eur.; widely naturalized in the
U.S. (Lappa officinalis of Ward’s Flora.)
Arctium tomentosum (Lam,) Schkuhr, with very woolly heads, was collected in
waste ground about Washington, June, 1896 (Steele). Native of Eur.

48. CIRSIUM Mill. TuistLe.

Leaves glabrous or nearly so, green.
Heads 2.5 cm. broad or smaller; perennial, with rootstocks; bracts with very
short spiny tips......-......-..2..22 22sec eee eee eee eee eee 1. C. arvense.
Heads 5-7 cm. broad; biennial, without rootstocks; bracts with slender spiny tips.
2. C. odoratum.
Leaves densely white-woolly, at least beneath.
Bracts not ending in spines. Leaves pinnately lobed, white-woolly beneath when
young, sometimes nearly glabrous in age; heads on naked stalks.
3. C. muticum.
Bracts ending in spines.
Bracts all ending in spines. Leaves pinnately lobed, the lobes triangular, end-

ing in sharp spines.............-..---------- eee eee eee 4. C. lanceolatum.
Bracts only in part (the outer ones) ending in spines, the inner acuminate.
Peduncles naked or nearly so. Leaves deeply lobed. ...... 5. C. virginianum.
Peduncles leafy, the heads subtended by leaves.
Leaves deeply lobed, the lobes lanceolate or linear.......... 6. C. discolor.

Leaves merely toothed, or the lowest sometimes shallowly lobed.
7. C. altissimum.

1. Cirsium arvense (1..) Scop. JANADA THISTLE.
Waste ground; infrequent. June-Aug. Native of Eur.; widely naturalized in the
U. S. and often a troublesome weed. (Carduus arvensis Robson; Cnicus arvensis

Hoffm.)

2. Cirsium odoratum (Muhl.) Britton. PASTURE THISTLE.
In woods; Woodley. June. Me. toW. Va. (Cardwus odoratus Porter.)

8. Cirsium muticum Michx. SWAMP THISTLE.
Above Cowdens, Sept., 1914 (Steele). Eastern N. Amer. — (Cardwus muticus Pers.)

4, Cirsium lanceolatum (L.) Hill. COMMON THISTLE.

Fields and pastures; infrequent. July-Oct. Native of Eur. and Asia; widely
naturalized in the U.S. (Carduus lanceolatus L.; Cnieus lanceolatus Willd.)
5. Cirsium virginianum (L.) Michx. VIRGINIA THISTLE.
Wooded hillside along Difficult Run, June, 1915 (Standley). Southeastern U.S
(Carduus virginianus L.)

6. Cirsium discolor (Muhl.) Spreng. FIELD THISTLE.
Dry woods; frequent. Aug.—Sept. Eastern U.S
7. Cirsium altissimum (L.) Spreng. TALL THISTLE.

Moist woods and copses; common. July-Oct. Eastern U. 8.

Carduus nutans L., musk thistle, was collected-in waste ground in southwest Wash-
ington in 1897. Native of Eur. and Asia; naturalized locally in the northeastern U.S.

49. ONOPORDON L.
1. Onopordon acanthium L. ScoTcH THISTLE.
Waste ground about Washington and Alexandria, frequent about the latter place
and well established. Native of Eur. and Asia; adventive in the northeastern U. S.

FLORA OF THE DISTRICT OF COLUMBIA. 293

50. CENTAUREA L.

Besides the species entered below, each of the following, all natives of Europe, bas
been collected once in our region: Centaurea solstitialis L., Vienna, July, 1909 (C. £.
Shear); C. vochinensis Bernh.., ions the Pennsylvania Railroad, southeast of the H
Street Bridge, 1915 (7. B. 8. Norton); C. nigra L., Daniels Road, July, 1914 (Steele):
C. jacea L., Franklin Park anc Pinehurst. None of them, probably, is established.

Bracts ending in long stout spines; heads sessile; leaves with spiny lobes and teeth.

1. C. calcitrapa.
Bracts not spiny; heads stalked; leaves not spiny.

Stem leaves all divided into linear lobes.....................-.-. 2. C. maculosa.
Stem leaves all or mostly entire..................2.-.-2-----------. 3. C. cyanus.
1. Centaurea calcitrapa L. STAR THISILLE.

Abundant in waste ground at Alexandria; occasional about Washington. May-
Sept. Native of Eur.; adventive in the eastern U.S.
2. Centaurea maculosa Lam. 7

Collected near Mullikin and at Franklin Park; perhaps not established.: July—Aug.
Native of Eur.; occasionally adventive in the eastern U.S.
3. Centaurea cyanus L. CORN-FLOWER.

Occasional in waste ground and grain fields. Native of Eur.; often cultivated for its
showy blue, pink, or white flowers.

Known also as bluebottle and bachelor’s-button.

SUMMARY OF THE LARGER GROUPS, WITH NUMBERS OF GENERA
AND SPECIES.

Genera.| Species. Genera.|Species.

PTERIDOPHYTA. MONOCOTYLEDONEAE—CON,
Ophioglossaceae........-- 2 4 || Melanthiaceae.............. 7 9
Osmundaceae........----- 1 3 || Liliaceae..............---- 7 15
Schizaeaceae.............-. 1 1 || Convallariaceae...........-- 6 8
Polypodiaceae......... ..--| 17 35 || Smilacaceae..........-.---- 1 6
Equisetaceae............-. 1 2 || Amaryllidaceae...........-- ] 1
Lycopodiaceae..........-. 1 7 || Dioscoreaceae.............. 1 2
Selaginellaceae............. 1 2 || Iridaceae.................- 3 9
Tsoetaceae..........-.....-- 1 2 || Orchidaceae............... 16 31

GYMNOSPERMAE. DICOTYLEDONEAE.

Pinaceae.......-..----.---- 4 9 || Saururaceae..........---.- 1 1
| Salicaceae.........--------- 2 15
MONOCOTYLEDONEAE. | Myricaceae..........-...-- 2 2
| Juglandaceae....-....---- 2 7
Typhaceae........----.---- 1 2 || Betulaceae..........-.---- 5 6
Sparganiaceae............-. 1 | 3 | Fagaceae.........--.-.4--- 3 23
Fotamogetonaceae cece eee 2 13°) Ulmaceae........-.------ 2 5
Naiadaceae........--------- | 1 2 | Moraceae......--.---------- 3 4
Alismaceae............20-- 3 9 | Urticaceae............-.--- 7 8
Vallisneriaceae..........-. | 2 2 | Loranthaceae............-- 1 1
Poaceae........... eee ee eee 57 186 | Santalaceae.............-.- 1 1
Cyperaceae...........---.-- 13 155 | Aristolochiaceae............ 2 2
Araceae@......2-.222222 2206 5 6 || Polygonaceae..............- 8 28
Lemnaceae.....-..-.----5- 3 3 || Chenopodiaceae.......-..-- 3 7
Xyridaceae..............-- 1 2 || Amaranthaceae............. 3 8
Eriocaulaceae......------ 1 2 || Allioniaceae............... 1 1
Commelinaceae......-....- 2 4 || Phytolaccaceae.............- 1 1
Pontederiaceae......-.-..-- 2 3 || Aizoaceae.........-.----.- 1 1
Juncaceae......... see eeeee 2 16 ! Portulacaceae............-- 3 3

294

CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

SUMMARY OF THE LARGER GROUPS, WITH NUMBERS OF GEN-

ERA AND SPECIES.—Continued.

DICOTYLEDONEAE—contd.

Corrigiolaceae..............
Alsinaceae.......
Silenaceae
Nymphaeaceae.............
Cabombaceae...............
Ceratophyllaceae.......-...
Ranunculaceae............
Berberidaceae
Menispermaceaeé...........
Magnoliaceae...............
Annonaceae
Lauraceae.
Papaveracege..........-.--
Fumariaceae...............
Brassicaceae............---.
Capparidaceae.........-...
Sarraceniaceae.............
Droseraceae

ee a es

Crassulaceae................
Penthoraceae
Saxifragaceae...............
Hydrangeaceae...........-
Escalloniaceae.............-
Grossulariaceae............
Hamamelidaceae...........
Platamaceae..............--

Malaceae.................-
Amygdalaceae........... ..
Caesalpiniaceae.............
Fabaceae...........-.-.-+-
Oxalidaceae...............-
Linaceae..............--.--
Rutaceae............------
Simaroubaceae.............
Polygalaceae..............
Euphorbiaceae...........--.
Callitrichaceae..........-.
Limnanthaceae...........--
Anacardiaceae.............
Aquifoliaceae..............
Celastraceae.......... .
Staphyleaceae..........-...
Aceraceae..... cee eee eeacees
Impatientaceae............
Rhamnaceae.............2.
Vitaceae...........20002..0.
Malvaceae................-
Hypericaceae..............
Elatinaceae................
Cistaceae........-.
Violaceae..................

Genera.

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Species.

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| Haloragidaceae...........-.

DICOTYLEDONEAE—Contd.

Daphnaceae................
Lythraceae................
Melastomataceae..........

Onagraceae................-
Araliaceae...........2222--
Apiaceae
Cornaceae............2.2008
Clethraceae

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Pyrolaceae...............-.
Monotropaceae..........-.
Ericaceae........... seeeee

Vacciniaceae..............5
Primulaceae ............--
Diospyraceae |

— Oleaceae..... 22.2.2... 2 eee |
- Loganiaceae............4.
| Gentianaceae.............. |

_ Apocynaceae
| Asclepiadaceae.............

| Cuscutaceae...........2..--

| Boraginaceae..............

| Bignoniaceae.............

| Rubiaceae

| Dipsacaceae. .........2.--

_ Campanulaceae......-....

| Ambrosiaceae.............

| Pteridophyta.............

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Convolvulaceae.........-.
Polemoniaceae
Hydrophyllaceae..........

Verbenaceae............-.
Menthaceae
Solanaceae... ...........-.
Scrophulariaceae

Orobanchaceae............
Pinguiculaceae............

Acanthaceae
Phrymaceae.........-.-...
Plantaginaceae............

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Valerianaceae........
Cucurbitaceae...........-.

Lobeliaceae...............
Cichoriaceae.... 2.2.22...

Asteraceae

SUMMARY.

Spermatophyta:
Gymnospermae.........
Angiospermae—

Monocotyledoneae......
Dicotyledoneae........

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489
1,076

1, 630

Of the species formally listed 287 have been introduced from other regions, chiefly
from Europe. In addition, there are mentioned incidentally 108 species which have

been found only as waifs.

FLORA OF THE DISTRICT OF COLUMBIA. 295

GLOSSARY.

Abortive. Imperfectly developed; defective.

Acaulescent. Stemless, or with the stem subterranean.

Achene. A small dry one-seeded one-celled indehiscent fruit.

Acuminate. Tapering at the end; long-acute.

Acute. Terminating sharply in an angle of less than 90 degrees.

Adherent. Joined to some other organ but structurally distinct from it.

Adnate. Attached by one side or by its surface to a different organ or part.

Adventive. Imperfectly naturalized.

Aerial. Referring to above-ground organs or parts, as contrasted with those below
ground.

Aggregate. Said of ‘‘polymorphous”’ species or groups of individuals not well under-
stood and suspected of including several distinct species or subspecies.

Alternate. Not opposite; arising singly at different heights.

Ament. A catkin or spike with flexible axis, usually scaly.

Anastomosing. Connecting by branches or cross veins, forming a network.

Annual. Maturing from seed germinated within the year; of one year’s duration
only.

Anther. The pollen-bearing part of the stamen.

Anthesis. The time of opening of a flower.

Antrorse. Directed upward.

Apetalous. Lacking petals.

Appressed. Lying closely against another organ or part.

Approximate. Situated close together, but not united.

Arcuate. Bowlike; lightly curved.

Aristate. Awned or bristle-tipped.

Articulate. Jointed.

Ascending. Directed obliquely upward, or curving upward.

Attenuate. Long-tapering, becoming slender or very narrow.

Auricled. Having earlike appendages or basal lobes.

Awl-shaped. Attenuate from the base to a slender or rigid point; subulate.
Awn. A bristle-like organ or appendage; in grasses, the continuation of the nerves
of the bracts of the spikelet, sometimes stout and variously twisted, rarely trifid.
Azil. The angle formed between the axis and any leaf, branch, or organ arising
from it.

Axillary. Arising from an axil; borne at an axil.

Beaked. Ending in an elongate, comparatively stout tip.

Bearded. Bearing long hairs in tufts or over small areas; barbate.

Berry. A fruit with fleshy pericarp.

Bidentate. Having two teeth; or,as to margins, doubly toothed.

Biennial. Maturing during the second year from seed.

Bifid. Cleft into two parts.

Bilabiate. Two-lipped.

Bilobate. Two-lobed.

Bipinnate. Twice pinnate, that is, the primary divisions of a pinnate organ again
pinnate.

Bipinnatifid. Twice pinnatifid, that is, the primary divisions of a pinnatifid organ
again pinnatifid.

Blade. The expanded part of a leaf, sepal, or petal.

Bract. A more or less modified leaf subtending a flower, flower cluster, or sporangium.

Bracteate. Having bracts.

Bracteolate. Having bractlets.

296 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Bracteole. Bractlet.

Bractlet. A secondary bract, borne on the pedicel of a flower.

Bristle. A long stiff hair or hairlike organ.

Bulb. A leaf bud (usually subterranean), with fleshy scales or coats.

Bulblet. A small bulb, particularly one borne upon the stem.

Bullate. Appearing as if blistered.

Caducous. Falling off very soon after development.

Callus. A hard or indurate projection; in grasses, the base of the mature floret, the
callus being sharp and pilose in such genera as Stipa and Aristida.

Calyx. The outer series of perianth parts.

Campanulate. Bell-shaped.

Canescent. Hoary, with fine gray pubescence. °

Capillary. Hairlike.

Capitate. Borne in a head or dense cluster.

Capsule. A dry dehiscent fruit formed of two or more carpels.

Carinate. Keeled; with a more or less sharp longitudinal ridge.

Carpel. The modified leaf forming a simple ovary, or one member of a compoun:!
ovary.

Cartilaginous. Firm and tough; cartilage-like.

Caruncle. A wartlike appendage to a seed at or near the hilum.

Caryopsis. The dry indehiscent one-seeded fruit of grasses, in which the pericarp is
adherent to the seed, as the grain of wheat or corn.

Catkin. See ament.

Caudate. Having a slender taillike tip or terminal appendage.

Caulescent. Producing a stem above ground.

Cauline. Pertaining to the stem.

Cell. The cavity of an anther or ovary.

Cespitose. Growing in tufts; tufted.

Chaff. Dry bracts.

Chartaceous. Of papery texture.

Chlorophyll. The green coloring matter of plants.

Ciliate. Fringed with hairs on the edge.

Circumscissile. Dehiscing transversely, the top separating like a lid.

Claw. The greatly narrowed base of some petals.

Cleft. Cut about half way to the midvein or base.

Cleistogamous. Producing seed from flowers which are self-fertilized in the bud,
the floral envelope not opening.

Cochleate. Spiral, like a snail shell.

Compound. Composed of two or more like parts joined together. Compound leaf,
one divided into separate leaflets. Compound ovary, one composed of two or more
carpels.

Conduplicate. Folded lengthwise.

Cone. A compact series of overlapping scalelike carpels, arranged about a common
axis.

Confluent. Running together; blended in one.

Coniferous. Cone-bearing.

Connate. Said of similar organs more or less completely joined to each other.

Coralloid. Resembling coral.

Cordate. Heart-shaped; with two rounded lobes at base.

Corivaceous. Of leathery texture.

Corm, An enlarged solid fleshy base of a stem.

Corolla, The inner series of perianth parts.

Corymb. A flat-topped or convex open flower cluster, with the pedicels arising from
different points on the stem, the outer flowers blooming earliest.

FLORA OF THE DISTRICT OF COLUMBIA. 297

Corymbose. Borne in a corymb; corymb-like,

Cotyledon. A rudimentary leaf of the embryo within the seed.

Creeping. Extending along or just below the surface of the ground and rooting.

Crenate. Scallopéd; with rounded teeth.

Crenulate. Minutely crenate.

Crested. Provided with a raised crestlike appendage.

Crisped. Ruffled, as if having an excess of leaf tissue.

Crown. An inner appendage to a petal or to the throat of a corolla; the perennial
portion of a herbaceous plant above the root; a low cuplike border terminating an
achene or other organ.

Cucullate. Hoodlike, or provided with a hood.

Culm, The flowering stem of sedges and grasses,

Cuncate. Wedge-shaped.

Cuspidate. Tipped with a cusp or sharp stiff point.

Cyme. <A flat-topped or convex flower cluster, the central flowers blooming earliest.

Cymose, Arranged in cymes; cymelike.

Deciduous. Falling away; not evergreen.

Decompound. More than once compound.

Decumbent. Reclining, but with the end ascending (applied to stems and branches),

Decurrent. Extending down upon another part and adhering to it below the point
of attachment.

Definite. Of a constant number.

Defleced. Bent or directed abruptly downward.

Dehiscent. Opening by valves, slits, etc., to discharge the contents,

Deltoid. Broadly triangular, like the Greek letter A.

Dentate. Toothed, the teeth commonly acutish, nearly equal-sided, and projecting
at a right angle.

Denticulate. Minutely dentate.

Depressed. Flattened from above.

Diadelphous. The stamens combined in two sets.

Dichotomous. Forked regularly into two nearly equal branches.

Dicotyledonous. Having two cotyledons.

Diffuse. Loosely spreading, the branches usually numerous.

Digitate. Compound, the similar parts radiating from a common point; also said of
the spikes or spikelike racemes of grasses when approximate by the shortening of
the rachis at the summit of the culm.

Dimorphous. Occurring in two forms.

Divecious. Unisexual, the staminate and the pistillate flowers borne on different indi-
viduals.

Discoid. Disklike, or lacking ray flowers.

Disk. An enlargement of the receptacle of a flower around the base of the pistil;
also, the head of tubular flowers in Asteraceae, etc.

Dissected. Cut or finely divided into numerous lobes or segments.

Distichous. Arranged in two rows, more especially when this arrangement is con-
spicuous. ~

Distinct. Separate from each other; evident.

Divaricate. Diverging at a wide angle.

Divided, Lobed to the base or midvein.

Dorsal, Borne upon or relating to the back or outer surface of an organ.

Drupe. A fleshy or pulpy fruit, the inner portion of the pericarp hard and stony.

Echinate. Beset with prickles.

Ellipsoid. A solid body, elliptic in lengthwise section.

Elliptic. With the outline of an ellipse; narrowly oval.

Emarginate. Shallowly notched at the end.

298 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Embryo. The rudimentary plant within the seed.

Emergence. An outgrowth involving subepidermal tissue.

Endocarp. The inner layer of the pericarp.

Endosperm. The nutritive substance surrounding the embryo of a seed.

Entire. Without divisions, lobes, or any marginal cutting.

Epicarp. The outer layer of the pericarp or matured ovary.

Epiphyte. A plant growing upon another plant, but not organically connected
with it.

Equitant. Astride; referring to conduplicate leaves which enfold each other in two
ranks,

Erose. Unevenly toothed, as if gnawed.

Estipulate. Lacking stipules.

Evergreen. Bearing green leaves at all seasons of the year.

Excurrent. Projecting beyond the main part of the organ.

Exfoliating. Peeling off naturally in thin layers.

Exocarp. The outer layer of the pericarp.

Exserted. Projecting beyond the surrounding organs, especially stamens from a
corolla.

Extrorse. Facing or directed outward, as the openings of an anther.

Falcate. Shaped somewhat like the blade of a scythe; curved and flat, usually taper-
ing toward the tip.

Fascicle. A close bundle or cluster of like organs having a common source.

Fastigiate. Referring to stems or branches which are erect and close together.

Fertile. Bearing organs or elements essential to reproduction.

Fertilization. The complete fusion of a male and a female reproductive cell.

Fibrous. Fiber-like or composed of fibers.

Fibro-vascular. Composed of woody fibers and ducts.

Filament. The part of a stamen which bears the anther.

Filamentous. Composed of threadlike structures.

Filiform. Threadlike; long, slender, and terete.

Fimbriate. Fringed.

Flabellate. Fan-shaped, either in outline or in venation.

Flagellate. With the apex slenderly prolonged into a whiplike tail.

Fleruous. Zigzag; bent or curved alternately in two directions.

Floccose. With loose tufts of woollike hairs.

Floret, A small flower, usually one of a head or dense cluster; in grasses, the flower
with its inclosing lemma and palea.

Foliaceous. Leaflike in texture, appearance, or function.

Foliolate. Consisting of separate leaflets. .

Foliose. Leafy; leaflike.

Follicle. A simple fruit composed of one carpel, dehiscing along one suture.

Free. Entirely separate from other organs; (in venation) not at all joined.

Frond. The leaf of ferns and some other cryptogams or, loosely, of palms or fern-
like plants; also, in Lemnaceae, the expanded leaflike stem.

Fruit. The seed-bearing product of a plant, of whatever form.

Fugacious. Of temporary duration; falling or fading soon after development.

Furcate. Simply forked; once forked.

Fuscous. Dusky brown.

Fusiform. Spindle-shaped; tapering from the middle toward each end.

Gamopetalous. Having the petals more or less united.

Geniculate. Abruptly bent like a knee.

Gibbous. Humped or swollen on one side.

Glabrate. Nearly glabrous, or becoming so.

Glabrous. Devoid of hairs.

FLORA OF THE DISTRICT OF COLUMBIA. 299

Gland. A secreting cell or cellular structure.

Glandular. Glandlike, or bearing glands.

Glaucous. Covered with white or bluish bloom.

Globose. Spheric or essentially so.

Glomerate. Compactly clustered.

Glomerule. A small dense cyme.

Glume. One of the lowest pair of bracts in the spikelet of grasses.

Gregarious. Growing in groups of several to many individuals.

Habit. The general appearance of a plant.

Habitat. The characteristic environment of a species.

Halberd-shaped. Same as hastate.

Hastute. Shaped like an arrowhead, but with the basal lobes pointing outward.

Head. A dense cluster of sessile or nearly sessile flowers.

Herb. A plant with no persistent woody stem above ground.

Herbaceous. (1) Having the characters of an herb, as opposed to a woody or partly
woody plant; (2) leaflike in texture and color; (3) of a firm, rather brittle consist-
ency, breaking readily.

Hilum. The sear or small area of attachment of a seed.

Hirsute. With rather coarse or stiff straight hairs.

Hirtellous. Minutely hirsute.

Hispid. With stiff or bristle-like hairs.

Hispidulous. Minutely hispid.

Hood. <A concave form of petal or sepal resembling a monk’s hood.

Hyaline. Translucent.

Hybrid. The offspring from crossing two species.

Imbricate. Partially overlapping or, in a flower bud, at least one segment wholly ex-
ternal and one internal.

Imperfect. Pertaining to flowers which lack either stamens or pistils; unisexual.

Incised. Cut sharply and rather deeply, often irregularly.

Included. Not protruding from the surrounding organs.

Indefinite. Of uncertain number or very numerous.

Indehiscent. Not opening spontaneously.

Indigenous. Native to the region.

Indurate. Hardened.

Indusium. The small, often membranous, special structure covering the sorus in
ferns.

Inequilateral. Unequal-sided.

Inferior. Situated below another organ; more particularly referring to an ovary adher-
ent to the calyx.

Inflated. Bladder-like.

Inflorescence. The flowering portion of a plant; the mode of arrangement of the flowers.

Infra-. A latin prefix signifying below; as infra-stipular, below the stipules.

Insertion. The mode of attachment of one organ to another; the position of an organ
relative to another.

Internode. The portion of a stem or branch between two nodes.

Involucel. A secondary involucre, as in the Apiaceae .

Involucrate. Having an involucre.

Involucre. A whorl of distinct or united bracts or leaves subtending a flower or flower
cluster.

Involute. Rolled inward from the margins upon the upper surface.

Irregular. Referring to flowers whose corresponding parts are unequal in size, form,
or structure.

Keel. The two lower united petals of a papilionaceous flower; the midnerve of a
compressed floral bract in grasses and sedges.

300 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Keeled. Provided with a more or less sharp longitudinal ridge, like the keel of a boat

Lacerate. lrregularly cleft, as if torn.

Laciniate. “Slashed”; cut into slender pointed segments.

Lanceolate. Lance-shaped; 3 or 4 times as long as broad and tapering from the basal
third to a narrow apex.

Leaflet. A single division of a compound leaf.

Legume. The fruit of Caesalpiniaceae and Fabaceae, one-carpeled, usually dry,
two-valved, and dehiscing along the back.

Leguminous. Pertaining toa legume, or to the families Fabaceae and Caesalpini-
aceae.

Iemma, The outer bract of the floret of grasses, called also the flowering glume.

Lenticular. Taving the shape of a double-convex lens.

Tigule. A strap-shaped corolla, as in the ray flowers of Asteraceae; also, in grasses
and a few other families, an appendage, usually membranaceous, on the inner side
of the junction of the sheath and blade.

Limb. The expanded portion of a gamopetalous corolla or calyx above the throat.

Innear. Many times longer than broad, and with the sides parallel or nearly so.

Lip. The upper or the lower division of a bilabiate corolla or calyx; the peculiar
upper (apparently lower) petal in Orchidaceae.

Lobed. Divided to about the middle, or bearing lobes.

Lunate. Crescent-shaped.

Lyrate. Pinnatifid and having the terminal lobe rounded and much larger than the
others.

Megasporangium. The receptacle in which megaspores develop.

Megaspore. The larger of two kinds of spores borne by a plant, particularly in certain
families of Pteridophyta, giving rise to the female prothallium.

Membranaceous. Thin, membrane-like, and somewhat translucent.

Micropyle, Orifice of the ovule, and the corresponding point on the seed.

Microsporangium. The receptacle in which microspores develop.

Microspore. The smaller of the two kinds of spores borne by a plant, especially in the
Pteridophyta, giving rise to the male prothallium.

Midrib. The principal, usually middle, rib of a leaf.

Midvein. The middle vein ofa leaf or other leaflike organ.

Monadelphous. Referring to stamens united by their filaments into a tube or column.

Monocotyledonous. Waving a single cotyledon.

Monoecious. Waving stamens and pistils in separate flowers on the same plant.

Mucro. A short straight abrupt tip.

Mucronate. Ending ina short straight abrupt tip.

Multifid. Very treely and deeply cut into narrow segments or lobes.

Muricate. Rough with short hard prominences.

Naked. Lacking organs or protective parts normally present in related species
or genera.

Naturalized. Not native, but having become thoroughly established as a part of the
flora of a region.

Node. The point upon a stem at which a leaf or whorl of leaves is borne, frequently
hard and thickened.

Nodose. Marked by numerous or conspicuous nodes; knobby or knotty.

Nodulose. Marked by small knotlike or knublike nodes or by partitions.

Nut. An indehiscent one-celled one-seeded fruit with a hard or bony pericarp.

Nutlet. A diminutive nut; one of the achene-like parts of the fruit of Boraginaceae,
Verbenaceae, Menthaceae, etc.

Ob-. A Latin prefix, usually signifying inversion.

Obconie. Inversely conic, being attached at the slender end.

Oblanceolate. Inversely lanceolate, the broadest part being above the middle.

FLORA OF THE DISTRICT OF COLUMBIA. 301

Oblique. Slanting; making an acute angle with the axis,

Oblong. Longer than broad, with the sides nearly parallel.

Obovate. Inverted-ovate.

Obovoid. Inverted-ovoid.

Obsolete. Not evident; in a rudimentary or vestigial state.

Obtuse. Not sharply pointed; blunt or rounded at the end.

Ocreex, The membranous, sheathing, united stipules of Polygonaceae.

Opaque. Dull; not shining or translucent.

Opposite. Referring to leaves or similar organs which arise on the stem in twos, one
on each side of the node; also. one part above or before another, as a stamen in
front of a petal.

Orbicular. Essentially circular.

Ovary. The ovule-bearing part of the pistil.

Ovate. Having the outline of a hen’s egg in longitudinal section. with the broad end
downward.

Ovoid. Shaped like a hen’s egg.

Ovule. The body which after fertilization develops into the seed.

Palea. The bract of a floret of grasses standing between the flower and the rachilla
or axis of the spikelet.

Palet. See palea.

Palmate. Referring to organs which are radiately lobed or divided, suggesting the
outspread fingers of the hand.

Panduriform. Fiddle-shaped.

Panicle. A compound inflorescence with pedicellate flowers; the compound fertile
parts of certain dimorphous ferns and fern allies.

Paniculate. Borne in a panicle; resembling a panicle.

Papilionaceous. Referring to the peculiar irregular corolla of the Fabaceae, consisting
of standard, wings, and keel.

Papillose. Bearing minute blunt protuberances.

Pappus. The peculiar calyx limb of Asteraceae, etc., surmounting the achene and
commonly bristle-like, awnlike, or feathery.

Parasitic. Growing on other organisms and deriving nourishment from them.

Parietal. Borne on the wall of a capsule, or pertaining to it.

Parted. Cleft nearly to the base.

Parthenogenetic. Developing without the agency of fertilization.

Pectinate. Regularly pinnatifid into numerous narrow, closely set segments; having
organs or members arranged in a pectinate or comblike manner.

Pedate. Palmately divided or parted, but having the lateral segments two-cleft.

Pedicel. The support of a single flower of a flower cluster; in grasses, the support of
a single spikelet.

Pedicellate. Borne on a pedicel.

Peduncle. A main flower stalk supporting a flower cluster or a solitary flower.

Pedunculate. Borne upon a peduncle.

Pellucid. ‘Transparent or somewhat so.

Peltate. Attached to its stalk at some point of the lower surface, instead of at the
margin.

'Pendulous. More or less hanging.

Percurrent. Extending throughout the entire length of the organ.

Perennial. Living year after year.

Perfect, Referring to flowers which have both pistil and stamens,

Perfoliate. Referring to leaves whose clasping bases are united, as if pierced by
the stem.

Perianth. The floral envelope, consisting of the calyx and corolla, however incom-
plete or modified.

302 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Pericarp. The walls of the fruit; the matured ovary wall.

Perigynium. The membranous, often inflated sac inclosing the ovary or‘achene in
the genus Carex.

Persistent. Referring to organs which after the growing period remain attached to the
parts bearing them.

Petal. A division of the corolla.

Petaliferous. Bearing petals.

Petiolate. Furnished with a petiole.

Petiole. The stalk by which the blade of a leaf is attached to the stem.

Pilose. Provided with soft hairs.

Pinna. A primary division of a pinnately compound frond or leaf; leaflet.

Pinnate. Referring to compound leaves, with the segments or leaflets arranged on
each side of a common axis.

Pinnatifid. Pinnately lobed or cleft to the middle or beyond.

Pinnule. A division of a pinna; a secondary pinna.

Pistil. The seed-producing organ of a flower, consisting of ovary, style, and stigma
(or the style wanting).

Pistillate. Referring to flowers which are provided with pistils but not with stamens,
and to individual inflorescences and plants having only pistillate flowers.

Pitted. Having numerous small depressions.

Placenta. Any ovule-bearing part of the ovary.

Plaited. Same as plicate.

Plano-conver. Flat on one side and convex on the other,

Plicate. Folded into regular elongate plaits, like a fan.

Plumose. Feather-like, with fine hairs on each side.

Plumule. The bud of the embryo.

Pod. The popular name for a dry dehiscent fruit, especially a legume.

Pollen. The fecundating granules developed within the anther.

Polygamous. Bearing both perfect and imperfect flowers.

Polypetalous. Having the petals distinct from each other.

Pome. The fleshy fruit of the apple family.

Prickle. A stiff sharp-pointed emergence.

Procumbent. ‘Trailing or lying on the ground, but without rooting at the nodes.

Proliferous. Reproducing vegetatively by buds, bulblets, or offshoots.

Prostrate. Lying flat upon the ground.

Prothallium. The inconspicuous sexual stage of the Pteridophyta, giving rise to the
spore-bearing plant known as a fern or fern ally.

Puberulent. Very finely pubescent.

Pubescent. Covered with short hairs.

Punctate. Dotted with small depressions or translucent glands,

Pungent. Ending in a sharp stiff point. r

Quadrate. Nearly square in form.

Raceme. A form of inflorescence in which the pediceled flowers are borne upon an
elongate axis.

Racemose. In racemes, or resembling a raceme.

Rachilla, A little rachis or axis, applied especially to the axis of the spikelet of
grasses.

Rachis. The axis of a compound leaf or of an inflorescence.

Radiate. Spreading from a common center; bearing ray flowers.

Radical. Arising from the root or the base of the stem.

Radicle. The rudimentary stem of the embryo below the cotyledons; called also
hypocotyl or caulicle.

Ray. The branch of an umbel; the marginal flowers of an inflorescence in composites
when different from those of the disk.

FLORA OF THE DISTRICT OF COLUMBIA. 303

Receptacle. The somewhat enlarged end of the flower stalk upon which numerous
flowers or the organs of a flower are borne.

Recurved. Curved downward or backward.

Reflexed. Bent back or down abruptly.

Regular. Having members of the same kind alike in shape, size, or structure.

Reniform. Kidney-shaped.

Repand. Referring to an uneven, somewhat sinuate margin, or to leaf blades that are
wavy or “‘fluted” toward the margin. ,

Reticulate. Net-veined; like a network.

Retrorse. Directed back or downward.

Retuse. With a shallow notch at the end.

Revolute. Rolled backward from the margin or apex upon the lower surface.

Rhachilla. See rachilla.

Rhizome. Same as rootstock.

Rib. A main or prominent leaf vein; a raised fine or ridge on fruit or other organs.

Root. The underground part of the plant which supports it and provides it with
nourishment from the soil.

Rootstock. A prostrate or subterranean stem, usually emitting roots at the nodes.

Rostrate. Having a stiff beaklike tip.

Rotate. Wheel-shaped, referring to a corolla or calyx which has the spreading limb
flattish and circular in outline.

Rotund. Roundish; nearly orbicular.

Rugose. With wrinkled surface.

Runner. A slender stolon.

Sac. A pouch, especially the cavity of an anther.

Saccate. Pouchlike; provided with a pouch or sac.

Sagittate. Shaped like an arrowhead, with the acutish basal lobes directed down-
ward.

Salient. Directed outward (referring to marginal teeth).

Salverform. Salver-shaped, referring to corollas having the slender tube very abruptly
expanded into a flat limb.

Samara. An indehiscent winged fruit.

Saprophyte. A plant which grows on dead organic matter.

Scabrous. Rough to the touch.

Scale. A reduced leaf at the base or beginning of a shoot; in sedges, the bract sub-
tending the flower; in Asteraceae, etc., the bracts on the receptacle at the side
of (below) each flower.

Scape. A leafless or nearly leafless peduncle arising from the underground parts of a
plant.

Scapose. Bearing a scape, or resembling one.

Scarious. Thin, dry, and membranaceous, and not green.

Secund. Apparently borne along one side of an axis (usually referring to flowers).

Seed. The ripened ovule, consisting of the embryo and its coverings.

Segment. A natural division of an organ or structure, as of a separating fruit.

Sepal. A division of the calyx.

Septate. Provided with partitions.

Sericeous. Very closely covered with fine appressed soft straight hairs of silky
appearance.

Serrate. Having sharp teeth directed forward.

Serrulate. Finely serrate.

Sessile. Attached directly, without a stalk of any kind.

Setaceous. Bristle-like.

Setose. Beset with bristles.

304 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Sheath. The lower tubular part of a leaf inclosing the stem, especially in grasses
and sedges.

Shoot. A stem with its leaves and other appendages.

Silique. The peculiar long two-valved capsule of the Brassicaceae.

Silky. See sericeous.

Simple, Undivided; not compound.

Sinuate. With the outline of the margin strongly wavy.

Sinus. The angle between two lobes.

Smooth. Unarmed; without roughness due to spines, tubercles, or coarse outgrowths

Sorus. A group or cluster of sporangia, as in the ferns.

Spadix. Aspike with a fleshy axis.

Spathe. One or more large bracts subtending or inclosing an inflorescence, espe
cially a spadix.

Spatulate. Gradually narrowed downward from a rounded apex.

Spicate. Spikelike or arranged in a spike.

Spike. An elongate inflorescence or branch of an inflorescence with the flowers
sessile or nearly so.

Spikelet. A small or a secondary spike, particularly as applied to the flower
clusters of grasses and sedges.

Spine. A rigid sharp-pointed outgrowth of a plant, being a modified stem or leaf.

Spinulose. Minutely spiny; applied loosely also to margins with variously awned
teeth.

Sporangium. A spore case.

Sporophyll. The leaf subtending the sporangium in certain of the fern allies, or the
specialized spore-bearing leaf parts as a whole.

Spreading. Diverging nearly at right angles.

Spur. A hollow, saclike or tubular extension of a floral organ.

Squarrose. Having the parts or appendages wide-spreading.

Stamen. The organ of a flower which bears the pollen grains.

Staminate. Stamen-bearing.

Staminodium. A sterile stamen, or any similar sterile structure corresponding to it.

Standard. The broad upper petal of a papilionaceous corolla, as, for example, in a
pea blossom.

Stellate. Star-shaped, the slender segments or divisions radiating from a common
center.

Stem. The main leafy axis of a plant.

Sterile. Without functioning reproductive organs; in the ferns, without sporangia.

Stigma. The tip or other part of a pistil through which fertilization by the pollen
grains is accomplished.

Stipe. The stalklike support of an organ or part; more especially, the leaf stalk
of a fern.

Stipitate. Distinctly stalked; provided with a stipe.

Stipulate. Having stipules.

Stipule. One of a pair of appendages borne at the base of certain petioles, or these
sometimes united.

Stolon. <A trailing basal branch rooting at the nodes.

Stoloniferous. Producing stolons.

Stramineous. Straw-colored.

Striate. Minutely grooved or furrowed.

Strict. Perfectly straight and upright.

Strigose. Beset with appressed straight stiff hairs.

Style, The usually slender portion of the pistil connecting the stigma with the ovary.

Sub-. A Latin prefix, usually signifying somewhat, slightly, or nearly.

Subacute. Acutish; somewhat acute.

FLORA OF THE DISTRICT OF COLUMBIA. 305

Subcordate. Shallowly two-lobed, referring to the base.

Subcoriaceous. Somewhat leathery in texture.

Subulate. Awl-shaped.

Succulent. Juicy, fleshy.

Suffrutescent. Slightly shrubby.

Sulcate. Grooved or furrowed lengthwise.

Superior. Situated above another organ; more particularly referring to an ovary
which is free from the calyx.

Suture. A line of splitting or dehiscence.

Symmetrical. Referring to flowers which have the same number of members in each
whorl.

Tendril. A slender, leafless, spirally coiled organ of attachment developing from
modified stems or leaves.

Terete. Circular in cross section; cylindric or nearly so.

Ternate. Arranged in threes.

Thorn. A stout spine.

Throat. The orifice of a gamopetalous corolla or calyx; the orifice of any tubular
organ, as of a sheath in grasses.

Thyrse. A contracted, cylindrical or ovoid and usually compact panicle.

Thyrsoid. Resembling a thyrse.

Tomentose. With a dense woollike covering of closely entangled, matted hairs.

Tomentulose. Sparingly or minutely tomentose.

Tomentum. A close matted covering of entangled woollike hairs,

Toothed. Furnished with marginal teeth of various form; more exactly, dentate.

Trifoliolate. Having three leaflets.

Triquetrous. Sharply three-angled, the sides concave or channeled.

Truncate. Terminating abruptly, as if cut off crosswise.

Tuber. A short thickened underground branch having numerous buds.

Tubercle. A small tuber or tuber-like body; a small wartlike excrescence; the per-
sistent base of the style in certain Cyperaceae.

Tuberculate. With small wart-like projections.

Tuberous. Tuber-like in appearance; having the characteristics of a tuber.

Turbinate. Inversely conical; top-shaped.

Turgid. Thick, as if swollen by sap.

Umbel. An indeterminate inflorescence in which the peduncles or the pedicels of a
cluster arise from a common point, the outer flowers blooming earliest.

Umbellate. Borne in umbels; umbel-like.

Uncinate. Hooked; resembling a hook.

Undulate. With wavy surfaces, especially toward the margins; repand.

Unguiculate. Having a contracted clawlike base.

Uniserual. Referring to flowers wholly of one sex, either staminate or pistillate.

Urceolate. Hollow and urn-shaped, constricted near the mouth.

Utricle. A small bladdery one-seeded fruit; any small inflated body.

Valvate. Meeting by the margins in the bud, without overlapping; opening by
valves, as a capsule.

Valve. One of the segments into which a capsule splits.

Vascular. Provided with vessels or conducting tissue.

Veinlet. A branch of a vein.

Veins. The smaller branches of vascular tissue forming the framework of the leaf.

Venation. The arrangement of the veins.

Ventricose. Swelling unequally; inflated on one side.

Vernation. The arrangement of leaves or leaf parts in the bud.

69289—19——20

306 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM.

Verrucose. Covered with wartlike prominences.

Versatile. Fixed at a point near the middle and thus swinging freely (referring to an
anther).

Verticillate. Arranged in a whorl.

Vesicle. A small bladder-like air cavity.

Vestigial. Referring to structures or organs which function incompletely if at all,
being in the nature of vestiges or remnants of their former condition.

Villous, Beset with long soft weak hairs.

Virgate. Wandlike; slender, straight, and erect.

Viscid. Sticky to the touch; glutinous.

Whorl. An arrangement of three or more leaves or other organs in a circle about a
common axis.

Whorled. See verticillate.

Wing. Each of the two lateral petals of a papilionaceous corolla; any thin expansion
bordering an organ or part.

Winged. Provided with a thin expanded border.

Woolly, Clothed with long, tortuous or branched, usually entangled hairs.

INDEX.

[Synonyms in italic.)

Page

Bo 0) re 61
Abutilon... 2... .. cece cece ec cence cee eceeee 203
Acalypha.............. eee c cence cece eceeeces 195
Acanthaceae............. wee eee ese eeeeenaee 255
Acanthospermum. ..............0..c0cece0e- 285
Acanthus family..............-....0-0-eeeee- 255
CC) 200
ACCTACERE. 2... cece cece cece cece cee eeee 200
ACOTAtES... 2... eee eee cece eee eee e ee 231
Achillea. 2.2.0.0... cece eee eee cece eeeeees 290
ACHrOGNEhES 00... ec cece ce cece cece cee eeecauee 131
Acnida... 2... cecal c cece ce cece ee eee 149
Aconitum ...... 0.0... ccc eee cece eee eee 157
BC) 0: 114
Actinomeris......... we cece cece cece cece ee ceeee 287
Adder’s-mouth. ........ 2... eceeececee cence 131
Adder’s-tongue.............0.. ccc ece eens 52, 122

family....... 0... eee eee eee ee 52
Adiantum..............0 2... .c cece cece eee eeee 55
Eo 143
AdOPOGON. 00... cc cece ccc cence cece cece ce ceee 264
Aesculacease.... 2.2.2... cece cece cece eeeee: 200
Aesculus. ... 2.2.2... cece cece eee ceeeeeces 200
Agalinis. 2.0... .... 0c. cc cece cece cece eee eee 253
Agastache. ..........0.. 2. ccc cece cece eee 242
ARAVE 2... cece cece cence e ce cenecs 125
Agrimonia.............0cccececuceeeencecuees 176
Agrimony....... 0... cece cece e eee w ee eee 176
ASTOPYTON........... 0.00 e cece cece eee eee eee 90
Agrostemma..................-. we eeeeeeceeee 153
Agrostis. 2.22... 0. ccc eee e cece ecw e cence 83
7.01: eet e cece cece cecceeeeeeees 84
Aidlanthus... 2.2.2.0... 20sec cece cece eee cess 193
AizOaCORe.. 0.2... 6c eee cece ees eeeeecececaces 150
AjUZO... cece a eee e cee n cece eee eeee 241
Alchemilla..........c0ce.ee0- wee cece eeneeee 177
Alder. ...............0.. 0000 ene ce ee cenenecee 137

black. 0... eee cece eee ec eee cence cee 199
Aletris... 2.0.0.2... cece eee eee ees ececesecee 122
0 ¢:) 0 ¢: 183
Alfileria. 2.0.02. 0. c cece eee eee cee eee 190
00 01: 64
Alismaceae. .... 2.0... eee eee cece ee cece eee 64
Alliaria... 0.0... cece cece cece cee eee eeee 167
Alliomia... 0... eee cece eee eee ne ee 149
Allioniaceae. . 2.2... c cece cece cece ence rece 149
Allium. 222... eee e cece ee eeee 121
Almond family ............2.0220..ceeceeeeee 179
AIMUS. 200. ee cece ce ee eee e eee ee eeeee 137
Alopecurus..........0.0 2 cee eee eee eee eee eee 83
Alsike clover............ wee e cece e eee eee eeecee 184
Alsinaceae..........-0-0 ee cence cece cece rece 151
Alsine..........-.- 0-0 e eee cece eee eee eee eee 152
Althaea........... 20. e cece cece cece eee eee eeee 202

shrubby........-.------ eee eee eee eee eee 203

Page.

Alum-root.... 2.20.0 .ccecececeeececeeeceee --- 171
Alyssum, sweet...... ween ccc eee cee ecetececes 165
Amaranth, common...............0.000-000- 149
family.... 2.2... cece eee cece eeecuccecacee 148
0) 0 149
Amaranthaceae...........-..0cececeeceecucet 148
AmMAranthuS............ cece cece eee e cece ceeee 149
Amaryllidaceae............... 2... e cece eens 125
Amaryllis. 0.0.0... 20 ccc cece cee eee eees 125
family... 22.2... cece eee eee cece eee eee 125

i 1618) c0).) 0; ne 268
Ambrosiaceae. ........0.....022- eee e eee ----- 267
Amelanchier... 2.2.0.2... 20 cece eee eee e eee 178
American aspen............-.- eee ceceeereeee 134
prooklime. 2.2... eee eee ee eee 252
purnet...... wee tee cece cen weet wees eeees 177
Code of Botanical Nomenclature......... 16
crab apple..............ce cece ene e ee eeee 177
Le 141
holly . 2.2.20. e eee eee eee cece cece eee eees 199
hornbeam....... wee cece wee ee ee eaeneee 136
pemnyroyal. ...........e cece cece eee eeee 244
wormseed.......... wasn cece cece ee eeeee 148
Amianthium..........-.-2..-.--22 2 esse eee eee 120
AMMANNIG .... cea c eee e ence teen eee eeeeeeeees 212
Amorpha..........0ceeeeeeeeee ence eee ceceees 184
AMpelanus.... 2.02. cece eee e eee eee ewes 231
Ampelopsis...........-..0---0-0-e- eee eeee 170, 202
Amphicarpa ......---2---0-eee cece cece eee eeee 189
Amygdalaceae..........-.-...-.-4- eceeecaeee 179
Amygdalus.......-...-0-.-2-e eee ee ee eee eee -. 179
Anacardiaceae..........-.-...- wee e ce enseces 198
Amacharis......-...-.-0-0-e ee cece ence cee eeee 66
Amagallis. ........-..0- eee e cece eee eee eee 226
Anchistea. . 2.2.0... cece ence eee eee e eee eeees 55
AMNGTOMENA.... 6. ccc cece wecseeeweeee weeeeeeee 223
Andropogon... ........... cece eee eeees sesecee 71
AMNOMONE.... 2... ee eee eee cece eee 157
Tue...... wee ene cece cane nec ceeeeeeneeess 157
20010 157
Anemonella.........- eee eee cece eee e eee eee 157
Angelica..........c cece cece cere cece ceeeceees 218
bc: 215
Angle-pod... 2.22... -.. eee eee eee cece eee 231
AMMONACEAE.... 2... ee ee eee eee ee eee eee ee 161
Annual wormwood....... wee e cece cece eee 290
Antenmaria. ......-...-e eee ee eee eee ee eee 283
Anthemis. ...........20.000- eee eee eee eeeee 290
Anthoxanthum.............-.-eeeeee eee eee 81
Anychia............00206 cece ete eee eee eees 151
Apargia.. 2... se. cece eee eee eee e cece eee e ee 264
Aphanes...........-..+-- ween cece eecnceee --- 77
Aphylion....... cece cece cece cece eee ceeeeee 255
Apiaceae... .............0-5 cee c weet eee c ees 215
Apios..........- eee ce sesecneccnrneneeseces 189

308 INDEX.
Page. Page
Aplectrum. ............. 0.2. eee eee eee eee 132 | Aster, New England ...........-.........0-. 281
APOCYNACODE. ... 2.2. eee eee ee eee eee 229 red-stalked . 0.2.2.2... ce eee ee cence ec eeee 281
APOCYNUM. 2.2.0... cece eee cece cece eee cece 230 Silver... 0.22... cece eee eee eee eee eee eee 281
Apple, crab... 22.2... eee ee eee ee eee eee ee 177 SMOOth...... 2... eee eee eee eee eee ee eee 281
family... 2.2.02... ce ee eee ee eee eee eee 177 white wood........... ose e cence eeereeenes 280
C0) 0 Bd) a) ae 247 white-topped.......... 0... c cece eee eee ee 278
Aquifoliaceae.........-..-.. cece eee eee eee eee 199 | Asteraceae... 0.2... cece cece cece cece ee ee eee 268
Aquilegia........... 2.2 e eee eee eee ee eee 157 | Astragalus..........2.0..2 2. cece ee eee eee 185
Arabidopsis........... 2... ce cece cece eee eees 168 | Athyrium........ 2... eee eee eee ee eens 56
716: 0) (a 168 | Atriplex... 2... cece cece wees 148
ATACCOC. 2... eee eee ee ee enc cee eeeeee 113 | Aureolaria............. 0.0 c cece eee eee ee eee 253
Aralia... 2.0.0.2... ccc cceecceeeeeeenneeeeees 215 | Austrian pine........ oe eeececseeenenssereneds 61
Araliaceae ... 2.0... 2. cece cece ee cece ees 215 | AVeMa....... cece cece eee e cece ceuececuceaucs 85
Arbutus, trailing. ................2...00000ee 222 | AVONS.......... 0c cece cece cece eee cece eens 175
Archangelica.......02......0005: be eeceeeeeees 218 | Awnless brome grass.............0eesseeeeees 90
ATCheMOrd.. 2... ccc ccc cence enc ccucccccccscce 918 | Azalea... ... 2... eee cece cece cence eneeece 223
Arctium... 2... e eee cece ence eens 292 PINK... cece cee cence ences 223
Area included by flora...............cceceees 15 SWAMP. ... 2-2... e eee cece ence eee eens 223
Arenaria.......... ween cence cece eee eeeenceeee 153 | Baccharis................ 0 ccc cece eee eee eees 283
Arethusa. 2.22.20... 0 cece eee eee eee en es 130 | Bachelor’s-button....................2000005 293
Arisaema..............- cece eeeeeeeccuseucecs 113 20 Co 193
ATiStidd 02... cece cece cc cece cee n eee cccceeeees B1 | Bacopa......-..... cece eee eeee cece cece eens 251
Aristolochia. ............0.. cece cece ence eee 143 | Bald cypress............0.cccecececccecuceces 61
Aristolochiaceae..............02.ceccenceeues 143 | Ball, C. RB... occ eee eee eee eee 14
Armoracia.. 0.2... eee cece nce e ec cen eect 166 | Balloon vine............2 222. ee eee ee cece ees 201
Fa (c: 291 | Balm, garden................cesseeeecesecees 244
B10) 0) C: 178 Of Gilead .... 2.2.0... eee eee cee eee eee 135
Arrhenatherum...............ccceeeeeececees 85 | Baptisia................ 222 eee eee eee es 182
AITOW ATUM... 2.2... eee eee eee ee eee eee eee 114 | Barberry..................... cee eeaeeeeeees 160
Arrowhead. ..............ccccceeeeecceeeecus 65 16:3 00) 0) 160
Arrow-leaf violet... ...........02.02... cee eee 209 | Barley.......... 002.22 cece eee cece ence ce ees 91
ATTOW-WO00d... 222. o eee ee cece een eee ees 260 BTASS... 2.2222 eee ee eee eee teen enneee 91
Artomisia.... 2.0.2.2... cee cca c cece ee eeeeeees 290 | Barnyard grass.................... we eeeeeees 80
Arthraxon.... 2... ccc eee ccc e ee eeee 71 | Bartonia........ ccc eee eee eee eee e eens 228
Artichoke, Jerusalem....................000- 987 | Bartram oak.......... 2.2.2... eee e eee eee nee 139
ATUM, AITOW...2.. 2.2. eee cece ccc e cece ceecs 114 | Basil. 22.2.2. eee cece cee e cece 244
family. .... 2.2.22... eee e cece cece een e eens 113 108 0: a 245
ATUNCUS.... ccc ccc cece cece eccuceee 175 | Basket oak.............. 2.0. ce cece e cence eee 140
Arundinaria................00. eee ecee ee ees 92 | Basswood ................cceceeeeeeeeee eee es 202
Asarum................220085 wane eeeeenseees 143 | Bastard toad-flax..... 0.0.0.0... cece cee weee 148
Asclepiadaceae...............0.cceeeeee ences 231 | Bay, sweet............c. cece eee ecececececes 161
Asclepias..... cece cece eeceeeeecceeeeeeensenee 231 | Bayberry................c ec ceee cece eee eens 136
0) | 227 family... .... 0.0. e eee e eee cece nec eees 135
Biltmore. .........2202.. 0-2 e ec eee eee eee 227 | Bean, broad............. 22. eee eee ee eee 188
10) E:T) | a 297 hyacinth. ........... bance cece necncccvece 190
de) 6 228 2 006 190
prickly ......2.. 02... e eee eee eee eee 192 | Bear oak. ....... 22. eee eee cece ee ences 140
Te 228 | Beard-tongue.......... 22.2... cece cece eee ees 250
2:5) 192 | Bedstraw............ 22.2 elec eee eee eee 257
white............. 00 cece cece eee eeeeeeeees 227 ON 258
Asiming... 2.2.2.2... ccc ec ce cece ee eeseseeneee 161 1 | 258
ASparagus...........2.. 2022 c cece eee cece 123 Shining. ..... 0.2... cece cece eee cee 258
Aspen, American.............00-0.ccccee eee 134 sweet-scented ..........c.eceeeesceceeeees 258
large-toothed . .......... 2... ces cece ence 134 | Bee mint........ 0... eee eee eee 245
ASPCIUQO. .. 22... ee eee cece cece cece cece ee ees 238 | Beech. ........ 0. cece cece c ee cece eee eee e cece 137
Asperula... 2.2.2... e cece cece eee e ee eeees 257 10) U0 136
Asphodel, false bog................220000ecee 119 family... 22.2.2... cece eee cece cece eneees 137
nn 55, 57, 58 ss 57
Asplonium............2.... cece ce cee cece eee 55-56 | Beechdrops..........2....02cccceeccesccceecs 255
Assimin ......... 202.222 ce cece cece ce eneecuces 161 | Beggar-ticks, swamp...........-..--eeeeeues 289
Assiminier...... 20.0.2... cece cece cece eeeeeee 161 | Bellflower.......... 0... ccc cece cece eee ceee 262
70) :) 279, 282 family... 22.2... lel eee eee cece eee -. 262
blue WOOd....... 22... ccc e cece cece eee eee 280 MAMSN ... 2... e eee eee eee cece e ces eeces 263
CALICO... ceca cece cece cece cece eees 281 | Bellwort..........0 0. ccc cece cece cece cen anes 120
family... 2.0... cece cece cece cece cc ceees 268 | Bent grass............. cece cece cece cece ee aces 83
150) 276 | Benzoin...............0.0 2 cee cee cence eee eeee 261

INDEX. 309

Page Page.

Berberidaceae. ...---..---e cece cece cece e cere 160 | Blue cohosh ..........++- 0-2 eee eee cece eens 161
Berberis.......2.... cece cence eee cee e er eeeecece 160 dogwood... .------- esses cece cece eee e eee 220
Bermuda grass... ..... 2-0-2 ee eee eee eee neers 85 flag... 2... cece eee ee eee eee eee ence ens 126
Betony, Wood .......-..2--.eee cere eee eeeeeee 254 lettuce... 2.2... cece eee ee ee cece ee eee enone 266
Betula. . 1... - ee eee eee eee cece eee eer eeecees 137 PHIOX . 20-22 eee eee eee eee eee eens 235
Betulacease. ....-- cece eee cece eee e ee eneeenes 136 toad-flax... 2... eee eee eee ee eee eee eee 250
Bibliography of District flora......--.------+ 13 VOLVO. 22. e eee eee eee eee eee eee ences 239
Bidens. .....--- cece ence eee cece eee eee eeeeees 288 | Bluebells.......---.----- 020 eee eee eee ee eens 238
Big bluestem......---.----ceeeeeeeeeeeeeeees 72 | Blueberry ....-..-----------e cece eee e eee eees 224
Bignonia.........0222--- eee eee eee eee eens 254 dryland ........0-020 seen eee eee eee eee ee 225
Bignoniacease. ........02ee eee e sees cece eeeeee 254 early highbush............-++---------+++ 225
Bikukulla.... 2.2... ence eee eee ee eee cece eeeee 163 family... 2.2.2.2. 0-- eee eee eee ee eee eee eee 224
Bilderdykia..........0--0-ee eee eee ee ence es 146 highbush.........--+------eeeeeeeeee eee 225
Biltmore ash. ..........--02 eee cece e ewww eeeee 227 | Bluebottle........---..0-- e+e eee eee ee ee ee es 293
Bindweed .......-------eceneeceececceeeeee 147,234 | Bluecurls.......-----------eeeee nsec ee eeee es 241
Birch... 2. cece eee cece nee e ee weet wesc ee eeeees 137 | Blue-eyed grassS........---------eeee eee eeeee 126
plack. ... 2... eee cece eee e cece eee eeeeeee 137 | Bluegrass.......-.--eeeeeee cece eee ce ec eeeees 87
Cherry... 2... eee eee ee eee seen eect eee e ees 137 Canada..........-- cece cece cece cence ceees 88
family .......-..e0ee ee ee eee eee eee ences 136 Kentucky .......002e0- ee ee eee cece eee eeee 88

TOD. occ e cence cence nent e eee een eeneeenes 137 | Blue-hearts...........-22----- eee cece e eee eeee 253
hd) nen 137 | Bluestem, big....-.-..-------+e eee ee eee eeeee 72

a 2) 137 little... 2... ccc eee eee cece eee cece ee eeeee 72
Bird-foot violet. ........--.0e2 ee eee e eee eee ees 908 | Bluets............cecee cece eee e eee e eee eececes 259
Bird’s-foot trefoil. .......-------seeeeeeeeeeee 184 | Boehmeria........-.---22 ee eee eee eee eee neers 143
Birthwort family ............--+-- eseceeecece 143 | Bogs, flora of .....-.....eeeeerr cece eee eeeee ee 20
Bishop-weed, Mock. .........+---e2--ee eens 219 | Bolle’s poplar........------+-+ an eeeeeeeeeees 135
Bitter cress. ... 2.2... - eee eee ee ee ee eee eeeee 169 | Bomeset.......----- se ee cece cece eee cece eees 274
Cock... - ence ee eee eee ee eee cent en eeeees 144 false... cece cece cece cece eee c eee eee e ee eees 275
Bitternut........----. cece e eee eee eee eee eens 136 upland. .......-00s eee eee cece eee ee cece 274
Bittersweet... 2. .---- cece ee eee eee eee eens 199,248 | Boott’s fern... ..-------seeeeeeeeeeee eee eees 58
Black alder.........-- geen eee cceenereeeceeees 199 | Borage..........0ee sence eee e ence eee eee eecee 238
| res 227 family. .... 2.2.22 eee eee eee eee eee ee nees 237
Dirch ....ccceccececcccececcececeececceees 137 | Boraginaceae........-.-----eeeeeeeeeceeecees 237
QTASS. 2. eee eee ence ence een seen eeecees 118 | Borago.........eseee cece eee e ees e eee ee erence 238
GUM... 22 eee eee eee eee cece cere e cece settee 299 | Bostomivy....-.......eeeee eee eee e eee eeeeeee 201
DAW occ cece ccc ceccecececeececeneneenees 261 | Botanical Club of Washington..............- 13
huckleberry ......-----eeeeeee eee eee cece 294 | Botrychium.........----.seeeeeeeeeeeeeeeees 52
JACK. 2.2.2 eee eee e eee eee eee renee ences 139 | Bottle gentian...........- Lene eee ee eeeeeeeees 229
loCUSt .. . eee e eee e cece cence eee eeeeeeeeee 185 | Bottle-brush......-.....---------eeeeee reese 92
MOKIC... 0... eee e ene e ewww cece cece eee eees 183 plantain ...-....... 2... e eee eee eee eee ees 256
Mmustard.........- ee eee e eee eee ewe e ew eeee 170 | Bouncing bet.............2- eee eee eee eee eee 155
| 140 | Boxelder.......-.--....0-2e- ee eee eee eee eee 200
poplar... 22.222. cee ee eee eee cece ee eeeeee 134 | Brachyelytrum............-----------eeeeeee 82
TASPDEITY ..---- eee eee eee eee eee ecto eee 175 | Bracken..........-----2eeee eee e cece eee eesere 54

snakeroot........22ee cence eee eee eeeeceee 156 | Brainerd, Ezra, assistance in determination
SUMAC... 0-2. eee eee ee een cece eee een e eens 198 of Violets... 22... .cc cece eee ence eeeeeeee 206
walnut. .......----- eee cence cece eee eens 135 | Brake. ..... cece cece ence ce ew cere ence es eeees 54
3110), ore 133 | Brasenia.........----02--eeeeeeeeeeeecceeee -- 158
Blackberry lily......-------eeeeeeeeeeceeeees 126 | Brassica..........cececeseeesceeeeee er eeeeees 170
eG en 175 | Brassicaceae.........0..----- see eee eee eeeccee 163
SWAMP. 2... cece cece cence eee eeeeereeceees 175 | Brereton, John A........-.-------eeeeeee cere 13
1 | es 175 | Brittlefern...............-----+- we eaeeeeceee 57
Black-eyed Susan... .....--------eeeeeeeeeee 2296 | Britton violet............--------seeeeeeeeee 208
Bladder campion..........---------eeeseeeee 154 | Britton and Brown’s Illustrated Flora, co-

fT. 2. eee eee eee ee ee eee eee eee e eens 56 ordination of nomenclature with....... 16
Bladdernut......-----.-.ssee cece cece eestor 200 | Broad bean........--.ccceeee eee ences eee eeeee 188
family........------- eens eee erence eee 200 | Brome gTasS.......-.--eseeeeoeeenen ee ssceees 89
Bladderwort......--------sseecece eee eeeeee 255 | BroMUus......sseeeee- cee eeee reece eset eseeeee 89
family........02---- eee ence eee e ence eeee 255 secalinus (illustration).........-------+++ 66
ZIGZAG .. 2. cence ence ec ee eee n reese ceecees 255 | Brooklime, American............-------+se+- 252
Blake, S. F......--------eeeeeeceecceceeceeee 14 | Brookweed.........--.- eee eee e eres nce ceecee 225
Blazing star. .......------eeeeeee eee ceee eee 119,275 | Broom ..........--22-----ee se eeeeeeeeeeereee 183
Blephariglottis. .....--------eeeceeeeeeeec cess 129 SOUZO 0... eee ence eee e eee erence et neeeees 72
Blephilia.....-.0..------ eee eeeeereeeee ences 244 | Broomcorn millet............- wcccnnsccsenace 77
Bloodroot .. 22... eee eee ee eee eee eee eee eeeeee 162 | Broom-rape.......-.----seeeee- ee eecces weeee 205
Blue beech. ........0-0--- cess eee e eee eee. = 136 family.........--- eeeenees ecccccccceeccee 254

310 INDEX.
Page.
Browssonetia... 2.000.000 c cece ce ceeecceccee. 141 JAMALY QTASS. oe ec ee eee eee
Buchnera. 2... 0.0.22. ceeccceeccecc cee on |
Buckthorn family........................... 201 | Cannabis... 2... o.oo eee cececececeee ee.
Buckwheat... 22.0.0... eee cececcccceceeeee 147 vaper family... oe... eee eee ee eee eee
family... 2.2... cce cece cece 144 SPUPge. cece cece cece
Buffalo bur... 2.2.2.2... 0 2c cece cece eee. 248 | Capnoides.... 2.2... ee ecee ec ee ee.
0 184 | Capparidaceae...... 20.0.2... ecee eee.
Bugbane, false..... 2.00.00... 22. cece eee ee 158 | Caprifoliaceae.............00..00-0000
Bugleweed.. 2.2.2... c cc eeeecee cece. 241) Capriola.. 2.0... eee eee cee ceeeeee eee.
Buglewort... 2.0.2.2... cece cece eee ee 246 | Capsella... 2... eee eee eec cece eee.
Bugloss. 2.2.2.0... eee ec eee eee e eee. 239 | Caraway... 2.02... cece cece,
Vipers... eee eee cece cece cece eee 239 | Cardamine....... 0.0.2... eee eeee ee,
ee 97 | Cardinal flower.........................,
Bunch-flower... 0.00... eee cece cece cece. 120 | Cardiospermum.............................
family... 2.22... eee ceccccceeeccecee ee. M9 | Carduus.. 2.2.2... eee cece eee.
Bupleurum.......... 2.20. 2.2..0.c.eeeee eee 215 | Carex... eee eece ec cee cee,
Bur marigold.... 2.20.2... 0.0.0 e cece eee P89) Carica... ee oecceec eee,
ee 140 | Carnation.....20200000.0000.0000 ee.
SMAaKeroot...... 2... eee eee cece 217 | Carolina poplar......................
Burdock..... 222.200.0000 cece cceeececcee. 292 Carpetweed wnececee cece cece cecaceceescucecccee
Burgess, E. S., work upon Aster............. 279 family.... 0.2... c eee eee
Burnet, American........................... 177 CarpinuS...... 2.2... eee cece.
Salad. 2... ee eee ce cee ee eee 17 | Carrion flower.....................0
Er 62 | Carrot... eee
Se 62 | Carum....... ee. eceeeceec
Bursa... 2... eee eee eee ee eee eee 165 COT Yd... eee cece ce cecec eens
Bush Clover. ................cseceeeeceeeee es IST | Cassia...
honeysuckle... se... ee eee eee 250 | Castalia... 2...
Bushy pondweed......... 0.0... .e...ceeeees 84) Castanea... eee ee!
Buttor-and-eggs.. 0.2... eee ee eeeeeeeeees 750 | Catalpa.......ceccccc see
Buttercup..... 0.0... 222. sects eee eee eeeees 198] Catbrier.... oe.
Battery POD eee e reece cette teen eer eeeee mt Catchfly, night-flowering... beceee.
Butterfly Weed csesseeeeeeeeeeeccesseee 22 | Sweet vliam
Butternut... 2.2.0 c ce cecceeceee 135 Cathartolinwm .......6..0.0cccecc 00.
Button snakeroot....................----.... 217 :
Catnip... 0... eee cece cece cece
Buttonbush............ 0.000. ccc ccc cece eee 257
Cat’s-ear... 2. eee eee eee.
Cabbage....... 0.2.2... cececececeeecececceee. 170 :
Catetail. eee.
Skunk... 22. eee e eee cee 114 family
Cabomba.. 2.2... cece ec cccccccece 155 we nna tester st easec sce ces
Cabombaceae.......... 0.02 eeceeeeeee ee, 155 | CUMCAUIB. «one eee eee eee eee eens
Cacalid. 0.0.0 e eevee eeeecccc cc 291 Caulophyllum....................0000.......
Cactaceae... 0... eee eee e cece 211 Ceanothus..........0....0..ccceee cece e seek.
Cactus family....0.. 000... ceccce eee au Ce’ Trrtrtet ete eeses cerns e sees e eee es
Caesalpiniaceae............ 2... ccc ccecee eens 180 OTe nnnerneeseeecec eee ceseces
Calamagrostis............000 000. c cece eee e ee 84 VOSSOF. «eee eee cece eee e teens
Calamintha...........00.0.0000- 00, 244, 245 Celastraceae...... 2.2.0.2... cece eece cece
Calamus... 2.2.2... ccc ec eeceeee cee ccccee ee 114 Celastrus..... 2.2.0.2... cececececececece cece.
Calico aster. ..........ccccececeeeccceeecece.. asi | Celery, Wild. ........... 0... eee
Callitrichaceae...........0.2.0ccccecececeeee. 197 | Celtis... 00.22... eee eee teeeeeceeeeeeee
Callitriche. . 2.02.0... eee ee cecececececee ee. 197 | Cemchrus............. lee.
Calopogon........ccceccccccccceceeecceeee... 130 | Centaurea....... 22... ce eee
Camelina................ccccceceeeeeeeceeees 165 | Centunculus....-.........00.0002000000000...
Camomile, corn............2.-0cecececceeeee. 290 | Century plant...............................
Campanula...... 2.2.0.0... eee ececccece cece. 262 | Cephalanthus...........0.00..0...000000008.
Campanulaceae...........0...0..00.0 0c eee 262 | Cerastium...... 2.0.2... cece cece ee
Campe.... 2.2... ceeeeecececcececcccecceee. 168 | Ceratophyllaceae...............00. cece
Campion, bladder.....................0..... 154 | Ceratophyllum...............00 000. cece cece
SNoWY......-- vec eececececccccccccceccece 154 | Cercis.. 2... 2... eee eee eens
BtAITY eee cc eee eee eee 154 | Chaerophyllum..............................
white... cee eee 154 | Chaetochloa...... 2.0.0... eee eee eee
Camptosorus............ 0.00 c eee ce eee ce ee 55 | Chaffweed............0000 000 c eee cececee eee
Canal, Chesapeake and Ohio, flora of........ 8 | Chain forn.......... 00. eee ccc eee
Canada bluegrass......... 02... ce cececececece 88 | Chamaecrista............. 0... cece ecco cece
re 121 | Chamaelirium.........................0.....
thistle. 2... e cece 292 | Chamaenerion..................00.000. 0-008.

INDEX. 311

Page. Page.

Chamaesyce...........2.0--05 ce ceceseenseeee 195 | Climbing fern................202seeeeeeeceee - 88
Charlock..........20- cece cece ence ceceeeeneee 170 hempweed......sssesecceccecccecenes seen «275
Chase, AgneS..........22..e eee eee eeeneceees 14 TOS@. 2.0 eee cece eee cece eee eee eer eecees 174
Cheat..........0 22 ccc ee eeee eee e eee c cence teens 90 | Clinopodium.............---22.eeeeeeeeeeeeee 244
Checkerberry.........-.-0seseeecececeeeeeeee 222 | Climton’s fern..........0.0seecceeeeeceeeeeees 58
Cheeses......... 00 cece cece eee eee eee e ee erecee 203 | Clitoria............. dene cen e ee enceeereceeeeee 189
Cheilanthes...........2..220ee- eee ween ener ee 55 | Closed gentian................ccceeeeeeeeeee 229
Cheirinia.........2. 2. eee eee eee eee ee eee 167 | Clover... 2.2... cece ee eee eee cece eee teen eneee 183
Chelidonium..........-.-------. sees eeeeeeeee 162 alsike... 2.2... cece cece eee eee cece eeeeeee 184
C0 01 :) (0) 1X: 250 buffalo. . 22.2.2... eee ee ee ee eee rere eee 184
Chenopodiacese............... cee eee eee eeeees 147 10) 0 :) «nn 187
Chenopodium... .........0---2 cee eeeeeeeeeees 147 CTIMSON . 2... eee eee ee eee cence eee eeeee 184
Cherry birch........-.....-0see sence cere ences 137 110) ns 184
Choke...... 22... eee cence eee cee eeeces 180 A) 01:0 0 187
BTOUNG........0--- ee eee e cece eee e recone 247 rabbit-foot ..........-- 2. eee cece ee eee eee 184
Jerusalem. ........----- eee cece e eee en eee 247 56 ne 184
SOUL... 0c cece eee cece eee ee eee eee en eneee 180 a) 183
a) 180 White. ....... 0... e eee e eee cece eee eeeaee 184
wild black............20.ceeceee eee ee eeee 180 | Club rush, river..........------e-ee eee eee es 97
Chervil.... 0.0.0.2 eee ee eee cece eee eeeee eeeeeee 918 | Club-moSs..........------ eee scene cetenereee 59
CHOSS... oe cece ee ec eens ete cece eee eeeeeneeenes 90 family... 22.022. c eee eee cee e eee e eens noes 50
Chestnut. .......00. 2c eee cece cence ce eeeereces 187 | Cnicus.....2...- 22 cece eee eee e eee eee enceee 292
HOTS... 2. eee wee cece eee eee eens eeeees 200 | Coastal Plain, geology of.................006- 17
OAK... eee eee eee eee eee cnet te eeeeeenes 140 sity: 0) 17
Chickasaw plum..........---..--+--seeeeeee- 180 | Cocklebur..............2 cee cece eee e eee e enone 267
Chicken grape............02-0+-- eee cece eee 202 SPINY... 0... cece sec e eee ence cece eee eeeees 267
Chickering, J. W....----.-seeeeceeeee ce eeeee 13 | Cockspur.............eee cece eee cece eee e eens 80, 179
Chickweed...........0cecee eee cence ee ee cere 152 | Cohosh, blue. ........... csc eee scene eee eeeee 161
COMMON... 2. ee eee ee eee cence ee eeee 152 | Colic-root.........2- eee ee eee ee eee eee ee tees 122
family.......----- 22 ee cece eee cece cece 151 | Collinsonia..........c.e cece eee eee e cece eens 246
forked .... 2... cece ee eee eee ee eee weer eres 151 | Columbine. .............ceeeeee cere cece cence 157
MOUS@-CAL. 1. eee eee eee eee eee eee 152 | Comandra.........----. eee e eee e cee eeeceeeee 148
nodding............2.eeceee eee cece eens 152 | Comfrey............ 2. eee eee eee e eee e new eenee 238
Chickweed, star....-......2.0.eeeee ence eee 152 Wild... ccc cee eee eee eee cee cence eee .. 237
Chicory..........0cece cece eee e ee eeeeeereceeee 264 | Commelina..........2.2..eeee eee e cece eee cees 116
family... 22.2... ..e eee ence eee eee ence eee 263 | Commelinaceae............ eee ee cee eeeeeceeee 115
Chimaphila..............0...00- 20+ seeeeeees 221 | Compositae......-..2..22- 22 cence eee e een e ees 268
Chinquapin...... cence eee c asec ecaseeeteeeeee 137 | Comptonia............-.-- ee ee eee ee eee eee 135
Chionanthus.............0-- eee cece eee wees 228 | Cone-flower, Orange.........-0+.eeeee eee eee 286
Choke cherry.........-----0cece cece eee renee 180 tall... 2. cece eee e eee eee e eee eet e neces 286
Chokeberry......--.-.-22:-eeee eee eee neces _.. 178 | Conium. ...........2. 2. eee eee ee eee eee 219
Chondrilla........-......0-020- seen weceeeeee 265 | Conoclinium.........-0.-- 20 cece eee erence 275
Christmas fern..........-0...0-+-e-e eee eee eee 55 | Conopholis.........-. 2.222... eeeeeececeeecee 255
BTCON. 2... eee e eee eee eee eee ee eet een e nes 59 | Conringia............-2.-- eee e eee e econ cence 167
Chrosperma.........-----02 eee sence ee ee eee 120 | Contributors to Flora of District of Columbia 14,15
Chrysanthemum.........-..-----sseeeseeeeee 200 | Convallaria...........0--2 ee eee eee e eee eee 123
Chrysogonum . ........-.--. cess ee ee eee recone 285 | Convallariaceae............0--e eee e cece eeeee 123
Chrysopsis.........-..eceseeeeee eer eeeees .- 276 | Convolvulaceae..........----2 eee eee eee ee ee ee 233
Chrysosplenium ..........-...----+--e- sees 171 | Convolvulus.............0-0- ee eee eee eceeeeee 234
Cicely, sweet... .....2...-0- eee eee cece renee w. «218 | Coralberry............----e-ee eee eee eee ...- 260
Cichoriacese.... 2.2... .ce cece cece cece ee ceees 963 | Corallorhiza...........0-0.. cence eee eee enone 131
Cichorium..........-0..-0-ese cece cece cence 264 | Coral-root........ cece e eee eee ene cee eeceeeee 131
Cicuta.. 0.0.02... e eee ce eect ee cece ee ences 919 | Cord-grass...........ee eee eee ee eee eee neers 85
Cimicifuga........-. 20-0. cence eee reece ces 156 | Coreopsis..........----eeeeeeceee rece ces ees 288, 289
C0; 000 oC: F< U0) os es 66
Cinnamon fern........--....-2-0:eeee eee eee 53 camomile..............cceeeeeneeeeceeeee 290
Circaea..... 2. cee eee eee eee eee cere eeeeer 213 COCKE. 2... eee eee cence cece e ee eeeees 153
Cirsium... 2... 2... eee eee eee eee ee eee eee 292 gromwell.......----2..-0- 0: eee e ee eee eee 238
Cistaceae. 0.02.20. eee ee eee eee eee eee eens 205 Ts 261
Citronella..........--2-.. 0 eee eee eee ener eres 246 speedwell...........-. 22. cece eee eeeeeeee 253
Claytonia..... 2.20.0. - ee cee eee reese rere eenee 150 squirrel... 2.20.2... cece cece eee ee ee enee 163
Clematis............ 02. eee cece cece eee eee eeee 160 | Cormaceaé..... 22... eee cee eee e eee eee e ee ences 219
Cleome..........--- see eee ete eee e eee eeeeee 170 | Corn-flower.............ceee cece eee e ee eeeeeee 293
Clethra........-.------- ee eee eee ee cece eee eee 220 | CormuS........ 2. eee ee eee eee ee eee cece ee eeeee 220
Clethraceae.........-...-------e eee eee eee eee 220 | Corrigiolaceae........2....cee nese cece essen 150
Cliff-brake..........-.00e-e ee eee eee ee certs 55 | Cortaderia...... 2.22... ees cece wee ec eee eee eee 66

312 INDEX.
Page. Page.
Corydalis... ......22. 2.2. cec ccc cece eee ceucee 163 | Cynodon.... 2... eee cece ccc cecccceeeuees 85
Corylus.... 2.0.0... cece cece eee eeececcccccces 137 | Cynoglossum..............00ccceeecccececece 237
Costmary... 2.20... cece eee ce nec eeeecce scence 200 | Cymorylum... 2... ccc cece c cece ccc cccceceeces 220
Cotinus..... 22.0.2... 000 cece cece cece cen ceece 198 | Cynthia. 2... cece cc cee cece eee 264
Cotton grass.........02.. cc ceeecccccecececee 98 | Cyperaceae.... 2.2.0... c eee cee cccccccccccee 92
upland..............2... nee e eee eeneeeees 204 | Cyperus... 2.2... ec c cece ccc ceeeecccce 93
Cottonwood... 2.2.2... eee cece ccc ce cecce 134 | Cypress, bald......................000----- 5. 61
Couch grass. - 2.2.0.0... 2. cee eec cece ccc cees 90 SPUTQC. 2... eee c ce ee ence een anes 197
Coville, Frederick V.....................0... 14 VIMG. 22. cece eee eee ceeeceeecace 233
Cow parsnip..... 2.22.2... ccc ce eee eee eec cece 218 | Cypripedium..........00... 0... cece cece eee 128
POA... eee cece eee eee cece cece c ec eece 190 | Cystopteris... 2.0... cece cece cece 57
Cowbane............ 0. cece ccc cece cccceceecce 218 | Cytisus......... 000 cece ec ccce nc cecccuececee 183
Cowherb. ..... 2.02... ccc cece cece cee ceceeccee 155 | Dactylis...... 2.0.0... ccc cee ce ccc ccecee 87
Cowslip, Virginia.........2.00..0..0...0.0000. 238 | Daffodil...... 0.0... ccc cece cee e ee 125
Cow-wheat........00. 2... ceccccceecccccecece 254 | Daisy fleabane...............0000. 0. cece eee 283
Crab apple, American....................... 177 OX-OYO... eee ee cence e een ccccecace 290
Siberian... 2... 0.0.00. e cee 177 | Dame’s rocket........ 2.0... cece ccc cece cence 167
Soulard. . 2.2.2.2... cee cece ccc ce eee cee 177 | Dandelion, common.....................0... 265
Crabgrass..... 0.2.00 cece cece eee ccc cc cece cee 73 fall... 2. eee cc cece eee eceneeeeee 264
CraCea... 22... cece eee cece eee e ccc cecceceneee 184 Ted-seeded....... 22... cece eceeecccee cece 265
Crack willow... 2.2.2... .cccccccceccececceeee 133 | Dangleberry............... 0c. cc ccc ccce cece ee 224
Cranberry, highbush........................ 260 | Danthonia............ 0... elec cece ceeee 85
Crandall, E. Le... 2. eee ccc ce eee eee 16 | Daphnaceae............ 2. ccc ece ccc ccc cee eee 211
Crane-fly orchis...............0..0...0....-.- 132 | Dasystoma.... 2.2... ec cece ccc cece cece ccnc cee 253
Crane’s-bill............00 02. cece cece cece eee 190 | Datura....... 2... eee ecu e ccc cee eee 247
Crassulaceae........ 0.0.2... ccc ece cee ececccee 171 | Daucus............. cece ccc ccc cceeccucceecs 217
Crataegus... 2... cece cece eee ccc ccc ceee 178 | Day flower............ ccc cece c cee cececceee 116
Cream violet... 2.2.0.2... eee cece cece cece 208 0 122
Creeping thyme............2.0..0........... 245 | Dead nettle............. 0. cece cee cece cece ees 243
LO) 0) ce 267 | Deciduous holly............. 0. cece cece eceee 199
Cress, bitter. ....... 2.2... cece cece cece cece 169 | Decodon.............. cc. cece eeeecccccecceece 212
lake. 2.2... e cece cece cece cece ccee cece 166 | Deerberry......... 2... ccc ccc ccccceecceuce 224
MOUSC-€8P . 0.2... eee eee ence eee c cece 168 | Delphinium.............. 00... c cece cece eee 157
PONNY.. 22. eee ee cece cece cece ence 167 | Dennstedtia............ 0... e cee ce eee eceese 54
1) 168 | Dentaria... 2.2.2... cece ccc cece eee 169
Winter... 20.0... cece cece ence cee ceee 168 | Deptford pink..............02 2. cece eee eee 154
yellow... 2... eee e ccc ce cence cece 165 | Deringa.............. 0. cece eee e cece nee cccee 218
Crested iris... 2.2... 0.0... cccccccececcccecee. 126 | Deschampsia............... 00.0... ccce ec eeee 84
Crimson clover.............---c-cececee-e ee 184 | Desmodium... ... 2.22... ccce cece cee eceeeees 186, 187
Crocanthemum,.......22000.ecceeeccccceccene 205 | Devil’s-bit......... 00... c cele cece ccc cn eee 119
Crocus. ..........002. cece eceeecccenccccccuece 126 | Dewberry.......... 02... ceeec eee eeee eens 175
Crosswort . 2.2... 2. cecec ce ccec cee cceceucceeee 296 | Dianthera....... 2... cece cece ence cece 256
Crotalaria. . 0.0.0.0... 0. cece eee cee ccc c cues 183 | Dianthus............... 0.0. c cece cece ecee 154
Crotonopsis...............ccccecscccccucccuce 195 | Dicentra..........ccceceeeeccc eens eee eeceeees 163
Crowfoot family. ..... 2.00... cece eee c eee 156 | Dichanthelium, subgenus.................... 75
Crownbeard, yellow.................eeceeeee 288 | Dichrophyllum....................00.2eeeeee 196
Cryptotaonia..... 2.2... ..cccccesceeceeneecee 218 | Dicksonia.............. 2.22 e cece cee ce eee 54
Cubelium...........00...ccce ee eeece eee ccueee 206 | Digitaria. ... 2.2.2... ccc eee e eee e cece eeeenes 73
Cucumber, Indian.................0..cceeeee 124 | Diodia.... 2.2... cece cece cece ceeccees 258
bo) 124 | Dfoscorea..... 2.2.2... cece cece ee lececeecees 125
A es 262 | Dioscoreaceae..........ccccccececcecccceccucs 125
6 Ce cs 262 | Diospyraceac.............cccece cece ceeccecce 227
Cucurbitaceae....... 2.2 ee cece cccceeccceccece 262 | Diospyros............ 0. cece eee ence eee cee 227
Cudweed, low. .... 2.2... ccc eeecececcccceccee 284 | Diplachne... 20... 00.0. cc cece eens een eucceuce 85
purplish... 2.0... 0... cece cece eee eee cence 284 | Diplopappus..........cccceccceeeencecccecce 282
Culver’s-root. . 2.0... cece cece cee cecceeeee 253 | Dipsacaceac...........0.. cee eccceecceecceucs 262
Cunila.............. wet eee eens ee ewer eeeeaes 245 | DipsacuS..........0.....cceeeceeccccsceceecs 262
Oe 212 | Dire@........... cece eee cc nec cececceecceecces 211
Curled mallow..............cccccccceeencceee 208 | Discopleura..........0ccccc cece eee ecceucccce 219
Curly-grass family...........00....cccceeeaee 53 | Ditch stonecrop...............ceeceeceeccees 171
Currant, red..... 2... 2. cece eee cce eee ee ences 172 stonecrop family..............-eececeeces 171
Wild black..............0cscceeeeseseeeee 172 | Dittany.............2....0.0. seneeeecececees 245
Cuscuta............cc..ceee eee a veeeeenenenee 234 | Dock.............0.. cece encccccceacececnecce 144
Cuscutaceas...... 0.00... cece ec eeeeneeeece . 234 Ditter... 0. eee eee cece cence eee 144
Custard apple family.................cceceee 161 TAITOW . 22.2 cece eee eee ec ceeeeee 145
Cut-grass, rico........... ceseneees aeeeee eesee = 81 SWAMP... 2... eee eee e eee e ence eceeeee 144

INDEX. 313

Page Page.
Dodder............. cece cece cece eee cece ees 234 | Elm family............. cece eee eee een eeees 140
family..... 0... cece eee eee eee eee eee 234 6 141
SiC) (6 234 | Eloded..... ol. cece eee c eee e eee een eeenenes 66, 205
hazel ... 0.2.2... ce eee cee eee eee ee eee cece 235 | Elymus................0... 202 ce cece ee ee eee 91
SMAI weed ...... 0... cece cece ec ececeeece 235 | Empress tree.............. 02 eee eee ence eens 250
Dodecatheon. ...............02. 2. cee e eee eeee 227 | Enchanter’s nightshade....................- 213
Doellingeria...........02.ceeeceeeeeeeeeeeeee 282 | English elm......0. 0.02... eee eee e eee eee 141
Dog fennel............000cccceeeeeeeeeeeeees 290 6 Coe 215
TOSG oo oven ccne cc cee cence cence ccncccccccee 174 Plantain......... ccc cece cece cece eee eee 257
Violet.......0.cccceeeesccccccccensceeeees 208 ViOlOt.... 2.2... eee ee eee eee ee ee eee eer eees 208
Dogbane.....2.0..2.ssceseeecececeececcecees 930 walnut one e base ce cnn n ene ccncnccenceeceees 135
family........2..022c-2eeeceeeeeeeeeeeeee 929 Enslenia cence eee e eee n sere eens ceeesseseeneccs 231
Epigaea........ 2.2. eee eee eee cee eee eee 222
Dog-tooth violet.............. eee eee eee eee 122 Epilobi
CPUODIUM, 22... 2. eee eee eee eee eee ee eee eee 213
Dogwood... 2.2... cece cece eee c cece eee ceeeeeee 220 Epipacti8..-----oeeccosecceecccccceceeeeece 130, 131
DIWC....0 0. se eee reese eee eee er eee eee ee ees 220 | Epiphagus.......2..2-02c00-2eceeceeeceeeeeee 255
family PTTTTTISTTTTITITi TTT TTT 219 E quisetaceae c wawacewececccavaccreuanceceeeee 58
flowering eee ee ee ee ee 220 E quisetum wee e cece cnc ceccunncccccececceunece 58
Dolicholus...........-2.220--.222eeeeeee eee ee 190 | Eragrostis...........2.000cceeceeceeceeeeeeee 86
DolichoS...... 0.0. cceeec cece cece cececcewenere 190 | Erechtites................ccce cece eee ee eeeee 291
Downy violet................- eee cece cece eens 210 | Erianthus..................... wececeeececece 71
BD: | 0): 165 | Ericaceae.............. eee eee eee ween cece 222
Dracocephalum...............0eeceeeeeeeeees 243 | Erigenia............. cece eee eee eee ee eee e eens 219
Dragon, gTe@en.......-...22.cee eee e eee eeeeees 113 | Erigeron ............ 0. eee eee eee een cee eee 282, 283
Drop-seed graSS......--seeeecececcccecccccces 83 | Eriocaulaceae.......-...2-2---2.eeeeeeeee eee 115
DY OSCT Ae one oon nnncnnccnnccncccucccuceccecceue 170 | Eriocaulon............cce cc ccee eee cece eens 115
DYIOSCFACCRC.. «oe eccccccccccccecccecccecccece 170 Eriophorum peewee necator resents cenersecneess 98
Dryland blueberry..............0.ceeeeeeeee 905 | ErOdiUM........-+eseeseeeeseee esses eee en ees 190
Dryopteris..........-ceeeeeeeceececeeceeeees 57-59 | E ryngium ween ences cease ease sees sew e nea ee ee 217
Duchesnea.............. ee cece eee eee eee eee eee 175 ETySiMUM. ..-.--++--2e +e sere eee eeee eee eeees 167
Duckweed.....ccccceccccaceccccecececcececs 114 Erythronium epee eeerrreenessesesass wee ee eeee 122
family..........2-eeeeeececeecececeeceees 14 | E scalloniaceae..........ceeceececeeeeccneee « 172
Dulichtum......-.-ceccccccceccccecceccceccecs 95 Eubotrys ate n cence eee enenesenanteccceeseccnes 223
DUITA. occ ccc ccc cccecccnccccucceccceeceeees 72 Fulalia........--000.. 22 essence ee ceeeeeeeeee 66, 71
Dutchman’s breeches.........2000seeeeeeeees 163 | EVOnyMUS.......-.+e0eeeeeeeeeeeeeees es ee es 199
Dwarf goat’s-beard ...........0.eeeeeeeeeeeee 964 | Eupatorium.........+.seseeeeeeee eee eee es a 273
huckleberry .........0.-+-ceeeeeeeeeeeees 294 Euphorbia ................-..202---00- 195,196,197
larkspUr........ssseeeeeeeeeeeeeeeeeeeees 157 | Euphorbiaceae. .........-0000.-----.---00e- 194
prairie WilloW.....2..sseceeceeceeceeeeee 134 European VOTVAIN .. 2... eee eee e wees cece ees 239
spleenwort........s-ssceeceeeeececeeeees 56 Euthamia veteeeseseeeeerereeeeeseeeeeeeeees 278
BUMAC... -----cencccccccececccecccceccece 19g | Evening primrose.............----2------+-- 214
Dyeweed....2.0..2.cccecececceceecececeeeee 183 primrose family................-.---.--- 212
Early goldenrod.............2....22220ee000- 278 Everlasting. ............00ecceceseeeeeeeeee 283, 284
Ot 85 POD-.-- 222s seer cere eceseee cece scer scenes 189
Ebony spleenwort...... cece cece se ceeeeteeees 56 Fabaceae. ....--.--++-+-s0eeeeeeeeeeeeeee sees 181
Echinochloa...........-20ceeseeeeeesecereess GQ | Fagacene......-----+e0-eeseeeeeeeerercereee 137
Eichinocystis... 2... 0cccccecccccecescccceeesee 262 |- Fagopyrum........0--0seeoeeeeeeseeeeeeeees 147
Echinodorus............cccccccceeseeeeeeeee 64 | FAGUS....-----eeerere reer seer ec eee ee ec essere 137
Echinospermum cc eceuuacacucuceceteccsucece 937 Falcata.........cce cece eee eee e cece neceeeees 189
Echium.......ccccccccccccccceccececccuceees 239 | Fall Gandelion........... cece see wec cece enes 264
Eclipta.......cseceeccecceceeceeceeccuceeees 96 | False bog asphodel..........----.-.-..-++.++ 119
boneset........---.2----- eee eee eee eee 275
Hel-grasS. 2.2.0.2. eee eee cee cee cece eee een eee 66
family...........0- 222 e eee eee eee eee eens 66 bugbane..........+----2++-0eeeeeeee eee 158
Eggleston, W. W...--.-..-0.--. cece s eee e eee 14 flaX.-.... 2-22 2e ee sere sees ee eens eee ceeees 165
Egegplant...........2.22222 cece cece ee en eens 247 fOXB]OVO...--2-+e----enener een eeeeeeeees 256
Elatinaceae.......-..-2-- 2-02 eee eee eee ew eeeee 205 GTOMWEll. .....----- 2-22 2eeeerereneeeeee 238
Elatine.......0.0.0+cececececececececececeees 205 hellebore.....-.+++-++++++++++eeeeeeeee es 120
Elder. ........ccccececececeeeecceceeseceecees 261 INdigO.....-2-2eeeeereeeeceeeec sree escees 5
Elecampane..........-.---ee-ceeceeseeseees - 284 IPOCAG. ..--eeererereernrersnccernccoe rene 1
MaAllOW......0eeeseeecee cee ee cece ee eecnes 203
Eleocharis. ............0-02202 eee cece eeeeeeee 95 198
Elephantopus...........00seeceeeeeceeeeeeee 273 Mermaid. ......csceeeeceeeeeeceececeecee Ma
Elephant’s-foot........0000--00- veceecceeeces 273 Nettle....... ce eeeeeeeereeee eres cee eeeeee
Eleusine necpecccacccccccucavevecccccesteteses 85 pennyr ‘oyal. Peessaasocccssoresscerereescns 241
Ellisia. .. 0.2.2 ceca ccccccncccccccccccccccccces 236 pimpernel secscetscossedsoveberte evequtee 251
EIM......cccccccecscecececesecceecesececs _.. 140 Solomon’s-seal............. sonscbeccddevd 123
American.......... caceeneeee weceeecees 141 StrAWDOITY -.---+--seerreseeresrenereres 175
English.........--+0++ vencceccece vececcee 14) | Famejflower.......--0ceseseeeesecees eacceeee 150

314 INDEX.

Page. Page.

Pedia.. 2... ccc ccc cece ccc cece ccecee 261,262 | Flowering wintergreen............. weecceese 194
DS 0, 215 | Flower-of-an-hour............. eeeeee eeeveeee 208
CC ce 290 | Fly poison.................... eeccscccccseee 120
Fern, beech... 2.2.22... .0....ccccceeceeceees 57 | Foeniculum............... we eeeeeennee cesses 215
Dladder...... 0.0.0... eee cece cece ccc ccee 56 | Foreman, E......... scence enececccnecnecene. 18
Boott’s.........0....000 0000.00 20 Nes seeee 58 | Forget-me-not................... weenee aeeeee 238
brittle... 22... ce cece cecaeee 57 | Forked chickweed............. eeseee eceseeee 151
Chain... 2... ccce ence cece 54,55 | Forsythia..................... wee ececeesceee 227
Christmas. . 2.2.2.2... 0c cece cece ceeeuee 55 | Fountain grass... 2... 22.22... .cccceeee ee eens. 66
CINNAMON, .. 2.2.2.0... eee eee cece 53 | Four-o’clock family.................ccccee00. 149
limbing.........00000 0.00.02. Seneceeeees 53 | Fox grape.............. wee ee eeeseeeneeeenes 202
Clinton’s.. 22.2... 0. eee cece ccc cee 58 | Foxglove, false... . 2.2... cccceccccccecceccees 253
family... . 2... eee cece cece cece 53 purple......... 0... ccc ce ceecnnccccce 253
Goldie’s. 0.2... cece eee ce ccc ceccceece 58 | Foxtail, green. . 22.20.00... ee cee ccee eens eee .: 80
STADE. cee cece eee ec cee 52 0) 80
hay-scented .. 22.2... 2... cece cece cee O4 | Fragaria.... 2.2.0... ec cee cece eee vee eeeeeee 175
lady... ...... wane nec e cnn n ee ceneenece - 56 | Fragrant ladies’-tresses...............-.... - 131
MAaMSh... 2... eee eee eee ee eeeeeee 58 SUMAC... 2. e cence 199
Massachusetts... .. 2.2.0... ...ccccceceeeee 58 | Fraxinus.............ccccccccccccccccccceeee 227
New York............ccccccececccccecece 57 | Freesia. 2.2... 00... ccc cceccececcceccceceees 126
OStrich. 2 oo... eee ee cece ec eeece 54 | French vetch....... 0... ..ccccceccccceceeceee 188
resurrection. ........... ccc elec cece eee eee 56 | Fringed loosestrife...............ccccccceee-. 226
TOYAL. 2.2... eee ccceceeecceecececcccceee 52 0) 129
SOMSItLVO... eee cece cece ee ees 54 | Fringetree... 2.2... cece cee ceececeeeeee 228
SWC... eee ee eccccceneneeeee 185 | Frost grape.............. ccc cceecceccecceeces 202
walking. 2.2.2... 2. ccc cece cc cce cece ccc eee 55 | Frostweed............cccecccecceecccece eoees 205
wood......... obec ee eeeeenceeccncccscence 58 | Fuirena........, weneee nn |.)
F@SCUC BTASS. ose cece cee cncncceece --- 89 | Fumaria.................. wen cececcneeece ee. 168
meadow...... ance e ceca ce ceencnsnscccenen 89 | Fumariaceae. ..............0.0065 secsececee. 163

Ls 89 | Fumitory............... asec ceenencee eeeseee 168
SL 89 family... 2... 2. loo e ec ccccccceee sues 168
Festuca. 2.0.2... cee cece cc ceeccccceeee 80 | Galactia... lec cccccecececececcs 189
Feverfew. ... 2.0.0... 2. cc ccceceecccccceeeccce 200 | Galinsoga............c.c cece cee ecececccceece 289
Ficaria.... 2.2.0... ccc cccececcccccceccccccce 159 | Galium.......... 0.2. c cece ecccceceecccees eeee 257
FICUS... 2.2... cece ccc cece cee eeccccccccees 141 | Gama grass... 20.22... 0. ee ceccceceeceeeeceee 71
Field dodder..... 2.0.0... eee c cece cee ceceee 234 | Garden balm.................... wee e eee eeee 244
madder.... 2... eee cccccceeeee 257 phlox...... wee cece cece cece ee weencncees 235
PANSY... ee eee eee cece ee eee 208 | Garlic, European.......................... . 121
a ae 141 meadow.............. once seen ecenccencs 121
Figwort............222.00. pancnccccseeseecns 250 Mustard... 2... 2... ce ee cece ence eee e cece 167
family... 2.2... cccecececcceee 248 2 121
ee 283 | Gaultheria.. 22.2... c cece ccc e eee 222
US 56-57 | Gara... 22... cece ccc eecc ccc cececcccccceces 213
Fimbristylis.... 2.00.0... ccc e cece cece eee 96 | Gaylussacia. . 2.2.2.0... eee ec cece ececceee ee 224
Pir, Scotch... 2.22.22... ccc ccc e cece eee cceee 61 | Gemmingia............ 0c e cece eee ee 126
Fireweed... 2.2.2... ce cece ecccceecce ee 29L | Genista.... 2... 0... cece ee cece ecceccceeee 183
purple... 2.2.00... cece ce eeeeeceuccecceee 213 | Gentian. ...... 2... cccece eee ee -. 229
Pissipes. o.oo... eee cece cece ccceeeccccccccee 128 bottle. 0. cece cece cece ee 229
Five-finger. 22.2... .....c cece cececccedeccee ee 176 CloSOd kee eee eee cece nce ccccnece 229
Flag, blue... 2.2... 20... cece eeccceccceeeess 126 family... 2.2.0... e cee ccccc eee cceeee 228
SWOCE.. cece eee c cee c scence 114 0) 260
A 126 striped... cece cece eee es 229
Flag-root......... 2.00 cece eescecccceccccccee 114} Gentiana... 22.2... 220 eee cc ce eee eee 229
eC) 192 | Gentianaceae........... 22 ..cccecececeeceeeee 228
false... 0... ccc e le cee cece ccceecceeacece 165 | Geology of the District of Columbia. ........ 16
family... 2... cece cce cece eee ce eee 192 | Geraniaceac..........2 2... eeceeccccceeeeeee 190
Fleabane... 2.0.0... ccc cecccccceececcccecee 282 | Geranium................ ote een eeccceneeees 190
Waisy. eee ence ec ccece 283 family... 2.2... eee e ce cccccc cece eens 190
Marsh... eee cee ec cence cc ene 283 | Gerardia... 2.2.2... ooo ccc ccc ccccecccccccee 253, 254
Ploerkea.... 2.0.00... eee e cece cece ecceee ee --- 198 | Germander speedwell.......................- 252
‘Flora of District of Columbia, scope of....... 1S | Geum.... 22... eee cece cece cece cece 175
Florida lettuce. . 2.2.00... ce ene ee eee 266 | Giant hyssop............. 00 cece ce cecececec ee 242
Flowering dogwood. ..................-..... 220 | Gifola...... 2.2... cee e eee eee sete eceseees 283
forn family... 22... 0... eee ee ccc eee eee 52 | Gillenia... 0.2... cece cece cee cecc eee 175
TASPDEITY... ee eee eee cece cece 175 | Ginger, wild.... 2.2.0.0... cc cece cece cece eee 143
SPULQC.... eee eee eee cece eee 197 | Ginseng............ 0. cele cece ccc ee cece ceee. 215

Ginseng family .....................20-2-0---
Gladiolus........... cece cececenccececeserecee
Glecom@.........2-0-2 scene cece cece eee eeeees
Gleditsia...........-0-2- 2c eee eee ee eens

GoOat’S-TUC.. 0... eee eee ee ee ee teen eee
Golden aster.............2---2-2 eee eee seeeeee

GOOdyeTa . 2. eee ee ee eee eee eee eee
Goosefoot family...............--2---0ee-0--

Nettle-leaf. .. 2.2.22. eee e eee eee eee
GOOS@ STASS. 2... eee eee eee eee eee eee
Gooseberry family......-.-. voce cece eee eeee

Goose-grass. .... seeeeeee cnet cece cece ee eeeeeee
Gourd family.......--.--..--0---200-eeeeeeee

flower, structure of. ..................-..
fountain...............220.0. 2. eee eee eee

orchard.............- 22-2 cece eee eee eeee
perennialrye...........-.....---..----.-

INDEX. 315
. - Page.
215 | Grass, poverty...........---.- 0. eee ee eee eee 82
126 quack ...... eee eee ee eee eee eee eee 90
243 QUICK... 0. eee eee eee cee eeee 90
180 quitch.. 2.0... cece eee eee eee eee ee eee 90
88, 89 rattlesnake. ....-....2-. 2. -e scence eee eee 89
189 redhead .......--2---. 2c eee c ee eee eee eeae 63
284 reed Canary.......--------- 2-2 ee eee eens 81
175 TOSCUC. 2.2... ee ee eect eee neces 90
264 Fg .0) 010) 81
184 rough-stalked meadow........-...-.-...- 88
276 es 90
297 squirrel tail. .........-.....0. 26. eee e eee 91
114 stink. 2.2... 2.2. eee ee eee eee eee eee ee eee 86
286 sweet vermal............. cee eee eee eee 81
991 tall oat. ... 2. ee ee cee eee wees 85
285 1 Ce) 9 (: 84
276 velvet ...... cc. eee eee eee ec eee ee eneee 84
278 wheat..........- 22 eee eee ence nee e eee 90
278 White... . 2... eee cee eee eee eee neces 81
278 whitlow we cence ee eee ec eee e teat ec eeeenees 165
278 wire wee eee e eee cece eee ence eee eee e eens 82
58 Witch... 2.2. ccc eee ee eee eee eee ee 77
00) 98

231
31 yellow-eyed ......-.-.- ee ee eee eee e eee 116
147 Grass-pink. .........--2- 0. eee e eee ee eee ences 130
148 Gratiola..... 2.2... . eee eee eee eee eee ee eens 251
85 Gray polypody........--... ec eee cee eee eens 56
172 poplar..........-2 0 eee eee ee eee eee eee 135

Gray’s Manual, coordination of nomenclature

172 With.o..000c.ccececececececececeeseees 16
258 Great lobelia. .. 22-2... 222. eee eee cece eee 263

262
TAG WCE... 6.2 eee ee ee eee eee ee eens -268
204 Great Falls region, flora of................-.. 19
202 Green ash........-...-+ cece cece eeeeee ceeeeee 228
202 Aragon... 2... ee eee eee eee eee 113
201 Coxtail........00cccecececececeeeceueceeee 80
62 violet.........02.00e00-e0eee veceuececeuee 206
202 | Greenbrier........2.2-e.e-2-eceeeeeceeeees 124, 125
202 | Green-flowered milkweed................000: 231
122 | Grindelia.........-.---2-+-02seeeeeeceee eee 1 275
202 Gromwell, Corn.....-.-...-..2 2c eee cece eee 238
202 1: : 238
90 | Grossularia........... voce cececececessceueuas 172
91 | Grossulariaceae........... ve cececececeeneneee 172
80 | Ground cherry..... vaca cecnceceeeeececeeeees 247
83 AVY oo cece cece cece cece ces eeeeeeesecennees 243
85 0: 59
118 OC 235
126 | Goundnut.......... 0.0... 22 eee eee eee eee 215
89 | Groundsel bush. ...........-...-222--22 22 eee 283
81 | Gum, black.............. 22220220 eee ee eee 220
98 Rs) 173
90 | Gum-plant...............20 eee eee eee eee 275
83 | Gymnadeniopsis............2220008 Leeeeeeeee 129
66 | Gymnopogon........2.. 2... cece ee eee eee eee 85
89 | Gymnostichum...........-----20e eens ee ee eee 92
66 | Gyrostachys.......-....0-2-0e eee e eee e ee eens 130, 131
66 | Habenaria...........-.------ 2-22 e eee eee eee 129
71 | Hackberry. ...........----. 02 eee ee eee eee eee 141
85 | Hair grass............2202 2 cece e eee ee eee eee 82
82 | Hairy bedstraw. ...........---0- see cece cece 258
72 hawkweed .........-..ee sec e eee eee eeeee 267
81 A020) | 189
94 | Hallock, L. V....-.....----- eee eee eee e eee 16
87 | Haloragidaceae............----------- eee eee 214
90 | Hamamelidaceae..............-------eeeeee- 172

316

Hawkbit, common...................22.-20-
Hawkweed, hairy....................22.000-

Hay-scented fern............... cece cece cece
Hazel dodder...... wee cece eee c ee ence ee enaee
Hazelnut.............0. 200 c eee eee cee cece

Hedge hyssop...... 2... cece cece cece ce cece eee
Mustard........ 0.00.2 cc cece cece ence cece

Hemicarpha............. 0.000. 0 cece cece cence
Hemlock. ........0... 00000 c eee e cece cena cee

Henbit.. 2.2... cece cece eee e ee

Herbarium, District Flora.................0-
Hercules’ club.... 222.222... cece eee ccc ceeee

Himalayan pine......... 2... ec cc ee eee eee
Hippeastrum............ 0. .cc ccc eeeceeceee -

Hitchcock, A. 8.2.2... ..0 0. ccc cece cece cece es
Hoary puccoon..............000... ce cceeceees

INDEX.

Page. Page.
172 | Hog millet....... 002... e ee eee 77
219 peanut... . eee eee eee 189
174 | Holcus.. 2.22.2... c cece cece cence cece cues 72, 84
167 | Holly... eee e eee e eee eee 199
261 American..........2..2.000eee cece eee eee 199
178 deciduous... 2.2.2.2... 02. cece e eee cence 199
264 family... 2.222.222 eee eee cece eee 199
267 | Holm, Theodor.................2.02.00eeeeee 13
267 | Homalocenchrus...........22....02.0ecceecee 81
178 | Honewort........ 0.20... cece ceecececcecees 218

54 | Honey locust................0...002 cece eee 180
235 | Honeysuckle..............02..0e eee eee ee eee 259
137 bush... 2... eee cece eee enc eeees 259
243 family... 2... eee cece cece ee eee e eens 259
257 Japanese... .......... cece eee eee eee 259
222 trumpet..... 2.2... cece eee eee eee eee ee 259
244 | HOp.... 2... eee e cece ee eee ccc cecencececs 142
215 ClOVEr. 2... eee ee eee ee eee cee e eee eeee 184
251 COMMON... 0... eee ee eee ee eee eee eee 142
167 hornbeam ........ 2.0... 2 eee eeeceeeeeecee 137
243 Japanese... 2... ...0. cece ce cence cece eee 142
217 i 192
289 | Hordeum............... ccc eee ceeeeeececeees 91
205 | Horehound.............00.20.ceccceeceeeeees 242
286 Water... 2... eee een cece cee ee eeees 246
285 | Hornbeam, American..............---2--. -- 136
237 oC) ce 137
237 | Horned pondweed.............02--ceecceeces 64
120 | Hornwort........ 0.2... cece cece cece ence eee 155
122 family... 2.2... cece eee cece eee 155

98 | Horse chestnut..........0..2.00ceeeeeeeeeeee 200

61 Gentian... 2... eee eee eee eee 260
219 Be) 0 (ce -. 248
219 | Horsebrier.............. cc cece ceseeccnnecccee 125
219 | Horsemint............. 00... ccccceecceeceees 244
142 | Horseradish...............0.cce cece eee eeee - 166
230 | Horsetail........... 0... eee ec cece cece ceees 58
149 family... 0.0.0... cece cece eee eee cece 58
275 | Horseweed..............cccceceeececceececce 283
243 | Hound’s-tongue............cceeceeeecceceeee 237
157 | Houstonia.............0.. 0. cece cece cee cence 259
218 | Huckleberry. ........... 222... cccc eens eeeees 224
283 black... 2... 2c e cece e eee cece ceccece .- 224

16 Es - 224
215 DOG... ce eee eee eee cece eee e cece eee ees 224
251 | Humulus.................ceeeeeececeeceecees 142
167 | Hyacinth..... 2.2.0... .cccccccccccccccceccees 120
116 D@AN.. 2. eee ee eee cece e cece cee eces 190
171 PTAC... eee eee cece cence 122
203 | Hyacinthus. .............2. 0 cece cceceee snes 120
135 | Hydanthus..........cccceccccacccecceccccccee 206
136 | Hydrangea...........ccccccccceeeceeeeee cece 172
136 family...... 00... cece e cece eee e cen c eens 172
136 Wild... eee cece e ew eee eenccecce 172
136 | Hydrangeaceac.........2.. 2. cee ee cece ec cec cee 172
267 | Hydrocotyle..........0.22-ccccceencceccccece 21¢
203 | Hydrophyllaceae..............cc cece cee cecce 23¢
225 | Hydrophyllum..........2... 0... cece cece eee 236
260 | Hypericaceae............... 2 cece cece ccecce 204

14 | Hypericum............002 2... cc cece eee eeeeee 204

61 | Hypochaeris............. occ ees eeccccscccene 264
125 | Hypopitys. . 2.0.02... ccc cece ecenccecccees 222

14 | Hypoxis.............. 000 cc eecccceececcccceee 125

14 | Hyssop, giant... 2.2.2.0... ccc eee ec eee c ee cce 242
238 hedge..... 2.22. cece cee cccececcecceeees 251
224 WAC... eee ee cee cece ees cece een enecee 251

INDEX. 317

Page Page

HYySUtrix.. 1.022222 e cece cece e cece renee ee eees Q2 | Juncaceae........---- cece eee e cence ene eneeee 117
Thidium............---.. ee eee eee eee eeees ~ 180 | Juncoides.............eee eee e cece cece een eeeee 119
5 0), arr 199 | Jumcus.. 2.2.2 eee eee c eee eee e eee eee e eens 117
Tlysanthes......2---..ceeceeeeeeeeee eee eeeees 251 | Jumeberry...-.--------20-- eee ee ence cece eeee 178
Impatiens........-.22--2-2- eens eee e ee eeeees 201 | Juniper..........-.---------- ee ee eee eeeeeeee 61
Impatientaceae. ........-..-----eee eee rere 201 | Juniperus. ............. ee ee eee eee eee cece eee 61
Indian pgrass...........2-2+e cece eee e cece cers 72 | Jussiaea..... 2... cc eee eee ee ee cece ence en eeee 213
Hemp..........--- eee eee eee eee ee eee neces 230 | Kafir.......... 2. cece eee eee eee cece cece eceee 72
Mustard.........-2-- cece ee eceweeeeeeeees 170 | Kallstroemia.......-.-.----...-2eseeeeeeeeee 192
Pink..... 22.02. cece eee eee eee eee e ences 228 | Kalmia............. 0. cece e cece cece e ee eneeee 223
PIPe..... ewww eee e ween reece eee eee e eens 221 | Kentucky bluegrass. .........--.------+2e008 88
pipe family.................0.eeeeee eee 22) | Keys to families, preparation of.........--..- 15
Plantain. ...........22 222 eee eee e wees 291 | Kickxia.........-.---- eee ee ee eee ee ee eeeeeee 250
tobacco........2. eee ence eee ee ee eee e tees 263 | Kmawel.. 2.1.1... cee eee wee cece cee eeeeees 151
tuIMIP... 2.2.2. e ee eee cece eee eee eee ences 114 | Kneiffia...... 22... eee cece eee eee eee eeeeee 214
Indigo, false.....-.--------2eeee ence eee eeeee 184 | Kmotgrass........0.2-2---sceceeeeeeereeeerce 145
a | Cs na 182 | Kmotweed......... cc cece cece cece cece ee eeeee 145
Det) C: 284 Japanese. .......ceece see e cee en cceeetees 147
Tonactis.......2 cence eee nee e cen eeeeeeeeeeces 992 | Knowlton, Frank H...........----+------++- 13
Tonidium .........cccccee eee eccceecceeceeeeees 206 | Koellia............2--- ee ce enc eeecceeeeeecees 245
JonoxalisS...... 22... cceeeececcecceccereeeeees 191 | Komiga.............. scene ee eee ene cece eens 165
Tpecae, false. ........-22eceee eee eeeeeeeeecees 175 | Krigia..........ccccccce cence ee eceeceeceecs 264
Wid... cee cee cee eee e cece ee cee cee eeeeeeees 196 | Kudzu vine... ......... 22. ce ee eee eee ee ee 190
Tpomoed..... 2.2... cece ee eee eee e ee cen en eeeee 933 | Kuhnnia.. 2.0.0.2... 2 cece eee cence eee eeweees 275
Tresine.......... cc cececceccecccceceeecceceees 149 | Kyllinga. 2.0.02. ... cece e eee ee ee eee ee ce ners 95
Jridaccae. .....----.- cee cccuccececccccececees 126 | Lacinaria............ceee eee eee e eee e ee ences 275
S55 126 | Lactuca..... 2... cece eee cece cece eee eeeee 266
CTOSTCD . oe. eee eee cence cence eee nwenneee 126 | Ladies’-tresses.........2-.20eeeceee ee eeeeenee 130
family 22.2... ... cece eee eee eee cece ee eeee 126 fragrant... ......0---esee ence eee e tee eeeee 131
SPTING .. 2... 2 eee ceeeeee cece cece ence eeeees 126 | Lady fern... ......... 2. eee eee e eee e eee neenes 56
Tron-weed ....--2- 222 e cece cece cece een eenees 973 | Lady’s-mantle............-0----eee eee eeeee . 17
yOllOW......--ceeceeeeece nese eeeeeeeeeeee 287 | Lady’s-slipper..........---eeeeeeeeeceeeeeeee 128
Tronwo00d..........e2ece cence cece cece eeeeeees 137 yollow.-.....----.seeeee we enceccececcesee 128
Tganthus........-.ceeeeeeeeee cece cence eceeees 941 | Lady’s-thumb...........22.cccseeeeeeeeeeees 146
Jsmardia......-ceceecceccececeeesecccececeees 913 | Lake cress.........-.-0eeee seen eee eeeee saceee 166
Tsoetacene. 20... ccccccecccccccccecsacseceeas 60 | Lamb’s lettuce............-2202----- ++ seeee 261
TsoeteS.....---2e sce ce cece eee ceceeeeeeeeeeeus 60 | Lamb’s-quarters.............eseeeeeeeeeee -. 148
Tsotria.......-.----ceeeecceceeccecceeceeeeees 130 | Lamium... ...........2.-- eee geeen ee eeeees . 248
1: 172 | Lance-leaf violet..........----.----eeeeeeeeee 208
Ivy, Boston.......-.--2--eeeee eee ee eee e cere 201 | Laportea..........-.- cee cece cece cece eee eeees 142
English. ........-----2.--ee eee eee eeeee 215 | Lappa.... 2.2... cccceeec eee e cece eee ceeeeees 292
PT 243 | Lappula........ 2222.22. cece ween eee eee e ees eee 237
POISON... 0.622.222 eee e eee eee e ene eens 198 | Lapsana..... 2.22. sce e ence cece ence cece eee 264
Ivy-leaf speedwell......----...e-seeseeeeeeee 252 | Larkspur.........-.-----see-seeeeeeceeeeenes 157
Jack Oak... ..... cece ence ence eee e ee ee ee eecees 139 Chie) nes 157
Jack-in-the-pulpit ..........2.----.-seeeeeees 113 a) <: | ere 157
Jacob’s-ladder.......-.--------e+-eeeseeeeeee 935 | Lathyrus.....-..----.0..eeeeeeeee reece wese = =189
Japan Clover. ...-.--.-2-ee- cece eee e ee eee eens 187 | Lauraceae..........2..-. cence eee e eee eee eee 161
Japanese honeysuckle. ........-------eeeeee: 259 | Laurel family. .................-e eee eee eee ee 161
HOP. . cece eee eee eee re cece cece ence ceeeeees 142 mountain. . 2.2.2.2... cece eee eee eee eens 223
Knotweed. .........2.eeeceeeee eee e neers 147 SHOOP..--...ee eee nee eee eeceeereereeeecces 223
Jasmine... 2.22... ceeeeececeeceeeeeeeeeeeees 227 | Leafcup, large-flowered...........-----+---++ 285
Jasminum..........eee eee eee eee eee eee e eee 227 small-flowered...........cceeeecceeeeeees 285
Jeffersonia..... 2.2... eee ee ee eee eee eee eee e eens 160 | Leather-flower. ............--eeeeeeeeeeees -- 160
Jerusalem artichoke. ......-----------+eeeees 297 | Leatherwood........----.--ceeseeerecceeceee 211
Cherry...--... 2-2-2 e cee ceeeeeee eee eeeeees 247 family......2-.2.-0-ee eee eee eee eeeeeeees 211
RY 148 | Lechea.......... eee seen cee e een eee ceeseee 205
Jimson-weed. ...-----0--- eee e ee ee ene eeeeeeee 247 | Leek... .....cceceew reece eee c ens eeeeneeneeecs 121
Joe Pye weed......222---..eceeeeee eee e ee eees 274 a0 Cs 121
Johnson gQTass. ....---- 2. cece eee eee eee e eens 72 | Leersia.. ........cceceen cece cece ces ceeeeeeee 81
Jonquil.......2.ceceeeeseceeeceeeeceeseeeeees 105 | Legouzia........-20-2.eeeeeee eee eee eee eeeeees 262
LOMB . 2. ee ee eee eee cece ener enee 114, 115

Judas tree... 1... eee eee cece cece cece eeeeeee 180 LOMNACeae... cv cccccccccccsssecccseceeeees 114
Juglandaceae. ........cee eee e eee e eee ceeeeeee 135 Leontodon .....ccccccccenccececcccccceeees 264, 265
Juglans... 2.2... e cece eee cece eee ee weees 135 | Leonurus........--.--eececeeccecececceceeces 243
Jumpseed ......- 2-2 eee cece eee c cece eee ceneees 145 | Leopard’s-bane...........ceee cece enone wee 291

318 INDEX.
Page Page
Lepidium..............0.000 00 ec eee eee eee 166 | Lonicera..... 2.0.00... cece eee eee ee eee eee 259
OL 151 | Loosestrife.......... cece eee eee ee eee 212, 225, 226
Leptamnium....................00ce eee eee 255 family. .... 2.200.200... cece eee cece cece 211
Leptandra................ 002. cece eee eee 253 fringed..........2...2..2..0005- cent eeeee 226
Leptilon... 22.2.2... cece eee eee eee e eens - 283 PUIPle... 2.2... eee eee eee eee eee cece eee, 212
Leptochloa... 2.2.2.0... cece cece cece cece cece 85 SWAMP. .... 0-2-2 eee eee eee ence eee eee 212
Leptorchis...............022 2 2c eee eee e eee ees 131 | Lophanthus...........2..2.. cece cece eee seen 242
Lespedeza....... 22... c cece cece eee e cee eeneece 187 | Lophotocarpus....................02000-000e 65
Lesser celandine................202eceeeeeee 159 | Lopseed.............. 02 cece cece cece cece eees 256
Lettuce... ccc cece cee e eee 266 | Loranthaceae..................02 cee eeeeeeeee 143
10) 00 266 | Lorinseria..................0ccc cece cece cease 54
Florida... 2... 02.2... cece cece eee ee eee 266 | LOtus...... 2.2. eee ccc eee eee nec e cece ee eaee 184
lamb’S... 2... eee e eee cece eee ce eee ee eee 261 | Lousewort, swamp............2-2..000 eee 254
prickly... 222.2... ee. cece cece cece cneee 266 | Low cudweed................. cece eee eeeeaee 284
1 223 | Ludwigia....... 2... eee eee eee cee eee 213
Lewton, F. i... 2... eee cece e cee eenee 14 | Lungwort.............. cece cece cece cece en ens 238
Didsris .. cece cece cence eee e nee 275 | Lupine, wild. ...........2....0.. ccc c cence ee 183
Licorice, wild... 2.2.22... 000... e ec ee eeeeeee 258 | LupinuS........2...22.. cece cece ceceeeeeeeees 183
Ligustrum... 2.2... cece cee eee cece eee 228 | Lychnis................. cece eee ceeeee cence 153,154
BU 227 | Lycium......... 2.2.2... cccecececccccceceeeee 247
Liliaceae. . 22.22... 0.22 e eee ec cence eens 120 | Lycopersicon.................00cceeeeeeeeees 247
Lilium... 2.2... c cece cece 121 | Lycopodiaceae.................cccceeeceaeees 50
0 121 | Lycopodium................cceceeccecceeeeee 59
blackberry. .............. 2.00022 eee ceee 126 | Lycopsis......2.... 0... cece ees 239
Canada... 2.2.2... 2. eee cece cece neces 121 | Lycopus........ 0.0... cece eee e cece ese eeees 246
family... 2... 2. cece cece cee cece eee eee 120 | Lygodium.................0cceeceeeeeceeeeee 53
orange day... 2.2.0.2... 22 c eee eee eee 122 | Lyonia..... 22.0.2... cece ee cece deccceccccuuees 223
OT) 121 | Lyre-leaf sage.............20..22ccceeeceeeeee 244
0) 122 | Lysimachia...................0eeeeeeeeeeeees 225
TUrk’S-Cap. . 2... 0... cece eee eeeece ee eee 121 | Lythraceae............ 0.0... .cc eee eee eee eee 211
WO0d......... cece eee e eee eee cececeeeees 121 | Lythrum..................cce cece eee eeee ees 212
Lily-of-the-valley..........00 2... ce eee eee 123 | Maclura. ......2.... 2.2.0 c cece eee ccecenceces 141
family... 2.0.0.0... cece eee cece ence ceeeee 123 | Macrocalyz .......2..2 ccc cece eee ee cee ce cence 236
wild............... ween cece ee ceeeescncnes 123 | Madder family..............0 0022. c eee ee eee 257
Limmanthaceae...................0000ee eee ee 198 saC:) (6 a7
Limodorum................0202000eeeecaceee 130 60 258
Linaceae. ........... 222 cece eee eecccccceceee 192 | Mad-dog skulleap............0.0 0c c cece eee 242
Limaria.. 2... 22... ee eee cece ceceee eee ee eeeee 250 | Magnolia................ cece eee cece eee eeeee 161
Linden... 22.0.2... cece ccc cece ce ccenteence 202 family........ 202.0... cece cence ee eeeceee 161
family... .. 2.00... eee cece nee cceeeee 202 SWAMP... 2... eee eee cece eee eee eee ee 161
Linum... 2.2... eee cece cece eee ceeuece 192 | Magnoliaceae..............0 2. cece cece ceeee 161
Lion’s-foot.... 2.2... 0c elec eeeeccccceuceee 265 | Mahaleb..........22.......cccccccee cece ee ees 180
Liparis... 20.0... 02.0.2. ece cece eee ee eee c eee 131 | Maianthemum, ........0.0.0.0 00 e cece eens 123
Lip-fern. 2... eee eee eee 55 | Maidenhair................20.. 00. cc cece cece 55
Lippia... 2... cece ce cece ccc ceece 239 Spleenwort.............. cece ee eee ene eee 56
Liquidambar........2.2..........000---00-5- 173 | Maize....... 00... eee eee cece cece eee 66
Liriodendron.....................00000--000e 161 | Malaceae...........2..2222 2.22 cee cece eee 177
Distera... o.oo ieee cece cececncneccecece 131 | Malaxis..........0... 0000 c cee eee eee ceceeee 131
Lithospermum..............000...2200-0005. 238 | Mallow, curled..................0020.. cece eee 203
Little bluestem...............0000000ceeeee ce 72 5) bl 203
Live-for-ever . . 2.2... . eee cece cece eee cceceeee 171 family... 2.22.2... e eee eee 202
Wild. 22... e ccc ceeee cece eens 171 high.... 2.0... 0. cece cece ence cece ence cease 203
Lizard’s-tail........ 0.00... cc cece cence eee 132 | Mallow, musk...............2......0022200.. 203
family... 2.2... eee eee cece cece cece 132 TOS@... 0... cece eee eee cee eee een ccccccee 204
Oe: a 263 SWAMP... 2.22.02. 2 eee eee e cece eceececeee 204
family... 2... lee. c cece cece ces cce cece 263 Virginia... 22... cece eee ee eens 203
i) 263 | Malus... 2.022... 2 cece ae cee ccc eee ceeeeeees 177
Lobeliaceae.... 2. ....... 002 cece eee eee eee e eee 263 | Malva......22. 2... cece cece eee cnc eeeeaeees 203
Loblolly pine............ 0. eee cece cece ee eee 61 | Malvaceae....... 00... cece cece cence ee 202
Dodbularia.... 0c. cc ccc ccc c eee ccc cecncccccece 165 | Mandrake..............02..0 cee ee cece acces 160
Locust, black... 2.2... .......cccccececeeneeee 185 | Maple............ 2.22 e eee cece eee 200
NONCY........ eee eee cee eee eceeececccees 180 family... 2.2.22. 0 2... cece cece eee eens 200
Logania family ...............0000..000002005 228 Norway..... 2.2... cece eee eee cee cca ee 200
Loganiaceae........ 2.2... e ce cccce enc ccecees 228 6 200
Lolium... 2.2... eee c ccc c cence eccee cece eee 90 Silver... 22... c ccc eec cence eee eee ee 200
Lombardy poplar.............0...0...0.0 00s 134 St) ce 200

INDEX. 319

Page. Page

Maple, SWAMP........... 0. eee eee eee .-- 200 | Milkweed, red..............2.....00 ee eee eee 233
SYCAMOTC..... 0... cece ee eee eee e eee cece 200 SWAMP... 12. e eee eee eee eee eee eee eens 233
Maracocks. ............... cece eee eens e eens 211 White....... 2. cece eee cece ee eee cee ween 233
Marginal shield-fern...............-.-------- 58 | Milkwort......-....---.-.2---.--2 22 eee eee eee 193
Marigold, bDur............ eee e ee eee eee eee 289 family..... 2.2. ee cece cece e cece cece ee eeees 193
Marjoram, wild..................2.22...0000 245 | Miller, G.S., treatment of Apocynum....... 230
Marrubium............... 0. see e eee eee eee 242 | Millet........--.22--- 0-22 eee eee eee eee ee 80
Marsh fern...........-2.0.0 cee ee cece eee cece 58 DIOOMCOIN........0... cc ceesceeeessceeees i7
fleabane............... 20222. c eee eee eee 283 NOG... 22. eee eee eee eee ees 77
pennyworlt........-....- eee eee eee ee ee eee 219 | Milo........... 22... e eee eee cece eee eee eees 72

St. John’s-wort............02-ee cece enone 205 | Mimulus..............--2.. 0202 e cece eee eeeee 251
speedwell.............0.0.. 202 ee cece ee eee 252 | Mint, bee......-.....---... 2.2 eee eee eee ee eee 245
Marsilea........20..00ceeceeeseeeceeeeceecees 58 family ......2-0.0c0200ccceeceeeeeeeeeeees 239
Martynia.........0.... 2 cece eee eee eee ee eee 254 Wild... 2.2.2. cece eee eee eee eee eter eee 246
5) 290 WO0d ... 2-2 eee ee eee eee eee eee cence ee eeees 244
Massachusetts fern............202sceeeeeeeees 58 | Miscanthus..................- nent eeteswcenes 66,71
Matrimony vine.....................0--00+ .. 247 | Mist-flower...............2.00-2.e cece ee ee eee 275
Matteuccia..... 20.0... cece eee eee e eee ee eee 54 | Mistletoe....-....-.-. 2. eee eee eee eee 143
Maxon, W, R........... 2-0 cece eee e ee ee eee ee 14 family ........ 202. .e ee cece eee eee eee 143
May-apple............ cece ccc eceeeewceceeees 160 | Mitchella........................e cece ee ee eee 258
Maypops...........--. ee ee cence cece cece eeees 211 | Mitella.......... eee eee eee eee eee ees 172
Mayweed......... weeseeerece wee e cece nccneee 290 | Miterwort.................. 0.0 eee ee cee eee eee 172
Mazus... 22.2.2. c cece cece ee ee cence en eeneece 251 false... 22.2... e eee eee eee eee eee e ee eee ees 172
McAtee, W. Li... 2... eee eee eee e eee e eee 14,20 | Moccasin flower. ...-....----------- ee ee eee 128
Meadow beauty. ..........22...e eee eee eens 212 | Mock bishop-weed.......--.---------+2-eeee0+ 219
family... . 2... cece cece eee eee cece tence 212 | Mockernut. . ..........-cee cece eee eee eeeee 136
fOSCUC..... 22. cece ee eee eee renee ee eee 89 | Moldavica................-. 2. sees cece e cence 243
garlic............. oe cece ee ec es ce ee eeeeeee 121 | Mole plant...........---.02- cee eee eee e eee ees 197
parsnip............. wees e cee eeeceeeeeeece 218 | Mollugo. ........... cece cece cece cece eee e ene 150
Meadow-rue...... 22-2. e eee ee eee eee eee eeee 159 | Monarda. ...........---- 2. eee ee eee eee eee ees 244
Meadowsweet........----02e- cee ee en eeeeeeene 174 | Moneywort.....-....-.-...----20- ee eee eee eee 226
Mecardonia...........cceeececeeecececcececes 251 | Monkey flower. .......-.-.------+----+eeeeees 251
Medeola.. 2.2... cece cece cece eee een eeeeee 124 | Monkshood.....--.... 0-2... cece eeeeeeeceeee 157
Medic, black.............-.---2--06- peccecees 183 | Monotropa........--.2-.--22.ee cence eens 221, 222
Medicago.............-ceceeeeeeeeeeeeeeecees 183 | Monotropaceae. .......-.----.eee eee eee eee 221
Meibomia...........2- 2-22 e ee ec cece ence ee ees 185 | Monotropsis..............020seeeeeeee ee eee 221
Melampyrum........-0-.- eee eee eee eee ee enone 254 | Moonflower.......-----.----ssseeeeeeeeeeeeee 233
Melanthiaceae.......... cc cc eew eee ec eee eeeees 119 | Moonseed........-....5- 2 eee e cece ee eee ences 161
Melanthium.......... 0.0... ce eee eee ee eeee 120 family ..........0ee cece wesc eee eee ences 161
Melastomataceae... 2.22.2... ele eee nsec eeeeee 212 | Moosewood........-2--- ee eee eee eee eee ee eeeee 21t
Moelica. .. 2.2... eee ee ee eee cece eeeeees 87 | Moraceae. ...........cee eee eee cece rece ceeeees 141
Melilotus..........-.-0.--- eee cece cece ee eeee 183 | Morning-glory ...-.....--.-.seeseeeeeeeeeeees 233
Melissa........2---- 2-22 eo eee e eee eee een eee 244 COMMON. ....-.- 2. . cece cece cece ee eececes 233
Menispermaceae.......----..----2e-2ee sence 161 family ......-------e-ee cece e cree cece eeees 233
Menispermum.........-----.2--02e- eee eee 161 small red. ...-....---2eee eee e eee eee eeee 233
Mentha.........0-2. 02 eee e eee eee cere ee eeeeee 246 | Morus.........-...2---- eee cece eee ec ence eens 141
Menthaceae.....---...2- 22s cece ee eee eee neces 239 | Moss pink....-..-..-.--..seeeeweeeeesceeenes 235
Mercurialis. .........-.2220- 22 eee cee e cence 195 | Moth mullein........-.......- 02. eee eee eee ees 250
Mercury, three-seeded.........----..--+-+0+- 195 | Motherwort......-.-------------eee-: wececee 243
Mermaid, false..........-2-2--2e--e sence cence 198 | Mountain laurel........-...-------------+++- 223
Mermaid-weed.........---- cece casceeeresenes 215 spleenwort. ...---.---------e-ee eee eee 56
Mertemnsia..... 2.2... cece cece eee ee ee eee cence 238 | Mouse-ear chickweed......---.------------+- 152
Mesadenia.....,..-....cecccceeeeeceeeeeeecees 291 0 168
Micrampelis.........-.. 20.00. ee eee eee cece ee 262 | Mud plantain..........--...-----eeee seer eee 117
Micranthemum, ...-..........00eee eee eee eee 251 | Muhlenbergia....-.--..-----------++-- ceeeeee 82
Micranthes ......- wee eee eee nee e nee eee eres 172 | Mulberry.......---.-----------e eee eee eee eee 141
Microstylis. ..-.....-02022 cece ence eee een eee 131 family ........--0- ee eee cere eee eee eee eee 141
Mikania. ..........- 0 eee eee eee eee ence eee eeee 275 502) 0) ane 141
Milfoil, Water.......-..--------eee cece eee eee 214 56 141
Milk pea....- 2.2.2 c cece e ee eee eee eee ee eee 189 white.....-.--2 25. cee eee eee ee ee eee ee eee 141
pUrslane.......--- 20 cence ee eee cence eee 195 | Mulgedium.. ..-..-..--0.- eee eee eee eee ee eee 266
57:) 0) 6 185 | Mullein......--.....-- 00sec eee eee ee eee eee eee 249
Milkweed, Common......----------+-----eee 232 MOth..... 22-2 e eee eee eee eee eee eee eens 250
family ...-.. 22.2.2 c ee eee eee eee eee eens 231 | Muscari. .....-------- 2. eee ence eee cece e eee 122
green-flowered.......-2+-------eee eee e eee 231 | Musk mallow. ......-.-..0seseseeeee eee eeecee 203
PUIple. .-- 22... eee cece cence eee eee eeee 232 thistle. ...-.-- 22... cece eee eee eee eee ee eee 292

820 INDEX.
Page.

Mustard, black...........0......ccccceeeeees 170 | Oak, black......... 00... ccccccccccc cee c cena
family ...... 2.02. cece cece eee eee ee eees 163 LO ce
0 167 Chestnut... 2.2... cece cece cece eee ee
NS 167 Le
hedge.......- cee ec eccee eee ee ence eeees 167 Jerusalem. ............0.ccccceecee eee ees
Indian........... 00... c ccc cece cece eee 170 PID... cece eee e cece ee
tumble. .......... 2-2. eee eee eee ee eee e eee 167 |) es
20 cs 170 6 ee
WOTMSCCd . . 2.2.0... eee e eee eee eee eee eee 167 rock chestnut.............0--ceeesceenees

Myosotis. . 0.2.0.0... 2... cece cecceecccccceees 238 Saul’s...... 2... ccc eee eecc ee cecccceee

se 135 9 (es

Myricaceae..........2..00.eee cece eeeeeees 135 scrub chestnut...........0.....cceceeecee

Myriophyllum..................02c00eeceeeee 214 Shingle. .......2 22.22. ccecceeceeeeeeeeeee

Myrtle... - 2.2... c ec ccecceerecee ones 230 Spanish. ............0 cece eee eee ncecccee

Nabalus......... 0000... cece cece cece eee e eee 265 swamp white. .... 2... c cece eee

Naiadaceae....... 2.02... cc cece cece ce ccences 64 white... 02.2... ccc c cece c cece cc encucuce

Naias..... 2.2.2... cee cece cece ce cece caeeee 64 WIIlOW... 2.2.00. ce eee cece eee c cen canccuce

Narcissus. ........0.. 22... .c cc ccc eee ee ee eeees 125 | Oakesia. .. 2.2.0... cc cece ee ccccececccccceccces

Narrow dock... ...........c000ceceeececcecees 145 | Oat grass, tall............ 2. cece cece eeeeeeeee

Narrow-leaf vervain..............0020.200005 239 | Oats........ 2.2 ccc cee ccceeeenaccceccccccuss

St 166 | Obolaria.... 2.2... 2. .cccccccecccecececceeeees

Needle grass...-..........00ccc eee eececcccees 81 | Odostemon............00.- cece eeccccccccees

UL 200 | Oenothera................ccececccenccceeecee

Neillia... 20.0... e ccc cee cc cece ec ccc ccc ceees 173 | OKra..... 2... cece cece cccccccceccececnceeccs

Neobeckia............ 0... c cece cece cece ecccce 166 | Oldenlandia........ 2.00... .cecccccccccecccee

Neopieris.................cccccceccecceeeeeee 223 | Oleacea@........... 0. ccc cece ee cccccccccecccce

Nepeta .... 2.0... eee eee ce acne eeeee 242,243 | Oligoneuron...........2-2cecccceeeeccccecccce

5 ee 212 | Olive family......-..........cccccceceeeeeeee

Nettle... 2... eee cee cece eeceeee 142 | Omagraceae..... 2... .......cceeceeceeece cence
dead... elec cece ee cece eeeee 243 | Onion, common.,............20..20.ceeeeeees
false... 2.0... elec cece cece ec ee eee 143 2) C0 Oa
family. ......... 0.20.22 e eee eee eeeee eee 142 | Onoclea......2.......cccecceccccccccceeeeees
hedge....... 2... ee eee eee ceeeeeeccceeees 243 | Onopordon..............22.cccceeeeecceeaees
0) 248° Onosmodium.................ccccececceeeeee
A 142 | Ophioglossaceae..............c0-eecceceeeees

Nettle-leaf goosefoot..................20ceeee 148 | Ophioglossum...............e0eeeeeeceeceees
SABC. cee eee cece ene c cane nce eccacecaucne 244 | Ophrys...... 0.00... ceccc ese ccccccceecccccee

New England aster...................2.20005 oC

New Jersey toa... ......... ee eeee cece eens eens 201 | Opuntia.......... 00... c cee cece ccc eeeceeecee

Now York fern..............0ceecceceeeeeeee 57 | Orange cone-flower...........2....0ceceeeeee

a 247 day lily......... ccc cece eee eeec cece wees

Night-flowering catchfly,.................... 154 OSABC. 0... e eee c cece cece nce cncececcees

Nightshade..... 2.2.2.0... cece cece cece ne 248 | Orchard fe ee
enchanter’s...............200.ceccceeeeee 213 | Orchidaceae............200-2220ceeeeeeeecees
0 247 | Orchis.............0.cccccccc cece cceececcecee

Nimble Will...... 2.0.0... c cece cece cece cceee 82 crane-fly...... 2.2.2.2... eee cece eee eee

Nine-bark........ 2.0... ..ce ce ceeeeeeeee ee ee 178 family ......... 22... s cee cee eee e cece eeees

Nipplewort...... 22.0.0. 00.00. cccce ccc ceceeee 264 purple.......... 22... eee eee cece e cece

Nodding chickweed.................0ce0e005 152 ragged fringed...................0222000-

Nomenclature, American Code of Botanical.. 16 0) 5 A

a 167 white fringed..............0.......000006

Norton, J. B....... 2.22... ce ce ceeeceeeccee eee 14 yellow fringed.............0..-.0...000.

Norton, J. B. 8.0.2... 0.0.0.0 c0ceececeeae eee 14 | Origanum......2........... cece eeeeeeecees

Norway maple........ 2.2.0... ceeeee 200 | Ornithogalum............... tt eee eeeneeeeee

Notholeus,.......... 2.2.2.0. e eee cece ce eee 84 | Orobanchaceae..................eeeeeeceeees

Nuphat.... so... cece ccc cece ene eccccccccceee 155 | Orobanche..........-...0..ccceececeneccecee

Nut grass................ccccceccceccececeees 94 | Orontium................ 2. ceeceeeececcceee
1) 99 | Orpine family.................... 02 cc cece eee

Nyctelea............. 0.2 e eee e cece ec eeeeeeeee 236 | Osage orange.............. 02 ce cece eee e eee

Nymphaea...... 2.2.2.0... cece ee cccecnee eee 155 | Osmorrhiza............0.. 0.002 e cee cee neces

Nymphaeaceae,...............0c. cece cece ees 155 | Osmunda............. 00... cece eee een eaee

SL: ee 220 | Osmundaceae........-........ ccc eee scene eee

01.) ce 138 | Ostrich fern....................c0cc eee eee
Bartram..... 2.22... 0 22.0 cece cece eee eeee 139 | Ostrya..... 2-2. cece cece cece cece cece eee
basket... 2.222222 l eee cece cee eee eceee 140 | Otophylla...........2.. 2... eee ee eee eee
Le) 140 © Oxalidaceae...... 2.22.22... cece e eee eee ee

INDEX. 321

Page Page.

Oxalis...... 00.02.20 e eee eee eee eee ees 191,192 | Penthoraceae...........-.-.----+0--- 222222 e+ 171
OX-CYC. oo cece eee eee eee eee eee eee eee eee 285 | Penthorum................---- eee eee e scenes 171
aisSy.. eee eee ce eee eee eee eee 290 | Pepper vine........-.22.---2. eee eee eee eee 202
OryDODhUus.. 00.0... e cee cece ce cee eee eee ee 149 | Pepperbush, sweet ........-.--------------- 220
Oxypolis....-...--.220 02222 eee cece ence eee 218 | Peppergrass..........2.-0s002eeee- eee eee eee 167
Oyster plant...........2.0022 2 cece eee 264 | Peppermint...............202-ee eee eee ee eee 246
Pale touch-me-not..........2....-----25-0-e- 201 | Pepper-root..............-2.2--20-- eee eee eee 169
PANAX 2. ee eee eee eee ee eee eee cece e ee eee 215 | Peramium...........-..---------2----+------- 131
Panicularia................-0202 0c cece eee eee gg | Perennial rye grass...........--------------- 90
Panicum ..........eeee cece eee cece eee ees 78,74,80 | Perilla............-2-02-- ee eeee eee ee eee eee 246
PANSY... 2. eee eee cece e eee e ene e cence ence ces 208 | Periwinkle.............-.---2-2-2- 2222 eee 230
field... c cece cece eee ee eee eee ees 208 | Persicaria..........0..... 00 ee eee ee ee eee eee ee 145

Ba (0) ) a 208 | Persimmon.........--.--2-..seeee eect eee eee 227
Papavel............. ccc eens cee eee cece ee eee 162 | Perularia............0-220222 22 eee eee eee eee 129
Papaveraceac..........022..2 eee cence eee eee 162 | Petunia:. 2.2.2.2... cece eee eee eee eee eee 247
Paper mulberry......---.--------2e- eee eee 141 | Phacelia......... eee cece cece e eee cece eceees 236
Papyrus. ............ cece eee eee eee eee ee ee eee 141 | Phaethusa..... 0.0.0.2 2c ee eee ee eee eee ee 288
Pardanthus........ 00-000. c eee eee eee eee eee 126 | Phalaria..........02.02. 2.0202 e ee eee cee eee 81
Parietaria. ...........02- eee ence cee eee eee 142 | Phaseolus............22.-22-2-200- eee eee -. 190
Paronychia... 2.2... cece e eee eee eee eee ee 151 | Philotria.... 20.20.0200. cee ee eee eee eee eee 66
Parrot’s-feather.............00---2005 geceeees 214 | Phleum................0022- 02222 -ee eee eee 83
Parsley family.........20--2. 22-2 - eee eee ee eee 915 | Phlox. .....2.2... 022.2 eee eee eee eee 235
hedge. ..... cece cee cee eee eee eee eee eee 217 Due... 2. eee ee ee ee eee ee eee 235
Parsnip... 2... eee ee eee eee eee ee eee eee eee: 218 family... 2.0.0.0... eee ee ee eee ee eee 285
COW eee cece cece eee eee erences 218 parden.........222 222 e ee eee eee eee eee 235
MCAdOW.... ee ee eee eee eee eee eee eee ee 218 | Phoradendron..........--..----.-----+------ 143
ParsOnsid.........--02- eee eee eee eee eee eee eeee 212 | Phragmites..............2..----------------- 86
Parthenium............--.2--2--225-2- eee eee 285 | Phryma......... 22.20.0022 e eee eee eee ee eee eee 256
Parthenocissus... 2.2.2.0... 200. e eee eee eee 901 | Phrymaceae...........--0---00+22-- eee eres 256
Partridge pea..... 2.2.22... eee ee eee eee eee eee 181 | Phyla....2.... 22-22 eee eee eee ee eee ee 239
Partridge-berry.......2.-2---2-2-2 0202 eee eee ee 258 | Phyllanthus...............2---------------5- 195
Paspalum... ......2.22 00 eee e ee eee ee eee eee 73 | Physalis.............. 020002 - ee eee ee ee ee eee ee 247
Passiflora... 2.22... eee eee ee ee eee eee eee eens 211 | Physalodes..............2-----2-+- Lecce ee eee - 247
Passifloraceae..... 22sec ee eee ee eee cece eee eee Ql1 | Physocarpus.........20-222202e0eee ee eee eee 173
Passion-flower.....2.....-e eee cece ee ee cece eee 211 | Physostegia......2....2-2220-2222 2-2 eee eee 243
family... 0... cece eee ee ee eee eee ee eee eens 211 | Phytolacca.............-..-----2--- eee ee eee 150
Pastinaca ...... 2.2.2. e ee eee eee ee eee eee 218 | Phytolaccaceae.............--------------+-- 150
Pasture thistle...........0.02. 20 c eee cece eee 292 | Pickerel-weed.........-...------+------------ 116
Path rush... ........-2e eee eee ee eee eee eee eee ee 118 family.........------- 2-2-0222 e eee eee eee 16
Paulownia.... 2.0.2.0... eee eee eee eee ee eee eee 250 | Piedmont Plateau, geology of..........-..--- 16
PaWPaw....... 2 cece eee eee eee eect enter eens 161 flora Of.........----- 2-20 e eee eee eee eee et 17
Pea, butterfly........ Leen ee eeeceeeneeeeeeees 189 | Pignut hickory.........-..--------------+--- 136
COW cee cece cece ccc e eee eee cece ee eeees 190 | Pigweed.............----------e---- 2-02 - ee 148, 149
everlasting. ..........22.20- eee eee ee eee ee 189 | Pilea. ....... 22.22. e eee eee 143
family... 2.22.2. eee eee ee eee eee ee 181 | Pimpernel...............-.----- 022+ eee eee eee 226
MAK... eee eee ee eee 189 fals@. 2... eee cece eee eee ee eee eee 251
partridge. .....2-2.2. 2... ee eee ee eee eee ee 181 yellow... 2.2.2... 2 eee eee ee ee ee eee eee ee eee 218
potato...... 2... cece eee eee eee eee eee ee 189 | Pimpinella..........2.2--+--+--+-2-2- +2222 ++: 218
SONSILIVE.... 0. eee eee eee eee ee eee eee 181 | Pin oak... 2.2... 22. eee eee eee eee eee eee eee eee 139

a8 0 6 cs 189 | Pinaceae. .....-..... 222s eee ee eee eee eee eee eee 60
Peach... 2... cece cece cece eee eee eeeereeeees 179 | Pine, Austrian. ...........2.----+------+--+- 61
Peanut, hog........-2-2 0.2 eee eee ee eee ee ee eee 189 family.........00..- 2-22 ee eee eee eee cece 60
Pear... 2 cece eee eee ee eee eee ree 177 PTOUNG ......2 2. eee ee eee eee ee eee ee eee 59
Pearlwort.......--2-2...22-2--+---- wee eee eee 173 Himalayan................2222+--+------ 61
Pedicularis. ...........222-220020000-00 00-22 ee 254 loblolly...... 2-2-2 eee ee eee eee eee eee eee ee 61
Pellaea..... 22-2... e eee eee eee eee eee 55 pitch... 22. e eee eee ee eee eee eee eee 61
Pellitory .......-.-. 22-2 e eee ee eee ee eee eee 142 TuNNING.. 2.20... 2 eee eee eee ee eee 59
Peltandra.. 2.22.2... 2. eee eee eee eee eee eee 114 STUD... ee ee eee eee eee eee 61
Pencil flower. ............. 2.02022 e ee eee eee eee 185 table-mountain................---------- 61
Pennisetum... 2.2... cee eee eee eee eee ee eee 66 white.... 000.2222 eee cee eee eee ee eee eee 61
Penny CreSS......-..-.----+++-0-- eee eeeeeee 167 yelloW......... 2.202.220 ce eee eee eee eres 61
Pennyroval......-2-...2---+ cence cece eee eee 944 | Pinesap...........-2-2- 002 ee eee eee eee ee eee 222
falS@. oe eee ee cece cece cece ceceeeeeeeeeee 241 SWeet... 2.2.0 cece cece ee eee eceeeeeeeeeees 221
Pennywort...-.-... 222 eee eee eee eee eee eee 229 | Pinguiculaceac.........-...----+---+-2-+-+-- 255
MATS... ee eee eee eee eee eee eee eee eee 219 | Pink azalea......2... 2.22. eee ee ee eee eee eee ee 223
Penstemon......... 20.22 ee eee eee eeeeeeeeee 250 Deptford ...... 0.2.2. eee eee eee eee eee 154

69289—19——21

322 INDEX.
Page. Page
Pink family 2.00.0... cee ee eee cece ce eee 153 | Pondweed, bushy......................... 64
PTOUNG . 2... ee cece cece eee ee ee ee ee 235 family... 2.0.2.0. 0022 eee cee eee ce eee 62
Indian... 2... eee cece ee cee eens 228 horned... 2.2.2... eee eee 64
MOSS... ee eee eee eee eee cece eee 235 SAQO. eee cece cece eee 64
Wild... 2. eee cee eee eee 154 | Pontederia.......20000020000.00......-02 0. 116
Pinkweed ..... 2.22... 0 2.0 e eee eee eee 146 | Pontederiaceae................-0 000000 eee. 116
Pinweed.-... 000000. eee ee 205 | Poor-man’s weather-glass..............--.... 226
Piper, ©. Ve... eee eee lec seeeee 15 | Poor-weed........00....000 ccc cece ee eee ee 258
Pipewort.. 2.0.2.2... ee cece c ec ee ee ee ee 5 | Poplar... eee 134, 161
family... 2.2.2. e eee ee 115 Dlack.. 2. cece ee eee 134
Pipsissewa ... 2.2.6... eee eee ec eeeee eee ee 221 Bolle’s..... 0.22.20. e eee eee eee eee 135
spotted...... whee cee cen ee ceestesacucaes 221 Carolina... 2.2.2.2. eee eee ee 134
Pitch pine... 22.20... ce eee eee cece cece eee eee 61 QTAV. eee 1B5
Pitcher-plant.. 2.0.00... 0000002 c cece cee 170 Lombardy...........200000 02.2022 e cece ee 134
family... 2.02... eee eee eee eee 170 SS) 135
Plantaginaceae........ 222.2000 00ceeceeee 256 SWAMP... 2... eee eee eee ee 135
Plamtago.. 2... eee cece ce cece cence 256 white... 000202. 135
Plantain. ..5. 00. eee ec eee ee 256 | Poppy... 2.0... c cece cece. 162
bottle-brush.......0....0.000020-.0 22 ee ee 256 family.....0 22002222. bene eee eeeeee 162
COMMON... 2... ee eee eee eee ce cee 257 prickly ..... 222220022 162
English.... 000.20... . 0222 257 | Populus... 2.00.22. 000. 134
family... 2.00 eee 256 | Porteranthus.........................--. 175
heart-leaf... 2.0... eee eee eee 257 | Portulaca....... 20022220... oe eee. 150
Indian... 0.0... ce eee ce eee 291 | Portulacaceae.........2.000.00.---000 0-2 150
MUG... cee cee ce eee ee 7 | Post oak..... 2... eee cece cece eee 140
TODIN’S . 2... cee eee cee ence 282 | Potamogeton.......................2........ 62
Wat? eee cee eee 64 | Potamogetonaceae......................... 62
Platanaceae .. 22.2. .eeeeeeee 173 | Potato... 2.000.000 247
Platanus .... 22.20.0000. 00. ce eee 173 pea... eee eee 189
Pleurisy-root... 20.0.0. eee 232 SWeet.. 0. eee 23
Pleuropterus.. 2.0.0.0... 020.2222 cee eee 147 Vine... cee 233
Pluchea... 2.2... eee eee ee eee cece cee eee 283 | Potentilla.......22222. 000000000 176
Plum, Chickasaw........000.000000000.2220. 180 } Potorium........ 2.200.000.0000 0 02 ceeeeee 177
Wild... ee eee eee 180 | Potomac Side Naturalists’ Club.............. 13
Plume-grass 0... 0.2. cece eee 66 | Potomac Valley region, flora of....0.......... 17-18
POA... eee ce cee ee cece cece cence eee 87 | Poverty grass. ............... cece cece eee ecee 82
Poaceae. 2... cece eee ee eee 66 | Prairie willow.......... whee cece een eee cneee 134
Podophyllum... 2.0... 0... 160 | Prenanthes....... tee eee e cece tec ececenenee 265
Podostemaceae.. 2.22.20. 2 02 ce eee Wl} Prickly ash... 2... ee 192
Podostemum... 2.0... 02.20.00 ce cece ccc e eee 171 lettuce... eee cece eee 266
Pogonia ......... 2.2... e eee eee ee 129, 130 1 211
TOSO 2 2 eee cee eee eee ees 129 1900) 9) 8 162
Poinsettia... 2.0.0.2... eee eee ee eee eee 197 | Primrose, evening.................2-00000--- 214
Poison hemlock ............2 2200 cece eee ecee 219 family... . 2.0.2. eee ec cece cece cece 225.
IVY 2.0 eee eee cece ee ge eee 198 000) (:) Ores eseceeee 208
SUMAC .. 22. eee eee ee 198 | Primulaceae............0022 000.0. c ee eee 225
Pokeweed 2.20020... cece eee ee 150 | Prince’s-feather...........00000000.002 000000. 146
family... 2.0.0... e eee eee eee 150 | Privet.... 000.0002. eee ccc eee ce eee 228
Polemoniaceae........ 0020000000002 2 0. 285 | Proserpimaca......... 2.6.0. eee eee ee 215
Polemonium.....2....00¢0.0.202............ 235 | Prunella... 2... cece cece eee 243
Polianthes........0..0.0000.00.0002202.0-..-.. 125 ) Prumus...... 2.2.22. 0 20. c eee eee cece eee 179
Polyeodium........0..0.00.00.002.0......... 224 | Psederd... 2.2... cee eee ee eee 201
Polygala....2..2.2.02. 0000000000002 00 198 | Ptelea... 2.2.22. eee eee cee eee eee 192
Polygalaceae... 2.22.22. .0 000.2 198 | Pteretis. . 2.0.0.2... eee cece cece cee 54
Polygonaceae.... 2.0.2... ..00000.00020000000. 144 | Pteridium.......... 0.0... 00 02 54
Polygonatum..............00.2002.0002.000-. 123 | Pteris...... 02... eee ce ae 54
Polygonum...........0.02..000002000... 145,146,147 | Ptilimnium............ 00000002 0000-020002.. 219
Polymnia........2.0 2.0202... 0 2c 285 | Puecoon, hoary..............2.00.0..6 00000 238
Polypodiaceae... 2.2.2... 2 02 53 | Pueraria...... 2.2.0.2. 190
Polypodium...........0.000002000002000.00.. 56 | Purple fireweed.. 2.2.2.2... 0.0220. c ee eee eee 213
Polypody ..-.........20.00.00200 2002-000 56 foxglove.. 2.2.2... e eee cece nce eee 253
STAY... 2. ee eee eee eee 56 loosestrife. 2.2... eee e eee 212
Polypremum............2..2....02...0...2.. 228 milkweed. . 2... ....0. 0.022 e eee 232
Polystichum...........0.22.00..0000..0002.. 55 orehis. 2... eee ce cece eee 129
Pondlily, yellow...........0002.0000..0...2... 155 sneezeweed............. 22022 e cece ee cece 290
Pondweed........... 2222.00. 00.0 .c0e eee e eee 62 0) Os 86

INDEX. 323
Page. Page

Purplish cudweed.............-.---++-+++5+- 284 | Rhynchosia........-..2...0 222. eee ee cee eee 190
Purslane. .........-2.------ cence ee eeeeeeeee 150 | Ribbon grass...........2..2..-22220.002022-- 81
family.............. cece ce eee eee eee eeees 150 | Ribes...........222. 2.22222 e ee eee eee eee eee 172
milk..............-..... vaceceeececeeeees 195 | Rice cut-grass.........2..0.2222020.202220055 81
speedwell.........2....2.2-2-0- eee eee we. 252 Wild. 2... cee eee eee ee 81
water........- eceeeee coe eceneeeeeseeee 213 | Richweed..............-0......022 20-22 eee eee 143
PuSSy-toeS..........00 00-022 e ee eect ee eee 283 | Ricker, P. L........-....-..-. be ceeeeeees 13, 14,15
Putty-root....... cee e eee e eee cee e ee eeee 132 | Ridan.............. 2.2 eee eee eee ee eee 287
Pycnanthemum. . 02.02.6000. 0 2c 245 | Rippleweed..............-. Loc nee e eee ceeee 171
Pyrola. ..........2.--2.-% Pen ageseeenececceees 221 | River birch.............. 2-20-0022 eee ee eee 137
Pyrolaceae. .........2..2.22220-0- 222 e eee 220 club rush. ....-.....-2.0.02222 ee eee eee eee 97
PYTUS . 2.2.0.2... -20-0 0-22 eee eee eee 177,178 | Robinia..... 20... eee eee eee eee eee 185
Quack grass. ........2.....00 20-62 e eee eee eee 90 | Robin’s plantain...................22-2.0-4- 282
Quassiafamily..............-.--.--------555- 193 | Rock chestnut oak. ..-. cece eee eee eee eee 140
Quercitron....... cece eee eee ete eee eee eee 140 CTOSS. 0.2.) ee cee eee eee ences 168
Quercus... 2.2.2.2. 22022200 eee eee 138 | Rocket, dame’s...-.......-...0002eee eee eeee 167
Quick grass......... 0.220220 2 2 eee eee 90 larkspur......2......2.2-2- 202 ee eee e ee eee 157
Quitch grass......2.........-000 20202222 e ee _ 90 | Roek-rose family ....,....---2---22--22 2-206: 205
Quillwort. .....-....--2+-.0 eee eee eee eee ce. OO} Roripa.. 2... ccc cee cece cee lene cee eee 166
family... 22.0.0... 0 22 cee eee eee eee eee B80 | Rosa... 2... eee eee eee ee eee eee 174
Rabbit-foot clover...............--.2+2+5555- 184 | Rosaceae... ...cccccececececececececececeucuee 173
Radicula........... 2.0... e eee eee eee eee 165 | Rose, J. Novi... cece cece ence cence eee eees 14
Radish... 2.00.0... 222-0222 eee eee eee eee eee WO |) Rose... 22. .eceeeeceecee ce eee eee ee eee 174
Ragweed, common........-..-.-2--+++++0-+- 268 climbing. ..............0.2 22000022222 e ee 174
family..............-2 22-5262 e eee eee eee 267 C6) ceeeeccwcunnaee 174
great... 20.22.22 ce eee eee ee eee eee eee 268 family ............2..0200- base eceecneeees 173
Ragwort, golden...........2.0..----.2++--0-- 291 MallOW ..... ee ccccceccecceccecceceecsee 204
Raimannia..............--- 2-22-22 eee eee eee 214 of Sharon. ........2-2.-cececeececeeceeeee: 203
Ramie................. 2-2-2 e ee eee eee ee eee 143 pogonia............222. 0222 eee eee eee eee 129
Ranunculaceae...........0.. 0060-2 eee eee ee 156 SWAMP... eee eee cece eee cece e eee 174
Ranunculus........ 22.20.2222 eee eee eee 158 | Rosen, H.R... ee ee eee eee eee eee 14
Rape.........--.----- Lecce eee eee eee ee eeeee 170 | Rose-gentian..........22-...-22-22-2 eee eee 229
Raphanus.............2 222222 c cece eee eee eee 170 | Rosin-weed...........22... 0-222 ee cece ee ee eee 285
Raspberry, black. .............-----22---2+-5 175 | Rotala.... 22.22 eee eee eee ee eee 212
flowering... 22.22.2020 cece eee eee eee eee 175 | Rough bedstraw............----..---2------- 258
Rattlebox........2. 22-2020. e ee eee eee eee eee 183 hawkweed...... cece cece eeeeee ceeeeeeeees 267
Rattlesnake grass............20-2-0.0e2e eee ee 89 | Rough-stalked meadow grass...........-...- 88
Rattlesnake-root. ......2.....-2 0-202 -2-e eee 265 | Royal fern......... 2.20202 oe ee eee eee eee eee 52
Rattlesnake-weed. ......2.-....02-00.-0-052- 267 | Rubiaceae........ cee eee cece Lee eee eee eee eee 257
Red ash.........----2--00 0220020 e eee eee eee 228 | Rubus.............0220. 0222 ee eee eee eee eee 174
birch... 0.22. 137 | Rudbeckia...............-- 222000 e eee eee eee 286
Cedar... 0... eee eee eee eee eeee Gl | Rue... 2. eee eee eee ee eee eee eeee 192
CloVer. 0.2.22 eee eee eee eee eee 184 ANCMONC.. 2... ee eee eee eee eee ee ees 157
Currant... 2.62.22 ee eee eee eee eee 172 family... 2.0.2.2 ee eee eee eee eee 192

C0) 0 141 Ruellia.. Lee eee ee eee eee 256
fESCUC. 2... ee eee ee eee eee eee 89 | Rulac.... 22.2... eee eee eee eee eee 200
NAW 2.2... eee eee eee eee eee eee 178 | Rumex.............-22. 0022-2 ee eee ee eee eee 144
maple...........--- 26-2 eee eee cece ee 200 | Running pine............----..----------+-- 59
milkweed........-2......-2522022-0-005- 233 | Rush........2.. 22. cence eee eee eee eee eee 117
mulberry......... 02.20 ee eee eee eee i4] COMMON.........2.0 22 ee eee eee eee eee 118
OAK... ce eee ee eee eee 140 family.........22...0220-.2 2022222 e eee eee 117
Hedbud.........-2.-- 220.2. cece eee eee eee 180 NUt.. 2... eee eee eee eee 99
Redhead grass.............2..2020 0-020 -p eres 63 path.......... 20... e eee ee eee eee eee eee 118
Red-seeded dandelion......-. Lecce eee eeeeee 265 river club. ........... 20220-2002 e eee ee eee 97
Red-stalked aster..........-...0.--25--2--05- 281 Spike... 2.2.2... ee eee ee eee eee eee 95
Reed........--..+- cee e cece eee ee ceeeeeeee 86 toad... ce ee eee ee eee ee eee 118
Canary QIassS........ 6... eee eee eee eee ee 81 | Russell, P. G...........--2. 2-22-20 +222 - ee ee 15
Reed-grass. ......--0.0 0-20 e eee eee eee eee ee 84 | Ruta............0.. 00222 eee eee eee eee 192
WOOd... 22 eee eee eee eee 83 | Rutaceae.............--2.-----2 2222-22 e ee eee 192
Rescue grass... 2.2.2.2... 2220020 e eee eee eee 90 | Rye@..... 22... eee eee eee eee eee eet eee 91
Resurrection fern. ..............---4-645 eens 56 BIASS. 0.6. eee eee eee tenes 90
Rhamnaceae. ...........-2- 02. ee eee eee ee 201 wild... 1.2.2.0... 2.0 eee eee eee eee eee 91
Rhenia.... 02... o eee eee eee 212 | Rynchospora.........-...----+-+ee2 eee eee eee 98
Rhode Island bent...............-.-.------- 83 | Sabbatia........2..... 0.00. 229
Rhododendron............-....0--2--0020055 223 | Safford, W.E........ pecs eereceeeneeecenened 14
RUS ..... 2.2 tee 198,199 | Sage, lyre-leaf.. 2... 2-022... 2-2 e ee ee ee eee eee 244

324 INDEX.

Page.
Sage, nettle-leaf.............-- 00 cee eee eee 244 | Scrub chestnut oak.............0000000000-..
Sagina. ..... 0... eee eee eee ene 158 PING... eee cece eee eeeces
Sagittaria......... 0... sees e eee eee eee eee 65 | Seutellaria..... 22.0... c cece ceee eee eee ees
Sago pondweed................. ccc cece eee ee 64 | Seaman, Wm. H..... 2.2... e eee eee ee eee ee
St. Andrew’s cross.............22. 0.02 eee eens 204 | Secale... le... cece eee e cece cence ceee sees
St. John’s-wort............0200. cece eee eeeee 204 | Sedge, broom............0 0. ccc cce cece ceccee
COMMON. ....2- 22... ee eee eee eee eee eee 205 family... 2.22.0... e cece ee cece eee eee eee
family.........2.... 222 eee eee eee eee eee 204 | Sedum... eee cece cee eeeee eee
MALS... 2... ee eee eee eee eee eee e eee eeee 205 | Seed-box........ 0... eee e eee eee cence eee
shrubby..........2....22222 eee eee eee eee 204 | Selaginella family...............0000...0000.
St. Peter’s-wort.. 2... 2.2.0... eee eee eee 204 | Selaginellaceae.......00.. 00.02 e cece eee
Salad burnet.... 2.0.0.0... 02. e eae ce eee eee 177 | Seneca snakeroot........2........0022202----
C00) 9 6 261 | Senecio. 02... eee ee eee eee eee ee
Salicaceae.. 2... ee eee ee ee eee eee ee eens 132 | Senna family .........0 00.00.00. e cee eee
Salomonia. oo. cee ec ccc cece eee ee 12: A 0 ce
Salsify............222.2 222 eee eee eee eee eee 204 | Sensitive fern..... 2.2.0.2 ccc cece eee eee eee
Salsola... 2.2... e eee eee eee eee eee eee eee 148 PCO... ee eee eee eee cece eee cee
Saltwort..........02....2.02. Greece eee e enna 148 | Serapias... 2... eee cence ee
Salvia.......... Lecce cece een eee e een eeeeeeee 244 | Sericocarpus.. 2.2.2... 0... cee cece cece cece eee
SambucuS......-...-...... cece eee e cece eee eee 261 | Serviceberry.......... cee eee e cece ee ences sae
Samolus...........-0-0- 0-22 e eee eee eee eee eee 225 | Sescli... sc... ccc. cee cece cee eeeceeeeeeecece
Sand blackberry..............0-2.2-220-0000- Oe
QTAPC. 6... eee eee eee eee eee eee 202 | Setiscapella..........0. 20. c cece cece eeeceeee
SPUITY. ..-.. 22-222 eee eee eee eee eee i5l | Shadbush.. 2.2.22. 2.... cece cee ceeeceecee cece
VINE. cece cee eee ee 231 | Shag-bark hickory seen ence eee cence eee eeaes
Sandalwood family.................2.2...... 143 | Sheep fescue.......2220 2. cee cece eee eee eee.
Sandbar willow. ...........2....-022....0208- 133 laurel... 22... eee eee cence eee cece
Sand bur. ...... 2.6.60. 2 eee e eee eee eee eee 80 S00 i
Sandwort............. 2222222222022 eee eee ee 153 | Shell-bark hickory............. 00002 -000000ee
Sanguinaria.. 2... 2. cece eee 162 | Shepherd’s-purse ...........0..0..0eee eee eees
Sanguisorba.............20.-02ee eee eee ee ee W77 | Sherardia......2......0 0c c cece cece cece ee cee
Sanicula... 2.0... 2. eee ee eee eee eee 217 | Shicld-fern, marginal..................200...
Santalaceae.............2202 0 cee cence ee eeecee 143 | Shingle oak... 22.2... eee cence eee
Sapindaceae............ 00. eee e eee eee eee eee 201 | Shining bedstraw..........2....000.0.00000.
Saponaria.... 02.2.0... eee ee eee eee ee eee 155 | Shinleaf....... 0.0000... eee ee ce ceeecc ee eee ee
Sarothra. ....2. 0.2.2.2 eee eee eee eee ee eee 205 family... 2.2.2... cc. eee eee eee cecceceeees
Sarracenia... 2.2... 0.2.0... 0 ce cee eee eee eee 170 | Shooting star............ cece eee eee eee eee
Sarraceniaceae. ..... 2.2... 022. e eee eee eee eee 17 Siberian crab apple..........2.......200.000-
Sarsaparilla, wild..........2..2....222....22- 215 | Sickle-pod..........2 2222... e cece ecccececceee
Sassafras... 22.2.2... 2 eee eee eee eee eee -- 162 | Sieyos........... 2. cece eee eee ee cece eeeeee
Saturejd .. ccc cence eee e eee eens 244,245 | Sida... eee c cn ew cece ee cececceces
Saul’s 08k... . 20. e cece eee cee cee cece cece eee 140 | Silenaceae.............02 0.0. e eee eee eee eee
Saururaceae........ 22.222 cece e eee cence eee 132 | Silene.. 2.22... eee eee eee cee cen ence ee
Baururus.. 2... eee eee 132 | Silky willow............ 2... ccc cece cece cence
Saxifraga....... 2... cece eee eee eee eee ee eee 172 | Silphium..... 2.0.2... e ee eee
Saxifragaceae..........2....-02222.0202222-0045 171 | Silver aster........ 0.2.2 e eee
Saxifrage.............-.2--2 2-22 eee eee 172 Maple....... 2... eee eee eee eee cece neces
family... 0.2... eee eee ee ee ec ew aces 171 100) 9) 2)
Scandix........... ween cance eee e ese ee cee eeee 215 | Silver-rod............. ce tence cece ec eeeeeeee
Scarlet oak... 2... eee eee eee eee 0 | Silver-weed........... 20... cee e eee eeeeeeeee
SchizachyTivM .. 0... ccc cceeeeceeenenes Seeeeeee 72 | Silvery spleenwort..........0.c.cceeeeeeccees
SUDZONUS... 2.2... eee eee eee eee eee 71 | Simaroubaceac.............. 000 cece cece eee
Schizacaceae. ..... 0... e eee eee eee 53} Simapis..... 00.2.2.
Schmaltzia... 2.2.2.2... eee ee eee eee eee 199 ] Sisymbrium .............0.0200.000000 000008 166
Schollerd... 02... ec een eee 17 | Sisyrinchium.........00.......000020. 22 eee
Scilla... 2.2... eee eee eee 120 | Sium..... 2. eee eee
Scirpus... 2.2.0.2... 0220200222 95,96 | Skeels, H. Co... 0...
Scleranthus......... 000.000.0002 c eee eee cece 151 | Skeleton-weed........000000. 0c eee eee eens
Scleria... 2.0.20... 0.2.2 eee eee eee eee 99 | Skulleap....... 2.2... eee eee eee ee eee
Scorpion-grass........0-2-..2.222.0.000 2220 238 mad-dog..... 2.2. . eee ee eee
Scoteh fir. ..... 2.22200 eee 61 | Skunk cabbage........0...0000 0022 eee eee
thistle... eee eee cee eee 292 | Sleepy catchfly.... 2.20.0... eee ee eee eee
Scott’s spleenwort....-..2.... 000000000000... 55 | Slender violet. ............22020000.0002000.
Scouring-rush........ cence eee e eee e ee 58 | Small cane... ..........0...020 00200002222
Scrophularia............0...02220000000 000000 25 Smartweed..................... elec eeecnanes
Scrophulariaceae... 2.2.20 0000000000000 eee 248 dodder.. 2... eee eee eee

INDEX. 825
Page. Page
Smilacaceae.. 2.2.2.0... ee eee ee eee eee en eee 124 | Spiraea ..... 2... eee eee eee ee eee 174, 175
Smilacina... 2... eee eee eee cece cece ee eeeeee 123 | Spiranthes........ 0.0... cece eee ence eee 130, 131
Smilax. .... cece eee eee ee eee cence ee eeees 124 | Spirodela...... 0c eee cee eee ee eee 115
family... 2.2.2.2 eee eee eee eee eee we eens 124 | Spleenwort.............2... eee eee eee eee eeee 55
Smith, C. Pe... eee eee eee eee 14 Os 56
Smoke tree... 2.0. - cece c cece cece cece eeeeeeeee 198 C2) 60 6 56
Smooth aster. ........cceccceesceceeeeeceeee= 281 maidenhair. .. ....--cecccecececccccccccee 56
winterberry.......-... eee cece ee eeeeeee 199 mountain............0. cece cece cece coeee 56
Snakeroot, black..... weet eee cence eeeeee eens 156 ST (8D
bl PPT eTITTT TTT TTT TTT eee 217 silvery necececcace ceucececccucececuce 56
button. 2. eee eee eee eee eee ee eee 217 Sporobolus cece ce cece cenecucucecwcucucenecce 83
SOMOCA... +2. 220eeee renee es eeeee ee eeeeeers 193 | Spotted pipsissiwa..............ce ce ceeeee ees 221
ViIPBIMIB. 12.2 s eee oeeeeeeen sree cee ereeees 143 touch-me-Not.... 2.2.2 .0.02eseeeeeeee eee 201
snene eee PPT ee Seer ee ee eee e ee ere reer a Spring beauty.........2-2.eeeeececececececes 150
rotereeesereccresscecces patttssses 1 tee errs C:)
DUEDIO.. we eseceereercenneeeeecnsececas eee 290 TIS. eee eee ceeececeeeseceeeeeceeeeeees 126
Snowberry Tet rteseteeererseeeccces secs se cces ho Spurge, caper..............2 ee ceeee eee eee eee 197
To caresesceeeessecesecssacceccscccs CYPTCSS. 6... cece ewe eee cee cceenewneceseeee = 197
Snow-on-the-mountain.............-----.--- 196 a 194
SNOWY CAMPION........-0.seeeeeeeeeeee secon 154 flow ering Tose ee serereceeeeseseeereessess 197
Solanaceae..........2.eeeeeeeeeee weeeee veoeee 247 | ge -
Solanum 949 puny aa tee e eee en eee eee eereeneseneeceeee 151
Co eee esse cescceccwccegcrsrrssssssess ; SANG... cece eee ee cee eee cee eee cece cee 151
D0 te 206
verretesess S TOO. cece ee cecececececeeececeeeceees D5!
Solidago.......2sccsececscecceseececeeaeees 276,278 | Toot tp
Solomon’s-seal......0......0202eeeee eee ee ee ee 123 [Mh Suri ttsesssssscssseccscaecescsscsg ence:
false 123 Squirrel COrM. 02.0... ccc cece cece cece ees ee anes 163
Sonchus... ee 965 Squirreltail grass... 2.2.2.2... cece eee eee eee 91
SonchuS........0.. cece cece eee ee cece ence eee StachyS.....0..0..-..cesssececesececececece. 9243
Sophronanthe. ........-....000-00e eee eee eee 251 . .
Sorghastrum 79 Stagger-bush..............2.20eee se eeeeeeeee 223
Sorshurn Tose esesserecsereerersesesseses 79 Staghorn sumac. ................2.0. ee eee eee 198
Soreo Terese esses essere eeesesesssesseess 7 Standley, Paul C............2...020 ee eee eee 14
Sorrel, sheeP--.. ss sccceeeececeseeeeeeee. 144 Staphylea.... cc. eee eee eee eee eee e eee 200
_ Staphyleaceae............ 2.2.2. e eee eee eee 200
Soulard crab apple... .......2-...2-eee eee eee 177 .
Sour Cherry..... 22.2.2 eee ee eee eee e eee eneeeees 180 Star of Bethleham......---+----+e-+++eree2- 122
Sow thistle... 2... 0... eee ee eee eee 265 ceeweee Toners reese eeeseseeeseseeesess. a
Spanish needles........-.c-seceeeeeeeeeeeees 289 cucum as 26
OAK.....eeeeeeseceeeeeeeeeeceeeceeeeeeeee 149 |__| thistle........-++seeeeeeeeeeeeceeeeeeeees 293
Sparganiaceae..... ween cece eee ee eeseeeeeees 62 Staneress wortta scr eesesesceecsceeeecse sce ess 125
Sparganium..............ssesecceececeeeeese 62 Water..........4 cece cece ence eenee eee eees 117
Spartina.......0.--..sseeecceeeeeceeececeeeee % Starry campion..................00222 2 eee eee 154
Spathyema.......2.00.eeeeceeeceeeceeeeeee 4 Starwort....... 2.00... eee eee eee eee eee eee 152
Spear grasS......2.0eceeeeeceeceeeceeceeeeeee 2 water.......-....2- eee ee eee eee ee eeeeeee 197
Spearmint cece cee eeeccuncceceeeccsceececesece 246 Steele, E.S.........-- we eee ee eee eee eee 13, 15
Species, method of treatment................ 1g | Steiromema.........---------++ eee e eee ceeecee 226
Specularia.... 0.0... cece cece cece eee ee eee ee eee 262. | Stenanthium..........+..-sseeeeee ee veeseee 120
Speedwell cece mene nccccecccucacececuceseeeces 952 Stenophyllus street tater es esees BB eens serene 96
common......... vce cucacecacecececucecce 959 Stitchwort...........--. cece cece eee cee ee eee 152
COPD oe cc ce cececccccececucuececccecececes 959 | Stickseed..........--------- cece eee e eee eee 237
GeTMANder.........22ececeeeeeeececeeeeee 952 Stink TASS. .....22222.6-- cece ee eee eee eee eee 86
ivy-leaf... 2.2... cece ee ee ee cece eee eee 252 | Stipa... 2-2... e ee eee eer et eter eter eres 62
MATS. . 22. ee ee eee ee ees ee eee ee eees Leeeees 252 | Stomoisia.....-.....+2+2- 0.02 see esos eee 255
purslane ne cccacececaee aca ceeecececececee 252 Stonecrop ee eee ee ee ee eee eee 171
thyme-leaf......02.0.0c0cecececececece ees 252 ditch. ........---+--2 02 ee eee ee eee eee eee 171
Spergula........c0seeeeeceeeeeeeee ee 151 three-leaved ........00 200000202 171
Spergularia........2...-. ; ASL Strawberry bush.......-2.....-.2.4200eee eee 199
Sphenopholis........- cece ence eee e ee a 84 nse werete ee cerscecererorororcresecsess n
Spice bush,............-....-2-2-.-2--22-005- 162 wild... i
. spies (I 0 0.00 Cree ‘
Spider-flower. ......- +--+ .+-eeeeeeeeeec sree WO | striped gentian......... cece cece ceeeeeceeeees 229
Spiderwort seer eens rere settee ree tense teres 116 Strophostyles.........2.--22-222eeceee cee e eee 190
; family se teceseeeeneaes sateen seen eee e esse 115 | Struthiopteris. ..............000202e eee eee 54
Spigelia............ ween eee e entree eet eee 2B} Stuntz, S. C..... 2. eee eee cece cece ee eee ees 15
Spike rush...... 2.6.6. 222 eee seer eee ee eee 95 | Stylosanthes.........2.22020202eceeeee eee eees 185
Spikenard...... been eee eee eee ceeeeee 215 | Sugar maple............2-.-...--- cece eee eees 200
Spiny amaranth..............-.....---.-.--- 149 | Sumac...... 2.2.0.2. e eee eee ee eee eee eee eee 198
cocklebur...........2-2...---- seeeeeeeeee 267 black. 2.2.2.2. eee eee ee eee cee eee 198
Spiny-bur..............22.. 222-2222 2 eee eee 285 dwarf... 2.2.2.0... ee eee cee eee eee ee ee 193

326

Sumac family.........0.0...0.000.00.0...202.....

fragrant... .

Summer grape...... Reece cece nw ae cetera wennes

Sundew........

Sundrops.......
Sunflower......
common...

ee ee ee ae oe

ee ee ee ee as

SWAMP. 22.222. cece eee cep eee ees

Swamp azalea..
beggar-ticks

goldenrod. .

loosestrife.......2.02.0.. 00.2002. eee ee eee

lousewort...
mallow... ..

vernal grass

william.........00.000.00. 200200. c cece eee

william, wil

06

william catchfly..............00000.02.22.
Sweetbells............0.0.0.0 200.00 ccc ce eee eee
Sweetbrier..... 2... ...0000 00.20.00 cee eee eee

Symphoricarpos..............-.....0000.00.-

Symphytum...
Symplocarpus. .

Syndesmon............. 020... ee eee eee eee
Synonyms, citation of............2.0.0.02...

Tald blackberry
cone-flower.
goldenrod..
oat grass....
tickseed ....

INDEX.
Page.
198 | Tanacetum...............2....
199 | Tansy........2.2.0.2220..00002-
198 | Tapegrass.............2.....--
198 family.....0....02.2220....
198 | Varayacum.................2--
202 | Taxodium.....................
170 | Tea, New Jersey
170 | Tear-thumb.,.................
214 | Teasel......0....02.000202000.0..
286 family.............2.2.22-.
287 Tecoma... 22.22.
287 Tephrosia... 0.000000. eee ee
223 | Teucrium.....................
289 | Thalesia.......................
175
144. | Thaspium.........02.0.0200....
278 | Thistle.........0000..200220...
212 Canada.............2...6-.
254 common...........-.....--
204 musk.... 22.2... 2.02... 000-
233 pasture. .2 2.2.2.2... ee eee
135 Scoteh..... 2.22.2... eee eee
174 SOW 2.2 ee eee ee
287 Sar... eee eee eee eee
292 swaMp......2.....22..-...
140 Virginia. 2... 0.0... e eee.
165 | Thlaspi........222..2.20220002..
220 | Thorn, Washington
220 | Thorn-apple...................
161 | Three-seeded mercury
137 | Thyme, basil.............22...
180 creeping..... 2.2... eee eae
218 | Thyme-leafspeedwell
183 | Thymus..............-.-..+..-
135 | Tiarella......2.......2.0....02.
114 | Tiek trefoil...........222..0...
173 | Tickle grass............. seeeee
221 | Tickseed, tall..........22......
233 whorled................---
81 | Tidestrom, [..................
1o4 | Tigerlily.........2.......2222.
235 | Tilia.....2. 22.2.
154 | Tiliaceae.. 22.2...
223 | Timothy.......2.0....0........
174 Timiaria. .. 00. eee eee
208 | Tipularia...........2..........
278 | Tissa......2....-222222.--.-2--
173 | Tithymalopsis...............2.
173 | Tithymalus.........0.........
200 | Toad rush.....................
259 | Toad-flax, bastard
238 blue... 2... eee eee eee
Id | Tobaeco, Indian
157 | Tofieldia.....2.........0.0.....
16 | Tomato..........2.....20.20..
291 | Tooth-cup................2.-..
72 | Torilis..................... sees
227 | Touch-me-not, pale
61 spotted. ...........22......
218 | Tovara.........20......202.. ..
150 | Toxicodendron................
175 | Toxylon..................022..
286 | Tracaulon..............2.22...
278 | Tradescantia.............2....
85 | Tragopogon.....-.............
288 | Trailing arbutus...............

Page.
290
200

66

66
265

61
201
17
202
202
254
Is4
241
2556

TYAPO. 2.22 eee eee ee eee eee
Trapaceae.......... 0222. e ee eee eee eee eee

Trautvetteria.............-2----- 22 e eee ee eee

Triadenum................24----- eee re eee
Trichostema............---------0---0e2eeee
Tricuspis..... 2.20200. 0.2202 eee eee eee ee
Tridens......-...222 222-2 eee e eee eee eee eee ees
Trifolium. ......-....... 20.2002 22 eee eee eee

Triphora....-......-.-.-2- 2.202222 eee eee cere
Tripsacum.... 2.2... 2-2-2. 2- 22 eee eee eee eee
Trisetum...........22....2. 222222022 e eee eee
Triticum... ...........00.-2 22220 eee ee eee
Trout lily..... 22... 2222.2. 22 22222 e eee eee eee
Trumpet creeper.........-----2-+--220- eee

honeysuckle. .........---.---------++--+-
Tsuga... 2.22.2 ee eee ee eee eee ee tee
Tuberose........-.-----..------ we eeeeee eee

Tulipa...... 2.2... 22.-. 2.22.2 e eee eee
Tumble mustard...........---- seccereeetere
Tumbleweed......-.. cece cece cece eeeeeeeeeee

Twayblade.............-2..-2 202-2 e eee eee eee
Twin-leaf. ....0.00.0 000.0. - ee eee ee eee eee eee

Umbrellawort.........-.-----2----eee ee eee eee
Unicorn plant........-.-.-.+---+-+-- ce eeeeeee
Unifolium...........0..... 02-22 e ee eee eee
Uniola...............0-202 222-2 eee eee eee eee

Urticastrum. ......-....-2-22- 0-2 eee ee eee
Utricularia........-..-..------------ weeeeeee
Uvularia..........-22 2222-2222 eee eee eee
Vaccaria........ 2-22. ee ee eee
Vaceiniaceae....-.-------22- 2-2 eee eee eee eee
Vaceinium........------2 22-22 ee eee ee eee eee
Vagnera..........-- 22-22 eee eee eee eee eee
Valerian. ..........0...-2----2 2-2 e eee eee eee

family......-...-.------ 2-2-2202 - eee eee
Valeriana..... 2-22. 22-22 eee eee
Valerianaceat..... 2-222... 22.2 eee eee eee eee
Valerianella..............-2--020 eee ee eee eee
Wallisneria.... 2.2... .0.---20 0. eee eee eee eee
Vallisneriaceac. .-.....-..-------- eee eee eee eee
Van Eseltine, Florence L........-........---
Van Eseltine, G. P......-.---- Lene e eee eee ee
Vasey, G@Orge..... 2.2. e eee eee ee eee eee ee eee
Velvet grass. ... 2.2.2... eee ee eee eee ee eee eee
Velvet-leaf.. 22.2... e eee eee eee eee eee ee eee
Venus’s looking-glass.......-..------+--------
Veratrum... .......-2 22. eee eee eee eee eee ee
Verbascum..... 02... e eee eee ee eee ences

INDEX. 327
.. Page.
214 | Verbena................ 220-0 eee ee eee eee 239
214 | Verbenaceae..........--.------- eee eee eee eee 239
158 | Verbesina.............-..----+-+ eee eee 286, 287, 288
193 | Vernonia............0-... 0c eee ee eee eee eee 273
184 | Veronica....... cece cence eee twee eee eeeeee 252, 258
185 | Vervain, bluc.....-...--.-----------++ eeeeee 239
205 European... .....--202-se eee eee eee ee eres 239
241 famly..... 2-2. ee eee eee ee eee ee eee e eee 239
86 narrow-leal..,..-.....------202eee reece 239
86 white. 0.002... e eee eee eee eee ee eee ee 239
183 | Vetch.......... 2.0 eee eee eee eee eee eee eee 188
124 French... ......---- 2c e eee eee ee eee eee 188
260 hairy... . 2.22.22 eee eee ee eee eee cece eee 189
130 Milk. ..... 2. eee eee eee eee ee eee eee 185
71 | Viburnum..........02.-- 2-2 eee eee ee ee eee eee 260
84 | Vicia... 0... eee eee eee ee eee eee eee 188
Q1 | Vigna... 2.22.22... eee eee eee eee eee eee eee 190
122 | Vilfa.. 2.2.2... cee cece eee eee eee tees 83
234 | Vinea..... 2.2... eee ee ee eee eee eee eee eee 230
259 | Vincetoxicum.......-.---..----.-.e eee eee eee 231
61 | Viola... 2... eee eee eee eee eee eee eee 206
125 | Violaceae...........---0e eee eee ee eee eee e tees 206
120 | Violet......---------- cece cece eee cece eeeeces 206
161 arrow-leaf....-..--.-----eee eee cece eee 209
120 hird-foot........------0-ee ee eee eee eters 208
167 Britton.......-----------ee cece eee cence 208
149 butterfly .....------ 2-22 ee eee eee eee eee ee 211
121 CCAM. . 22. eee ee eee eee ee eee eee neces 208
170 UOQ.. ce cece c eee e eee cee eee eee eeeeeteees 208
114 dog-tooth. ....-..--------+--eeee eee eee eee 122
250 COWNY .. 22-222 eee eee ce eee eee eee ee eee 210
131 English. ....-.-.----- 2-02 esse eee renee 208
160 family... ......2220+eeeece cece ee eeeeeeeee 206
62 OTCON.. 2.2 eee ee eee eee eee tenes 206
62 lance-leaf........--------eeeee cece eee eee 208
140 PANSY... 26... eee eee eee eee eee eee eee 208
140 primrose... .. cece ee ee eee eee eee tence 208
149 slender... 2-02-02. eee eee e eee eee e eens 210
254 white... 2.0.22... -0- eee eee eee eee eee 208
123 wood-sorrel..-....---------+++-+eeeeeer ee 191
87 01) C0) cs 207
o74 | VWiorna.....---------0 eee eee ee eee eee ee eee 160
142 | Viper’s bugloss......-.-----+--+------e eee eee 239
142 | Virginia cowslip........-----+--+++--eee- eee 238
142 CTCOPC! . . 2-2 eee eee eee eee eee eee eee 201
255 mallow......--------2--e cece eee eee eeeeee 203
120 snakeroot....--...-----e- eee eee eee eres 143
155 thistle......--.. 2... 22. eee eee eee eee eee 292
994 | Virgin’s-bower......------+-+-+-+-eee eer eee 160
904 | Vitaceae.......-..-----. eee eee eee eee eee 201
193 | Vitis. ........-- 2-2. - eee ee eee eee eee ee eee 202
961 | Wahoo. .....--2--2----0. 0022s eee e eres weeeeee 199
961 | Wafer ash...-.....-----.-----0ee seer eee eee 192
961 | Wake-robin. ......-.-----------eee sere eee eee 124
961 | Walking fern.......-..--------+2 eee eee eee 55
2961 | Walnut, black.....-.-.-.-----++-+--2+6-+20+- 135
66 English... ..-.--2----2+e-e eee e eee ee eee 135
66 family...---- 22 ee cece cece eee ee eee eens 135
15 | Wandering Jew......----------------+--+° 115,116
15 | Ward, L. F.....--.. 2-22 ee eee eee eee eee ee 13
13 | Ward’s willow......-....--..0+2e2-2e seers 133
84 | Washington Botanical Society...--....------ 13
203 plant....2-....2-. 20 cece e eee eee eee eee eee 155
262 thorn... .......- eee ee eee eee eee eee eeee 179
120 | Washingtonia........-.----..eeeee eee eee eee 217°
949 | Water hemlock......---.---.----eeeeeeee eens 219

328 INDEX.

Page. Page
Water hemp .................00c cece ee eee 149 | Wild leek... 2... cece cece cece ceccce 121
horehound................220 cee cece cease 246 HiCOrice .. eee cece cece ceeecuccececcee 258
HYSSOP. 2.0.6... eee eee eee cence cece cece cece 251 lily-of-the-valley........000.-. cc ceeeeeeee 128
milfoil.. 2... 2.2 eee cece cece eee eee 214 live-for-oVer. 2.0.00. cece cc cee ccc ceeceeee 171
milfoil family............... 200000 c ccc 214 lupine..... 2.0.2... eee eee ec eecccceeeeees 183
PAPSNIP..- 2-0... eee eee eee eee eee ee 219 madder...... eee ceca cece nce ccnccccaacs 258
plantain. ...... 2.0.2... ec cece cece eee 64 Marjoram............ cece. cece eee eee eee 245
plantain family................202..00.2. 64 MINt. occ ee eee cece eeeeee 2
purslane... .-... 2.22.2... eee eee eee eee 213 ONION... eee eee eee eee eee cence ences 121
Star-grass...... 0.02... ee cece cece eee eee 117 pea...... weet eee news eee e cence eeenaes 189
Starwort..... 2.2... cee ce cece cece cece ee 197 pink... 2. ec eeeeccee cence ee eee 154
starwort family...........00.0...2200005. 197 PUM... 2.2 cece cee eee cece eee 180
WILlOW. 0-2-2. eee ee cece cece eee 256 potato vine....... 2. eee e eee eee eee 233
Water-carpet... 2.22... 2.022 eee cece ee 171 MICO. eee eee cece ee eee eee eee 81
Watercress... 2.22... 2.0. c cece cece cence ceece 166 Lk 91
Waterleaf......2.....-.00. 00 cece cece cece 236 sarsaparilla............0... cece cece eee ee 215
family... 2.22.00... 0. ccc cece eee eee eee 236 SONNG. 20... eee eee eee eee eee eee n eee 180
Waterlily family ...........02. 0020022000008 155 SUPAWDEITY . 0... cece eee ween cee cece eeees 175
White.........0 02.0... cece cece cee ec en eee 155 sweet william. .................00ee cece 235
Water-shield. 2.2.2.0... 0... c ccc cece eee e ee 155 Wandering Jew... .......0....-2.020000-. 116
Water-weed..... 20... .. ccc cece e cece cece ence 66 ED 6 125
Waterwort........2...... cece cece cece ce eeeee 205 | Willow... 2.2... cece cece eee ee cee 132
family...... 2222.22 eee cece eee ee eee 205 1 133
Wayfaring tree... 22.2... 2 eee cece 260 CTACK. 0... ee eee cece cceuceeeceee 133
Weather-glass, poor man’s...............-... 226 dwarf prairie... 2.2... eee 134
Weeping willow................00...2.2020-. 133 family... 2. cece cece cece 132
Wheat... 2.2.2.2... eee cece cece ee OL oak... 2.22... “Lace eee cece ceeeeees seeeeee 139
BTASS 2... ee eee eee cece eee eee cece ee ee 90 prairie... 22... eee eee 134
Wherry, Edgar T. 22.2.2... ....002002 00-00 16 sandbar.. 2.2.2.2... ee eeecc eee cececeeecee 133
White ash... . 2.2.22... . ee eee cece cee cece 227 SUK. eee cece eee ee eee ee 134
campion.....-.. 0.022... e eee cece ee eee 154 Ward’s.. 22... e eee ccc cece cece eee 133
CIOVOD. 2... eee eee cece e cece eee c cece 184 Wate? .. 2c. e eee e ee eeee 256
Fo 2 os 81 WeEDPING .. 2... eee e eee ee cee ee ee 133
jasmine... 2.2.2.2... eee eee eee eee eee 227 White... eee cece eee cece eee 133
milkweed............. 2.0.0... ccc eee ca eee 233 | Willow-herb..... 20... .ccc cc cece eee cccecceee 213
MUIDeCITY..... 6... eee eee eee eee eee 141 | Willow-weed............0000 22. cccee cece eee 146
mustard.......-... 22.2 c cece eee e cece ceeeee 170 | Willugbaea,.. 2 oo. ccc cn cece 275
Oak... 2... eee ee eee ence cece 140 | Winter cress... 2.00... 0. ccc cee cee cee cece eee 168
PING... ee eee eee cece eee 61 | Winterborry....... 2... eee c eee ee eee 199
1910) 8) Ct) 135 SMOOtN.. eee eee eee cece eee eee eee 199
snakeroot......... 02... cece cece eceecceee 27. Wintergreen... 0.0... e cece cece cece eee 222
SUMAC. 2... eee cece e ence cee cn eee 198 family... eee cece cece cence cannes 221
sweet Clover ....2 2.2.22... e cece eee eeeee 183 flowering ...........2.c2 eee e cece cece eee 194
Vervain... 22.2... e cece eee cece 239 | Wire grass..... 2.0.2... cele cece cece eee cece eee 82
00) ) 208 | Witch grass. . 2.0... eee cece eee eee ee eee 77
waterlily......-.. 0... c eee eee eee eee 155 | Witch-hazel....... 2.02.0... cece cece eee nc ee 172
willow.............. cence cece eeeeee seeeee 133 family... 22... eee cece eee cece eee 172
00 161 | Wolffia... 2.22... c eee cece cee 114
White-top... 00.22... ccc eee ee ee eee eee 282 | Wood anemone..............2..02.002eeee eee 157
White-topped aster...........2.......00..02. 278 CS) cs 280
Whitlow grass...........0....ceceeeeeeeee eee 165 DetoNy .- cece eee cece eee ee 254
Whitlow-wort............2.0-00c0cc cece neces 151 FEIN. . eee eee eee cece e ee eeee 58
family...........0...0 0000220 e cee eee 150 lily... e eee eee cee cee cece 121
Whorled tickseed..............0....0000. eee. 288 mint. 2... eee eee e cece eee eeee 244
Wild bachelor’s button...............2...... 193 nettle... .2. 2... 142
bean... 0. eee eee cece eee eee 190 Tee@d-QTass. 2.2.2... eee eee eee eee eee ee &3
black cherry.................0.0 cee cease 180 | Wood-rush................... wees eee eeeeee - 119
black currant.................eceecceee ee 172 | Wood-sage. . 2.2.2... 2c ccc cece eccae cence eee 241
oC) 66 | Woodsia....... 2.2.2... cee ee ccc eececccec cece 56
COMMTCY eee ccc eee ence cece. 237 | Wood-sorrel family ................2-.00.00-- 191
cucumber. . 2.2.2.2... ce eee eee cence eee 262 02) |) 191
Garlic... cece eee eee ee eee 121 | Weodwardia ............... cc cece cece eee e eee 64, 59
ginger. 22.2... eee eee 143 | Wool grass. ..........0..cc cece cece eee eeeeee 98
gooseberry..... 2... eee cece eee cece 172 | Wormseed..........00 0... c cece eee cece eee 148
Indigo... .. 0... eee e cece cece ee eeeeee 182 mustard... 2.2.2... 2... cece eee cece eee 167
tpecac. ... 2... eee eee eee 198 | Wormwood, annual. ................ 00000005 290

INDEX.
Page.
Woundwort......... wee ceceenesercenessenane 243 | Yellow pimpernel]...........eeeeee news eeees
NManthium.........c.ceeeeeees a weneseceeees 267 Pine... ee eee eee cece e ee eees
Xanthoxalis......... ence een cneenenesneccee . 191 pondlily.......... 222. e eee eee eee eee eee
NolismMa........ 2. eee cence eee e ee enee aecceee. 223 sweet ClOVEr.......-.0e eee eee eee ceee eee
NYTidaceae....... ccc eee wee eens en eceeneeee 115 a6 C0) (cy
NTIS. 2 cece cece cece eww eee eeeeeee eeceeee 115 wood-sorrel.........2.---0-- 22 eee eee eee
0:0 1) saeeeeees 125,233 | Yellow-eyed grass........2.--0-.-. ee eee eee
family... . eee cece eee eee ence cere ee eeees 125 grass family. ...... 0... cece ceeeeee ee eeees
Wild... cece eee ewe e ee eee wececeneeeeee 125 | Yucca... 2. eee eee e ee eee eee eee
VarrOW..... 22. cece cece ee ence een e eee eeeeees 290 | Zannichellia.........-...2-- eee eee eee eee eee
Yellow cress........--+.+- eee een e cece eeeeeee 165 | Zanthoxylum. ............ cece eee eee ee eee
crownbeard...... wee eceeecceceeceeeceees pot A: a
a Ee Lr 126 | Zebrina.. 2.2... ee eee ee ence eee eens
foxtail.........2....... ween cece ee eceeeee 80 | Zigzag bladderwort......----....--- scene eee
Tron-wWeed . - 0... cee eee ee ee eee eee eens 287 | Aizamia... 2... ce eee cece ewe ewe eee ee eeces
JaSMINe.. ... eee cee eee cece ence ne eens 227 | Zizia. 22... eee eee eee eee eee eees
lady’s-Slipper........cccceccccsccesceseee 128 | Zygophyllaceae.............-..- eee eee eee eee

O

Contr. Nat. Herb. Vol. 21 PLATE |

PAINT BRANCH.

a <1

:

DRIVE NEAR PINEY BRANCH, ROCK CREEK PARK.

Contr. Nat. Herb., Vol, 21. PLATE 3

a

NORTHWEST BRANCH.

Contr. Nat. Herb., Vol. 21. PLATE 4.

DIFFICULT RUN, LOOKING OUT UPON THE POTOMAC.

Contr. Nat. Herb., Vol. 21. PLATE 5.

A Rocky GORGE IN DIFFICULT RUN,

PLATE 6.

Vol. 21.

Contr. Nat. Herb.,

‘sTav4 Lv3¥5 MOTB OVWOLOd SHL

Contr. Nat. Herb., Vol, 21, PLATE 7.

AN OLD CHANNEL OF THE POTOMAC BELOW GREAT FALLS.

Contr. Nat. Herb., Vol. 21. PLATE 8.

A. THE CHESAPEAKE AND OHIO CANAL BELOW BROADWATER.

B. GREAT FALLS FROM THE VIRGINIA SIDE.

Contr. Nat. Herb.,

Vol, 21.

—r,

2 SL,

PLATE 9.

THE HOME OF SUCH SPRING FLOWERS AS SPRING BEAUTY,

WooDS ALONG THE FLOOD PLAIN OF CABIN JOHN RUN IN APRIL.

TrRoutT LILy, AND PEPPER-ROOT.

PLATE 10.

Vol, 21,

Herb

ontr. Nat.

C

“ONNOYD3AYOY SHL NI SADGAS YSHLO GNV SNdYIOS HLIM ‘3SX¥AQ YV3N HSYVIAJ

Mi
,s

Contr. Nat.

Herb.,

Vol. 21.

PLATE II.

SPRING STAGE, AS THE FRONDS ARE UNROLLING.

CINNAMON FERN (OSMUNDA CINNAMOMEA), COMMON IN MARSHES.

PLATE 12.

ON WOODED HILLTOP NEAR

STICHOIDES )

CHRISTMAS FERN (POLYSTICHUM ACRO

DIFFICULT RUN.

PLATE 13.

Contr. Nat. Herb., Vol. 21.

"HONVYRG Nyalsvy YsaMO 7

BHL 4JO LYVd YAddM JHIL NI

HSYVIAJ

SAISNALXO NV

“(SIMLSN Wd WINVZIZ) 3O01W GTI

PLATE 14,

2i.

, Vol.

Herb.

Contr. Nat.

ey
~ ae
oy = ~ =
v4 ae
!
i!
- “ ee
“& by Sibere senna

> ’ 3 At

See

a ie

—

A

vk :

tie

SKUNK CABBAGE (SPATHYEMA FOETIDA) ALONG CABIN JOHN RUN IN APRIL.

Contr. Nat. Herb., Vol, 21. PLATE I|5

B CRESTED IRIS (IRIS CRISTATA) ALONG THE POTOMAC.

Contr. Nat. Herb., Vol. 21.

PLATE 16.

PICKEREL-WEED (PONTEDERIA CORDATA) IN FOREGROUND.

MARSH NEAR DYKE.

Contr. Nat, Herb., Vol, 21 PLATE I7.

A. SPRING BEAUTY (CLAYTONIA VIRGINICA).

B. TROUT LILY (ERYTHRONIUM AMERICANUM .

ld
Contr. Nat. Herb., Vol. 21. PLATE 18.

A. BLUE PHLOX (PHLOX DIVARICATA).

B. WAKE-ROBIN (TRILLIUM SESSILE).

PLaTeE 19.

Vel, 21,

Contr. Nat, Herb.,

“(YOTOOISHSA SIY]) SVIA 3ANI1G ‘GA

‘“(WITOSINISSAS WIYWINAN) LYOM114g ‘V7

PLATE 20

21.

Vo'

Contr Nat. Herb.,

“CATAVOW WNIG3AdIYydAdD)

Y3aMO14 NISVOOOW “Gg

(‘SITI@WLOAdS SIHOYO

SIHOYOQ AMOHS ‘V7

Contr. Nat. Herb., Vol. 21. PLATE 2l.

LIZARD’S-TAIL (SAURURUS CERNUUS) IN A SWAMP NEAR DYKE.

PLATE 22,

Nat. Herb., Vol. 21,

Contr.

AVIA, NI (VWIXVW SNOYH3ND) xvoKaaH “Gg

AVIA NI

(SIMLSNIVd SNOHAND) HAVO Nid ‘VW

PLATE 23.

Contr. Nat. Herb., Vol. 21.

WHITE OAK (QUERCUS ALBA) IN MAY, A LAST YEAR'S GROWTH OF ANDROPOGON

IN FOREGROUND.

ELLIOTTII

PLATE 24.

Contr, Nat. Herb., Vot. 21,

“SHAQ YVAN YSLVAA MOTIVHS NI (VYNGAGYV VAVHdWAN) ATINTONOd MOTIZA

Contr. Nat. Herb., Vol, 21. PLATE 25.

A. HEPATICA (HEPATICA AMERICANA).

'-B. CREAM VIOLET (VIOLA STRIATA).

Contr. Nat. Herb., Vol. 21. PLATE 26.

MAY-APPLE (PODOPHYLLUM PELTATUM) WITH THREE-LEAVED STONEGROP
(SEDUM TERNATUM) BELOW.

PLATE 27,

Contr. Nat. Herb., Vol, 21,

“AATIVA NNY NOXO SHL NI SMOY 39N34 G10 DNOTV SHYNDDO LI SV “(WNITOSIIEWA SVHUAVSSWS) SVWHSVSSVS

=
oe

Contr. Nat. Herb,, Vol. 21

PLATE 28.

A. BLOODROOT (SANGUINARIA CANADENSIS).

B. TWIN-LEAF (JEFFERSONIA DIPHYLLA).

Contr. Nat. Herb., Vol. 21 PLATE 29.

A. DUTCHMAN'S BREECHES (BIKUKULLA CUCULLARIA).

B. SQUIRREL CORN (BIKUKULLA CANADENSIS), LESS COMMON THAN THE
PRECEDING.

PLATE 30.

Vol. 21,

ntr. Nat. Herb,,

“(SISNSINIDYUIA VOVYSIXYS S9VYAIXWS “Gg

“(WLIVINIOV] VINVINAG

1004-Sdd3d ‘Vv

Contr. Nat. Herb., Vol. 21. PLATE 31.

B. STAR CHICKWEED (ALSINE PUBERA).

Contr. Nat. Herb., Vol. 21. PLATE 32,

GOAT'S-RUE ‘CRACCA VIRGINIANA! IN ROCKY WOODS NEAR GREAT FALLS.

Contr. Nat. Herb. Vol. 21. PLATE 33.

BLaAcK LocusT (ROBINIA PSEUDO-ACACIA) IN MAY,

Contr. Nat. Herb., Vol. 21, PLATE 34.

B. PRICKLY PEAR (OPUNTIA VULGARIS) ON PLUMMERS ISLAND.

Contr. Nat, Herb., Vol. 21, PLATE 35.

FLOWERING DOGWOOD (CORNUS FLORIDA).

PLATE 36.

Herb,, Vol, 21,

Contr.“Nat.,

“SNHY34 HOSS ONV ‘NY3Y4 SVWISIYHD ‘YIVHNAGIVIA) HLIM ‘SLISVYd 100 V '(YSONIDNNY1T SALIGOdAH) dV¥SANId

PLATE 37.

Herb., Vol. 21.

Contr. Nat,

‘(SN3d3uY VAVOld4

)

sningayy

ONITIVYL *"G

1004 V

“ALISVUVd
‘CVHYOTSINA WISSTIVHL

SAdld-

1SOH ‘VW

PLATE 38,

7 a tee! OPIS

a adie - 8.4

THICKET OF LAUREL (KALMIA LATIFOLIA), ALONG CABIN JOHN RUN, IN APRIL.

LEAVES EVERGREEN.

PLATE 39.

ert

Contr. Nat, H

‘MNIq YO SLIHM SYHSaMOT14A

“WITo0dILv1 VIN)

qaynv 7

Contr. Nat. Herb., Vol, 21. PLATE 40.

DEERBERRY (POLYCODIUM STAMINEUM). A CHARACTERISTIC SHRUB
STERILE Woops: FLOWERS WHITE.

IN

Contr. Nat. Herb., Vol. 21. PLATE 4l.

B. RoBiNn's PLANTAIN (ERIGERON PULCHELLUS!}

Contr. Nat, Herb., Vol. 21, PLATE 42,

JAPANESE HONEYSUCKLE (LONICERA JAPONICA), AN INTRODUCED VINE NOW
ABUNDANT.