34 SILVA OF NORTH AMERICA. RHAMNACES. 
appearing in exposed situations on sunny hillsides or in the neighborhood of the ocean. It is tree-like 
in habit and size only in a few favored localities in some of the interior valleys of central California, 
and on Cedros Island and the Santa Barbara group, where, as also on the mountains of the adjacent 
mainland, an arborescent form! occurs having prominently toothed leaves, rather larger flowers with a 
shorter calyx-tube, shorter and broader calyx-lobes, a less deeply divided style, and larger fruit. 
Rhamnus crocea was discovered in 1836 near Monterey by Thomas Nuttall.’ It was introduced 
into England by Theodore Hartweg* in 1846, but probably was soon lost from gardens. It is well 
worth cultivating in all temperate regions for its bright evergreen foliage and brilliant red fruit. 
1 Rhamnus crocea, var. insularis, Sargent, Garden and Forest, u. 
364. 
R. insularis, Greene, Bull. Cal. Acad. ii. 392 ; Pittonia, i. 201. 
R. crocea, Lyon, Bot. Gazette, xi. 333.— Brandegee, Proc. Cal. 
Acad. ser. 2, i. 225. — Vasey & Rose, Contrib. U. S. Nat. Herb. i. 14. 
This is a tree often growing to the height of twenty-five or thirty 
feet, and flowering six weeks later than the ordinary form of R. 
crocea. Flowers provided with petals are said to occur (Trelease, 
Trans. St. Louis Acad. v. 365), but I have not seen them. 
2 Thomas Nuttall (1786-1859) ; a native of Settle in the West 
Riding of Yorkshire, and from 1807 to 1842 a resident of the 
United States, where he made many long and arduous journeys in 
the prosecution of his studies in natural history. Nuttall was an 
accomplished and distinguished naturalist, and one of the most 
indefatigable and judicious of the botanists who have studied the 
North American flora. Among his numerous publications are some 
of the most valuable contributions that have been made in the field 
of North American botany; and his work on North American 
In 1834 Nuttall was 
appointed curator of the Botanic Garden of Harvard College, and 
birds is still an authority on the subject. 
instructor in botany. The duties of the office were not congenial 
to him, as they interfered with his love for travel and prevented 
him from carrying on his investigations in the field, and he ap- 
pears to have passed only a small part of his time in Cambridge. 
He resigned his position in 1842 and returned to England to take 
possession of a handsome estate bequeathed to him by an uncle, 
and to indulge his taste for horticulture. Nuttallia, a handsome 
shrub of Oregon and California belonging to the Rose family, fixes 
the name of Nuttall in the annals of botany, and serves to com- 
memorate his early explorations and his hardships and dangers on 
the plains and in the forests of the far West. 
8 Karl Theodore Hartweg (1812-1871) was a native of Carls- 
ruhe, and the descendant of a long race of famous gardeners. At 
an early age he found employment in the Jardin des Plantes in 
Paris, and afterwards in London in the garden of the Royal Hor- 
ticultural Society, where his industry and intelligence soon attracted 
attention and led to his being sent to Mexico by the society to col- 
In 1836 Hartweg left England on this mis- 
sion, passing seven years in Mexico, central and western equatorial 
lect plants and seeds. 
America, and in Jamaica, making important discoveries, including 
many coniferous trees of the Mexican highlands, and several or- 
chids which he successfully introduced into cultivation. Hartweg 
returned to Mexico in 1845, and was in California in 1846 and 1847, 
spending much of his time at Monterey and penetrating to the 
upper valley of the Sacramento River. On his return to Europe 
he was appointed by his friend, the Grand Duke of Baden, inspector 
of the ducal gardens at Schwetzingen, a position which he con- 
tinued to fill during the remainder of his life. His American 
plants were described by Bentham in the Plante Hartwegiane. 
Hartwegia, an epiphytal orchid, which he first found growing on 
the eastern declivities of Mount Orizaba, was named by Lindley in 
honor of its discoverer. 
EXPLANATION OF THE PLATES. 
Puate LIX. RaAMNUS CROCEA. 
. A flowering branch of the staminate plant, natural size. 
. A flowering branch of the pistillate plant, natural size. 
A staminate flower, enlarged. 
. Vertical section of a staminate flower, enlarged. 
. A pistillate flower, enlarged. 
. Vertical section of a pistillate flower, enlarged. 
A fruiting branch, natural size. 
- Cross section of a fruit, enlarged. 
WWMWNA TR WN 
A seed divided transversely, enlarged. 
bah 
S 
- An embryo, much magnified. 
—_ 
poob 
. Nutlet showing the dehiscence, enlarged. 
PiateE LX. RHAMNUS CROCEA, var. INSULARIS. 
. A flowering branch of the staminate plant, natural size. 
A flowering branch of the pistillate plant, natural size. 
A staminate flower, enlarged. 
. Vertical section of a staminate flower, enlarged. 
. A pistillate flower, enlarged. 
. Vertical section of a pistillate flower, enlarged. 
. A fruiting branch, natural size. 
. Cross section of a fruit, enlarged. 
CONRoT PWD 
. Vertical section of a fruit, enlarged. 
— 
=) 
. A seed divided transversely, enlarged. 
= 
—_ 
. An embryo, much magnified. 
