Asclepias angustifolia Sessé & Moc.

6. Asclepias linifolia H.B.K. Nov. Gen. et Sp. 3: 190. 1818.
Asclepias salicifolia Lodd. Bot. Cab. pi. 2J2. 1823. ,
Asclepias Arizonica Greene. Name only in Herb. Gray.
A low shrub, glabrous except for a minute pubescence on stems
and pedicels. Stems erect, 4—6 dm. or 1 m. high, solitary or several
together or 1—2 or more at intervals from a stout rootstock, com-
monly branched, minutely pubescent, mostly in lines above : leaves
opposite, tapering to a slender petiole; blades narrowly linear, 7—14
cm. long, 2—3 or 4. cm. wide, acute at each end, glabrous ; mar-
gins often revolute ; midvein whitish, the widest leaves with ob-
scure but ascending veins : umbels lateral, several, on peduncles
longer than the 1 cm. long pedicels,, several to many-flowered :
corolla-segments greenish-white, 3.5-4.5 mm. long, acutish : hoods
erect, white, one-third higher than the anthers, rounded at the
summit, dorsally hastate-sagittate at the base; ventral margins
slightly involute, entire; horn flat, falcate, adnate to the keel of
the hood from the base un to about the middle* lonf-exserted
over the anthers : anther-wings slender, angled and salient at the
base, apparently entire : follicles very slender, 4—4.5 cm. long,	„
glabrous, tapering at each end: seeds 4 mm. long, very thin :
coma 1.5 cm. long.
A species easy to distinguish from its allies by the hoods, which
exceed the anthers, a character which never occurs in any of the
species enumerated above as being related to A. verlicillata.
Arizona: Santa Catalina Mts., Lemmon, 1881, and “by streams	—.
of Santa Catalina Mts.,” Pringle, 1881 ; Huachuca Mts., Lemmon,
1882; Fort Huachuca, T. E. Wilcox, 1892. Mexico: San Luis	I	'
Potosi, Schaffner, no. 58, in Herb. Canby; State of Nuevo Leon,
Pringle, no. 1895 in Herb. Columbia University.
A small specimen said to have grown “ in Mr. Hogg’s garden
1825, raised from seeds collected by Dr. James in Long’s Expedi-
tion to the Rocky Mountains ” is preserved in Herb. Torrey. It
appears to belong here, but the flowers are in too poor a condi-
tion to make it certain. The sheet on which it is pasted bears a
note by Dr. Gray to the effect that “it most likely equals A. vir-
gata Lagasca, but has the horivtoo long.”
A specimen from San Luis Potosi, collected by Parry and
Palmer, no. 581, might also be referred to, this species and in
fact it is partly so labelled, but it is much more, branching in habit
and has somewhat shorter leaves.
Asclepias linifolia is referred to Asclepias angu^tifolia Schweiger,
Enum. Hort. Bot. Regiomont, 13. 1812 by Hemsley,.but Four-
nier (Ann. Sci. Nat. VI. 14: 376. 1882) notes that it would
be difficult to determine whether it belongs to A. linifolia or to A.
virgata Lag. (1804). I have seen no authentic specin
except for the somewhat broader leaves, and is the s;
probably the origin of many garden specimens.
Should all of these names fail to belong here I have added
to them the name which appears on a plant collected by Lem-
mon in Herb. Gray, Prof. Greene having long ago recognized it
as a good species.
latter species. It is said to have “ Corollae albae, co;
livido suffusae.”
The plant in Loddiges’ Catalogue was made from
raised from seed, habitat unknown, but it seems to be
Herbarium of Columbia University, New York.
Asclepias effaces
|sjr-\A/ vnnk rdtanicalgarden Det. R. E. Woodson, Jr.
1952
04175669
m
04175669