14 ON SOUTH-AMERICAN APOCYNACEAE. 
to the dissepiment ; the albumen is 22 lines long, 3 line thick; radicle superior, 3 times 
as long as the short obtuse linear cotyledons. 
` A figure of the inflorescence of this species, and of its fruit and seeds, are exhibited in 
Plate 1 B. 
The Zabernemontana lucida, H. B. K. (Gen. vii. 209), appears to belong to Lacmellia, 
as shown below. 
To be excluded :— 
Ambellania quadrangularis, Müll. = Rhigospira quadrangularis, nob. 
Ambellania macrophylla, Müll. = Rhigospira venulosa, nod. 
LACMELLIA. 
This genus was established in 1856, by Karsten, upon a New-Granada plant, naming 
it after its vernacular title, ** Leche e miel" (milk and honey). It has been acknowledged 
by Messrs. Bentham and Hooker (Gen. ii. 694), but only by absorbing into it Múller's 
genus Zschokkea : the latter appears to me, however, a valid genus, as will presently be 
shown. Only one species has been hitherto known; but a second and closely allied 
species is here added, from one of Bonpland’s plants. 
1. LacmeLLIA EDULIS, Karst. Linn. xxviii. 450. Rio Meta, in littoribus (non vidi). 
A middle-sized tree, growing on the banks of the river Meta (flowing from the New- 
Granada Andes), at a spot about 70° 40' W. long. and 60° 20' N. lat. : its trunk yields a lac- 
tescent juice, made into a cooling drink; it is crowned by a branching head ; its opposite 
leaves are shining above, and on short petioles. The inflorescence is an axillary cyme of 
small yellow flowers, on bibracteolated pedicels; the calyx consists of 5 small, concave, _ 
imbricated, persistent sepals; the corolla is tubular, with a border of 5 linear lanceolate 
segments, twisted in sestivation and deciduous; the stamens, on very short filaments, 
are inserted in a pilose ring above the base of the tube of the corolla; the ovary is single, - 
bilocular, with many hemianatropous ovules in longitudinal series in the axis; the style 
is conical, 10-costate; stigmata 2, lanceolate. The fruit is yellow, oval, baccate, as large 
as a hazel nut, crowned by the persistent style; by abortion it is 1-celled and contains a ` 
single, good-tasted seed enveloped in a mucilaginous covering; the albumen, as long as - 
it, encloses the heterotropous embryo, of 2 oval foliaceous cotyledons conjoined by a 
superior fusiform radicle. 
2. LACMELLIA LUCIDA, nob.: Tabernemontana? lucida, H. B. K. vii. 209; Psychotria lucida, R. € Sch. í 
(non H. B. K.), Syst. iv. 189. In Nova Granada ad Rio Atabapo (non vidi). 
A closely allied species, collected by Bonpland at the Missiones of S. Francisco, in the ` 
same longitude, and about 50 miles southward of the locality of the preceding species. 
It forms a lactescent tree 50 feet high, growing on the border of the river, with fuscous ` 
branches 2-edged, compressed, smooth and incrassate, the axils by a transverse ridge : 
conjoining the petioles; leaves opposite, oblong lanceolate, obtuse or rounded, rarely ` 
emarginated at the apex, narrowly cuneated at the base and running into the petioles, : 
subcoriaceous, glabrous, thickened and entire on the margins, with many approximated | 
parallel faint nerves, nitid above, concolorous beneath, with a prominent midrib, 3-3} in. ' 
