SOUTH AMERICAN PLANTS. 75 
their flowers, ought also to form a distinct genus, which no 
one would venture to propose: upon the whole, therefore, 
I would recommend that the genus Habrothamnus be sup- 
pressed, and its species arranged as a particular section 
of Cestrum under that appellation.* 
I may here avail myself of the opportunity of observing 
that the genus Laureria of Schlechtendahl, placed by some 
authors among the Nicotianee is beyond doubt, identical with 
the Juanulloa of Ruiz and Pavon: it ought, therefore to 
be placed among the Solanee, where also Marckea of 
Richard, and Nectouxia of Kunth, should be arranged, as 
they better agree with many of that tribe in habit, and 
as nothing is known of the character of their seeds to warrant 
their being placed among the Reetembryee. 
I have excluded Dunalia from the Cestrinee in the above 
distribution, because nothing is known of the nature of its 
embryo, and for other reasons before pointed out, (ante 
p. 13.) 
In external aspect there is a remarkable resemblance 
between some species of Petunia, Nierembergia and Salpi- 
glossis, so much so, that several able Botanists have referred 
such plants to these three different genera; but there exists 
in the latter, certain decided characters that cannot be con- 
founded with the two former: I do not allude so much to 
the didynamous stamens, with a fifth sterile filament, as 
to the more important one of its deeply reniform seeds, 
and completely annular, and sometimes even spiral embryo, 
while in the two former genera the embryo is nearly straight. 
But there is also another well-marked difference in the esti- 
vation of the corolla, a character of the utmost importance, 
* The, three known species of Habrothamnus thus forming a distinct 
section of Cestrum would be arranged as follows : 
§ HapRoTHAMNUS. 
Habrothamnus fasciculatus, Endl.) | 
—— tomentosus, Bth.) 
__— corymbosus, Endl.) 
L 2 
Cestrum fasciculatum ( 
——— Benthami. ( 
—— Endlicheri. ( 
