On the Heteranthus Section of Cuphea 
(Lythraceae). 
BY 
T. A. SPRAGUE, B.Sc. (Edin.) 
Assistant in the Herbarium , Royal Gardens , Kew. 
With Plate XI. 
History and Taxonomy. 
HE section Heteranthus was established in 1877 by 
-1 Koehne ( 3 ), who created it to receive his three new 
species, Ctiphea setosa , C. epilobiifolia, and C. tetrapetala , 
which had this character in common that in each pair of 
opposite flowers one flower was older. He also placed 
C. rigidula , Benth., doubtfully in the section. In 1881 ( 5 ), 
while giving more detailed descriptions of his three species, 
he placed C. rigidula next to C. setosa , omitting all mention 
of the repeated dichasial branching of C. rigidula , which he 
evidently did not credit. In succeeding years Koehne added 
four other species, all from Colombia, one of which, C. Leh - 
manni , does not possess the character from which the section 
takes its name, namely the unequal age of the flowers of each 
pair. The two new species described in the present paper 
also alter the character of the section in important details, 
namely the presence of two petals only, and the occurrence 
of an erect instead of a deflexed disc. It may, therefore, be 
[Annals of Botany, Vol. XVII. No. LXV. January, 1903.] 
