Orthosiphon. | LABIAT (Brown). 253 
KataHari Region : Transvaal; Mac Mac, Mudd ! 
This species only differs from O. albijlorus, N. E. Br., in its more conspicuously 
bracteate inflorescence and larger flowers. It may possibly be a sexual state of 
that species, but this can only be determined from observation of the living 
plants. 
18. 0. subvelutinus (Guerke in Engl. Jahrb. xxvi. 80) ; stems 
several from a woody rootstock, 7-27 in. high, $-1} lin. thick, 
minutely tomentose with branched hairs ; internodes 3-5 lin. long ; 
leaves with very short densely leafy branchlets in their axils, sub- 
sessile, ascending or spreading, 2-5 lin. long, }-2} lin. broad, rather 
thick, linear or some of the primary ovate, acute, very revolute at 
the margins, minutely tomentose with branched hairs on both sides ; 
flower-whorls }—} in. apart, 2-6-flowered, in racemes 14-3} in. long ; 
bracts 14-3 lin. long, 1-1} lin. broad, ovate, acute, tomentose like 
the leaves, persistent ; pedicels 3-1 lin. long ; calyx-tube 2}-2} (in 
fruit 3) lin. long, campanulate, at first more or less tomentose out- 
side with very minute branched hairs, mixed with long simple and 
gland-tipped hairs, minutely puberulous within ; upper tooth 
1-13 lin. long, 14-1} lin. broad, very broadly ovate, obtuse ; lateral 
and lower teeth somewhat variable, bristle-like from a deltoid base 
or narrowly deltoid-attenuate, the lower }-1} lin. long, all ciliate ; 
corolla much exserted, more or less tomentose (or sometimes nearly 
glabrous on the tube) outside with minute branched white hairs ; 
tube 44-6 lin. long, rather variable in outline curvature, slightly 
enlarged and compressed at the upper part and 1}—13 lin. broad 
vertically ; upper lip or truncate mouth of the tube 13-2 lin. long, 
its broadly rounded lateral lobes much shorter than the small 
rounded or subquadrate obtusely bifid terminal lobe ; lower lip 
1-12 lin. long, elliptic or suborbicular, obtuse or subacute, very 
concave; stamens all exserted or the upper pair included and 
inserted 14-2 lin. above the base of the corolla-tube, 3-5 lin. long, 
with free flat filaments, ciliate along one margin on the basal part ; 
lower pair 1-12 lin. long, free to the base or their filaments united 
for 1} of their length, glabrous ; stigma very slightly thickened, 
very shortly bifid; nutlets } in. long, ellipsoid-oblong, dark brown, 
shining. 0. heterophyllus, Guerke in Engl. Jahrb. xxvi. 82. 
Katanart Recion: Transvaal, Lydenburg district ; near Lydenburg, Ather- 
stone! Burtt Davy, 1643! near Paarde Plaats, Wilms, 1152! near Spitz Kop, 
Wilms, 1155! and 1148 ex Guerke, Mac Mac Falls, Burtt Davy, 2536 ! 
In the authentic specimen of 0. heterophyllus (Wilms 1155) at Kew the filaments 
of the lower pair of stamens are free to the base, whilst in the corresponding 
specimen at the British Museum they are united. This character taken alone 
would, upon the acceptance of Briquet’s genus Hemizygia, place the different 
specimens of this plant under two genera, for I can find no other distinction 
between these two specimens, nor between them and O. subvelutinus (Wilms 
1152), in which the filaments of the lower pair of stamens are also united in the 
specimen at Kew. I believe the union or non-union of the filaments in this plant 
to be either some sexual condition or to have some connection with different 
modes of fertilisation. The flowers on different specimens and sometimes even 
on the same specimen are distinctly variable, so that it may be of hybrid origin. 
