ON TRICHODESMA INDICUM R. Br. and> 
TRICHODESMA AMPLEXICAULE Auctt. 
BY 
L. J. SEDGWICK, f.l.s., i.c.s. 
The question whether there are here two species or not has long been 
u doubtful point. Clarke, who wrote the account of the Boragineoe in the 
Flora of British India, regarded T. amplexicaule Roth as distinct from 
T. indicum R. Br., but discriminated the two species chiefly by the 
leaves. Cooke, in his Flora of the Bombay Presidency gives T. 
amplexicaule as a variety of T. indicum , but again bases the distinction 
Upon the shape and vestiture of the leaves, and remarks of the former 
f ‘ hardy worthy of even varietal rank. I have often tried to find 
even one reliable character by which to distinguish between T \ 
indicum and T. amplexicaule but have failed to do so. The amount of 
hairiness of the lower side of the leaves cannot be relied upon as a 
constant character. I have seen specimens authoritatively recognized 
as T. amplexicaule which were more densely villous than many of the 
other species.” 
A study of these plants during and after the monsoon of 1917 has 
convinced me that there are certainly two very distinct species, differing 
always and essentially in the morphology of the androecium, and the shape 
of the corolla and calyx^ and usually in the characteristics of the leaves 
as well as in habit, habitat and season. I give below in two parallel 
columns the descriptions of the two species, the more important points 
being given in italics. 
T. INDICUM Br. 
Normal Habit 
A low, woody, herb, with a long taproot 
and strong woody stein, 4—10 inches high, 
copiously and diffusely branched from the 
base. 
Normal Leaves 
£ — 1 x £ — £ in., sessile and sub-amplexi- 
caul, margins strongly revolute, villous 
(especially beneath) and with a few rougher 
hairs. 
Pedicels 
Up to 1 inch. 
T. AMPLEXICAULE DC. (not of Roth). 
Synonymy will be discussed below. 
Normal Habit 
An erect herb, 1 — 2 feet high, branched 
(not copiously) above. 
Normal Leaves 
1— 1£ x £—1 in., sessile and sub-amplexi- 
caul, margins not revolutc, scabrid (especi- 
ally beneath) with distant stiff hairs arising 
from prominent bulbous bases. 
Pedicels 
Up to 2 inches. 
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