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[APRIL 4, 1907 
RIE VLIVING . WiELWITSGHIA: 
N the course of a botanical expedition! in Damara- 
land from Walfish Bay to Windhuk I spent some 
days in January and Vebruary in the littoral desert 
(the Namib), where in several localities Welwitschia 
3. 1.—Welwitschia : “Male Plant. 
is abundant. Speaking generally, the cones seen this 
year on January 22 and on later dates were consider- 
ably more advanced than those examined on January 
13, 1904. The plants are flowering quite as profusely 
as they were three years ago, and, excepting a 
number of immature specimens, few 
were without cones. 
Fig. 1 shows a male plant the leaves 
of which are torn into broad bands. 
Baines might be forgiven for represent- 
ing a plant not very different from this 
by the picture reproduced in Hooker’s 
monograph (Plate i., Fig. 2). The 
tearing of the leaves into narrow strips, 
which on the whole seems to be more 
characteristic, is, I think, less common 
in the eastern part of the Damaraland 
area than in the west. The inflor- 
escences (Fig. 2)—-compound dichasia 
with decussating branches, occasionally 
reduced to solitary sessile cones—are 
inserted in pits on the outer ridge of 
the stem just within the leaf base. 
The ridge in the axil of the leaf re- 
mains fertile for a number of years. 
The lower flowers of most of the cones 
seen in the photograph are open, and 
their anthers are exserted. 
The female plant shown in Fig. 3 
bears an unusually large crop of cones. 
This is also an eastern plant, and the 
leaf-segments are few and broad. The 
bracts are deep, dull red in colour, 
except for a narrow margin of dark 
brown which extends for a short distance only 
on either side of the apex. The general effect is 
to mark out the four angles of the cone by 
longitudinal dark bands, which are separated 
by broader red bands along which the bracts over- 
1 In part assisted by a grant from the British Asso: iation. 
NO. 1953, VOL. 75 | 
f 
| 
lap. In Fitch's picture (Hooker, Plate vii., Fig. 1) 
the angles of the cone are not sufficiently dark, and 
the colour of the remainder is too bright. The lower 
ovules appear to be pollinated. A drop of an intensely 
sweet viscous fluid was found on the summit of the 
projecting micropyle of each of the upper ovules 
during the day. It was not observed 
earlier than 9 a.m., but was common 
at 9.30 a.m. It remained there until 
after 3 p.m., but disappeared before 
sunset. Its formation was not due to 
a general increase in the turgidity of 
the plant, for it appeared before mid- 
day on inflorescences cut off in the 
early morning. Similar drops were 
seen under like conditions on all cones 
of corresponding; size. and colour. ° 
'I -have elsewhere. stated. that -the 
‘ hemipteron Odontopus -sexpunctulatus, 
which in Damaraland is always found 
on the inflorescences during the hotter 
part of the day, is not a pollinating 
agent, and have inferred, contrary to 
the opinion of Schinz, that the relation 
between the insect and the plant is one 
of parasitism only. This statement, 
founded as it was upon too hasty 
observation, is incorrect. Fourteen 
specimens captured in different places, 
some from male and others from female 
plants, and examined microscopically, 
were found in every case to bear pollen. 
The grains adhere singly or in masses 
to the smooth surface of the abdomen, 
or are caught up among the short 
the limbs. I have observed that as 
walks over the cone the abdomen is 
the exserted anthers in the one case 
fluid-tipped micropyle in the other. 
therefore be no doubt that Odontopus is 
hairs on 
the insect 
touched by 
and by. the 
There can 
Fic. 2.—Inflorescences of Welwitschia. 
an important pollen-carrier, though, 1 believe, not 
the only one. The cones are also visited. by a fly 
which is sometimes present in considerable numbers, 
and also by at jeast two species of Hymenoptera. 
In these’ cases the sweet fluid on the top of the 
micropyle is probably a source of attraction, but it 
