THE AUSTRALIAN NATURALIST, 79 
visited by myriads of a small weevil (Hlleschodes eupo- 
matie). They alight on the fertile stamens, climb up to 
the top of the flower, and bore their way in to the disc, 
where they feed on a secretion produced by the disc. 
They drop off with the falling flower, and, dusted with 
pollen, fly to another flower, which they cross-pollinate 
while feeding. A few flowers are likely to be self-pol- 
linated in the first visit or two, but afterwards cross-pol- ~ 
lination is the rule. 
In the related families Composite, Campanulacer, 
Goodeniacer, and Candolleacex, there is a similarity of 
mechanism, which, however, works very differently in each 
family. 
In the Composite, the stamens are united in a tube 
round the style, the stigma is closed, and the upward 
growth of style and stigma pushes the pollen out. The 
outer disc florets open. first, and as the visitors alight, 
they are smeared with pollen. The stigmas of the outer 
row then open, and are receptive, while the next inner » 
row comes into the pollen-bearing stage. Insects coming 
from one flower-head, with a load of pollen, deposit it — 
on the stigmas of the outer row of the next head they 
visit, and working inwards, take up more pollen, which 
again pollinates the outer rows in the next visited, and — 
so on. 
In the Campanulacew the stamens are also in a ring ~ 
round the style. But the Campanulas and Wahlenbergias 
differ from the Lobelias in the method of pollination. In 
Lobelia the anthers open, and the growth of the style, 
erowned by the closed stigma covered with a brush of 
hairs, sweeps the pollen out. The flower is horizontal, 
and insects alighting on the lip and inserting their heads 
in the tube, receive a’ load of pollen. When the brush- 
like head emerges from the tube, the hairs dry up and 
drop off, and the stigma opens, exposing its receptive 
surface. - Visiting insects then deposit pollen on it, and- 
pollination is complete. 
In Wahlenbergia and Campanula the ring of stamens 
is below the closed stigma. When they dehisce, closely 
pressed to the style, the pollen adheres to sticky glands ~ 
on the style. At this stage the flower opens, and the 
stamens dry up and drop out, leaving the style coated — 
with pollen. Bees visit the flower, and forcing their way 
