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HUTCHINSON'S POPULAR BOTANY 



are adapted for fertilization exclusively by long-tongued crepuscular and 

 nocturnal moths : and why ? Because the wax-like tubes are long and 

 narrow too long for short-tongued insects to reach the honey while 

 standing at the mouth of the flower, and too narrow to enable them to 

 descend bodily to the nectary. As a matter of fact, the flowers bloom at 

 the very season when hawk-moths are most abundant that is, during May 

 and June and they exhale their perfume most strongly in the evening, 

 when these moths are on the wing. 



Another form of gamopetalous corolla which must not be passed over 

 is that which, from its resemblance to a funnel, has received the name 

 infundibuliform. The name is less elegant than the flower to which it 

 is applied. The delicate white chalices of our beautiful Hedge Convolvulus 

 (G. aepium) are of this form. Funnel-shaped flowers have not such a 



reputation for exclusiveness as have those 

 of tubular and salver shape ; and it has been 

 observed of the Hedge Convolvulus that 

 all sorts of thrips and little flies frequent 

 the flowers by day, sheltering and feeding 

 there, though they confer no benefit in 

 return. Only on bright, moonlight nights, 

 when the sphinx-moths are about, does the 

 plant reap any advantage from its visitors. 

 A friend of the naturalist Delpino, standing 

 by a hedge overgrown with this Bindweed, 

 was able to capture numbers of one species 

 of sphinx-moth (S. convolvuli] simply by 

 closing with finger and thumb the orifices 

 of the flowers as the moths inserted -their 

 heads. 



A form of corolla closely related to the 



infundibuliform is the campanulate, or bell-shaped. We have examples 

 of a regular campanulate flower in the Rampion (Campanula rapunculus, 

 fig. 426) and other Bell-flowers, and of an irregular or oblique campanulate 

 flower in the equally well-known Foxglove (Digitalis, fig. 420 j. The wide 

 bell-shaped corollas of Campanula are specially adapted for humble-bees ; 

 but the flowers number other kinds of bees among their visitors, and 

 numberless beetles and small flies use them as shelters from the rain or 

 make the comfortable bells their night quarters. The Foxglove is also 

 specially adapted for humble-bees, for, says Hermann Miiller, " no other 

 insects are large enough to touch the stigma and anthers with their backs 

 when creeping into the tube." They are, in fact, the only pollinators of 

 the Foxglove. Possibly the enlargement of the under side of the corolla, 

 which gives the irregularity to the flower, is intended as a landing-stage 

 for the insect (it is certainly so used), and may also be an arrangement 



FIG. 419. ROSACEOUS COROLLA 

 OF A BUTTERCUP. 



