542 THE FERTILISATION OF FLOWERS. [parr in. 
Orv. SCITAMINE LZ. 
Tribe Zingiberee. 
Hedychium and Alpinia are adapted for cross-fertilisation by 
insects. The visitors must come in contact first with the stigma 
and afterwards with the anthers (172, 352). Delpino conjectured 
that Hedychium must be fertilised by Lepidoptera, and long after- 
wards found scales of ‘Lepidoptera on the stigma of the plant 
(177). Fritz Miller has shown that the flowers of Hedychium 
are arranged so that the pollen may be transported by the wings 
of long-tongued butterflies. . 
Zingiber officinarum.—Cross-fertilisation is ensured in case of 
insect-visits by the prominent position of the stigma (351). 
The cultivated plant in South Brazil is only reproduced by 
vegetative means, and is quite barren, though pollen, stigma, and 
ovule seem to reach normal development. ‘This sterility is 
perhaps due to the plants being all portions of one original 
stock (359). 
Tribe Marantee. 
Calathea (Maranta) zebrina, Meyer, and C. discolor, Lindl., 
have, according to Hildebrand, an explosive arrangement, com- 
parable to that of several Papilionaceze. A hood-shaped petal, on 
the under side of the almost horizontal flower, surrounds the style, 
which carries at its extremity the funnel-shaped stigma, and above 
the stigma the pollen which is shed upon it in the bud. The 
weight of an insect-visitor alighting on the petal itself or on a 
hooked process of it, sets the style free. The style then curves 
backwards and inwards, so that the ventral surface of the insect 
is first swept by the stigma and then dusted with fresh pollen. 
The style in curving backwards closes the path to the honey, 
so that each flower is only visited once (360, p. 617). Delpino 
investigated Maranta bicolor and M. cannefolia, and found their 
flower almost identical in structure with the species described by 
Hildebrand. He, however, found that part of the style between 
the stigma and the pollen secretes a sticky fluid, which is applied 
to the insect’s proboscis and causes the pollen to adhere. 
Thalia dealbata, Fras., has similar flowers, which are visited 
and fertilised abundantly at Florence by the hive-bee. 
Delpino has tried, by comparing the flowers of Marantacew 
with those of Musacew, Zingiberacee, Cannacee, Orchidee and 
Graminew, to trace out the genetic relations of these orders (175). 
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