BIRD-POLLINATED PLANTS 



73 



Garden, makes a communication regarding the pollination by bats of an indigenous 

 species, Bauhinia megalandra (sp. nov.). The tree has a height of about lo metres. 

 Its long white flowers bloom in the evening hours, from about four to six o'clock. 

 (Darkness sets in about six o'clock at the season when this plant is in flower 

 (January) in Trinidad.) About half an hour previously bats of various species 

 may be observed flying with great rapidity from flower to flower, and it can- be 

 observed that their visits are immediately followed by the fall of the white petals 

 to the ground. If the tree is examined next morning, not a single complete flower 

 will be found, all of them being more or less torn, and robbed of their long white 

 petals and stamens. When a bat settles on a flower, it holds fast by the projecting 

 stamens, apparently seizing the erect recurved petals, for these are completely 

 scratched or broken to pieces, or else torn off". The stamens are often broken 

 off" short at their bases, but the stigma seems to be seldom injured. 



There does not appear to be any secretion of nectar, and it is therefore probable 

 that the bats visit the flowers for the sake of such insects as are attracted by the 

 odour of the flowers. In order to capture these insects, the bats occupy such 

 a position in the flowers that they effect pollination. 



Mr. J. H. Hart supplements these observations in a letter to me, pointing out 

 that the flowers of yet another tree, Eperua falcata (' Wallaba ') are visited by bats. 

 Glossonycteris Geoff"royi Gray, a species in which the brush-like tongue resembles 

 that of a humming-bird, was captured on the flowers of Eperua in the Botanic 

 Gardens at Trinidad. Its behaviour when visiting the flowers is so hke that of 

 moths, that at first it was taken for one of them. There can be no doubt that 

 it pollinates the flowers of this tree (cf. P. Knuth, 'Neue Beobachtungen uber 

 fledermausbliitige Pflanzen,' Bot. Centralbl., Cassel, Ixxii, 1897). 



{b) Plants with Bird-pollinated Flowers, Ornithophilae (O) '. 



Plants in which the flowers are pollinated by birds (humming-birds, honey- 

 suckers, rarely sparrows) are found in the tropics. 



The first observations on the regular visits of birds to flowers in tropical 

 America belong to the first half of the eighteenth century. The descriptions 

 and illustrations ascribed by Kronfeld (Bot. Centralbl., 1, 1892, pp. 290-4) to the 

 gardener Franz Boos, are taken, according to Loesener (Bot. Centralbl., H, 1892, 

 pp. 138, 139), from a work by Catesby ('Natural History of Carolina, Florida, and 

 the Bahama Islands,' 1731). 



About a century and a half elapsed before another and larger work gave 

 a thorough account of the visits of humming-birds to flowers. In his celebrated 

 book, 'The Naturalist in Nicaragua' (London, 1874), Thomas Belt cites the 

 pollination of Marcgravia nepenthoides by humming-birds as a notable example. 

 This is a climbing plant that ascends to a great height, and possesses pendulous, 

 long-stalked flowers arranged in a circle. A prolongation of the axis of the 



' After the completion of this part of the manuscript I received a work by my botanical friend 

 Professor E. Loew, 'Uber oinithophile Pflanzen' (from 'Festschrift zum i5ojahrigen Bestehen des 

 Konigl. Realgymnasiums zu Berlin,' 1897). In this work the material involved is treated in an 

 exhaustive manner. 



