BIOLOGY AND LIFE HISTOEY. 11 



or beaten down by rains upon the branches, where under favorable 

 conditions the seeds germinate, and if the seedling becomes estab- 

 lished upon the branch it grows again to the age of producing flowers 

 and seed, and so on from generation to generation. Of course the 

 mistletoe seed is more limited than the hackberry in its choice of a 

 substratum upon which to grow, since the only situation in which it 

 has any prospect of developing a plant is upon some part of a living 

 tree. 



DEVELOPMENT OF FLOWERS AXD FRUIT. 



The flowers of the American mistletoe are minute and incon- 

 spicuous, although in some tropical mistletoes they are relatively 

 large and showy. The flowering season in Texas falls usually in 

 December, which is approximately the date of flowering for the 

 species throughout its range. The plant is dioecious; that is, any 

 one individual is wholly male or wholly female. Manifestly some 

 plants never produce berries. This separateness of pollen-produc- 

 ing and ovule-producing plants makes it a matter of importance 

 whether female and male plants grow in close proximity and whether 

 there are any special means by which pollination is effected. Sev- 

 eral of the conspicuous-flowered tropical mistletoes are regularly 

 pollinated by insects. It is claimed also that the European mistletoe 

 (Viscum album) is pollinated by insects, but so far as has been deter- 

 mined the American mistletoe apparently depends upon the wind to 

 carry its pollen. 



After the flowering period and pollination, the development of 

 seed and berry goes forward very slowly. With the approach of the 

 following winter the berry begins' to enlarge and by December the 

 seeds are ripe and the berries pulpy and white. Thus it happens that 

 the flowering season of this }^ear coincides with the ripening of fruits 

 begun a year ago. 



DISTRIBUTION OF SEED BY BIRDS AXD OTHERWISE. 



The seed when ripe is inclosed in a clear, sticky pulp covered by a 

 tough, semitransparent skin, the whole constituting the mistletoe 

 berry. This pulp appears to be in some degree an object of food 

 to certain birds, notably to mocking birds, cedar birds or waxwijogs, 

 and to robins in Texas, 6 and the seeds are distributed in considerable 



a In the case of the European mistletoe the sticky pulp of the berry is utilized in the 

 preparation of bird lime. 



& Doubtless most berry-eating birds feed more or less upon mistletoe berries, 

 according to the abundance or scarcity of other, choicer kinds. Thus in Bulletin 

 Xo. 120 of the University of Texas on the American mistletoe, page 7, Mr. York 

 reports that sparrows and cardinals are the principal birds, next to the mocking 

 birds, which feed upon mistletoe berries. 

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