POLLEN AND POLLINATION 



4743 



POLL TAX 



the plant itself, and cross-pollinated flowers 

 are those which must depend upon other agents 

 to carry the pollen of one flower to the stigma 

 of another. Usually inconspicuous and odorless 

 flowers and those whose stigmas, before wither- 

 ing, curve so as to come into contact with the 

 anthers, are self-pollinated. 



Insects as Pollen Carriers. When flowers are 

 not capable of self-pollination they are equipped 

 with various aids to assist in cross-pollination. 

 In some, the showy blossom, in others, the fra- 

 grant scent, in still others the sweet nectar, at- 

 tracts insects to the flower. 



The most important carriers of pollen are 

 the honey-bees, which flit from flower to flower 

 to sip the nectar, which they convert into honey. 

 As they wallow in the pollen they rub the 

 grains on their hairy bodies. They are pro- 

 vided with twc tiny cups on the hind legs for 

 the carrying of pollen to their nests, but that 

 which is scattered over their bodies is shaken 

 off on the flowers they afterwards visit. Usu- 

 ally the flowers whose color attracts bees are 

 red, blue or pink ; in yellow and white blossoms 

 it is the nectar that attracts the insects. The 

 importance of these insects to plant life is 

 shown by the fact that when some vegetables 

 are grown under glass, it is necessary to keep 

 a swarm of bees in the hothouse to insure pol- 

 lination of the flowers and consequently an- 

 other crop. 



Ants, beetles, moths and butterflies are other 



pollen carriers. Some flowers are adapted to 



pollination by certain insects. Those which 



off their fragrance at night, such as some 



of honeysuckles and petunias, are pol- 



* 







a 



o 



I'ES OF POLLEN GRAINS 

 Dandelion; (b) hemp; (c) gentian 

 quash. 



(d) 



linatcd by night moths, and those which are 



most fragrant in the sunlight attract day-flying 



bees and butterflies. Other flowers, such as the 



which the nectar is deeply hidden in 



corolla, cannot be pollinated by small in- 

 sect*, although the pollen grains can easily be 



. ! I'.v th< tongues of bees. In the snap- 

 dragon, the little trapdoor concealing the pol- 

 len can be pushed open only by large insects. 



nteresting example of the dependence of 

 a flower upon one particular kind of insect is 

 een in the fig, which cannot produce seed 



will grow unless pollinated by a small wasp. 

 The bloom of the yucca tree is self-pollinated 

 only by the yucca moth, which lives in the 

 flower. 



Wind and Other Agents. The wind scatters 

 the light, dry pollen of many flowers an.i 

 and the humming bird carries that of the wild 

 balsam, trumpet creeper, gladiolas and similar 

 flowers. Many of Luther Burbank's efforts in 

 producing new varieties of plants are the result 

 of artificial cross-pollination. E.B.P. 



Related Subject*. The reader is referred to 

 the following: articles in these volumes: 



Bee, subtitle The 



Honeybee 

 Burbank, Luther 

 Cross-Fertilization 



Flowers, subhead 

 Flower Structure 



Germination 



Seeds, subtitle Seed 

 Dispersal 



POLL, pohl, TAX. The term is derived 

 from the English poll, which means head; it is 

 sometimes called capitation tax, from a Latin 

 word meaning head. A poll tax is therefore a 

 uniform tax levied upon individuals without 

 reference to their property, business or employ- 

 ment. There have been instances where a poll 

 tax has been levied upon persons in which the 

 amount assessed depended upon the wealth of 

 the individual, but in the United States espe- 

 cially such a tax is illegal, the Constitution de- 

 claring that all such direct taxes levied by Con- 

 gress must be on the basis of population, mean- 

 ing on each person, and not based upon wealth. 

 The first income tax bill of the United States 

 was essentially a poll tax, but was declared un- 

 constitutional because there was not a uniform 

 levy against all people. 



The United States Congress has ne\< : 

 cised its right to levy a poll tax, but many 

 states of the American Union provide this as 

 one of the means of raising revenue, and in 

 some of them the n^ht to vote depends on tin 

 payment of a poll tax. On the other hand, it 

 is within the province of a state to declare 

 against the poll tax, and a few have done so on 

 the ground that it is harsh and oppressive. It 

 is certainly an unpopular tax, since the people 

 naturally tV< 1 that government revenue should 

 be levied on property, v poll taxes are 



levied the money (icn\.d ii placed with tin- 

 general revenues of the taxing body, and is not 

 set aside for special purposes. 



In Encli-h history a poll tax has been im- 

 posed on occasions, the lost being in 

 1698. Three hun.h tier a lev] 

 tin- nature wa- the occasion of the brief rebel- 

 lion of Wat Tyler. 



