122 MORPHOLOGY 



passes through the pupa stage, and emerges out of 

 the gall as a perfect insect by biting its way through 

 it. The insect then makes its way through the mouth 

 of the jug to the exterior, and, while creeping otitj its 

 body becomes dusted with the pollen-grains of the 

 male flowers situated near the mouth. It then runs 

 to another inflorescence, enters into it, pollinates the 

 stigmas of the long-styled female flowers, and lays 

 eggs into the short-styled female flowers known as 

 GALL-FLOWERS. The wasps cannot lay their eggs in 

 the cavity of the ovary of the long-styled flowers, as 

 the styles are too long for their ovipositors to reach 

 the cavity of the ovary. Hence no galls are formed 

 in them as in the short-styled flowers, and fertile seeds 

 are produced in abundance. 



In tropical countries like India, birds like crows and 

 mainas, and other animals like squirrels and bats, are 

 useful agents of pollination. These animals are found 

 in numbers visiting the big red open flowers of shimul, 

 the scarlet-red papilionaceous flowers of palthe-madar 

 {Erythrina indica), the showy racemes of large red 

 flowers of Gold Mohur, and the long pendulous spikes 

 of bright-yellow flowers of sondal or Indian Labur- 

 num. These plants blossom at the end of winter, 

 and shed their leaves before flowering, so that the 

 brightly-coloured flowers, freed frorn the interference 

 of a mass of green foliage, become a very conspicuous 

 feature of the scenery, and attract birds, &c., from 

 a distance. 



Well-known water-pollinated plants are compara- 

 tively few, and confined almost wholly to the aquatic 

 ftimily of Hydrocharidacece. A curious example of 

 such plants is common in our tanks, and is known 

 as ganj or pata-shaola (Vallisneria spiralis) (fig. io8). 

 It is a dioecious plant, which lies rooted to the mud 



