1(1 July, 1917.] A iiple Culture in Victoria. 393 



A staminate flower has stamens but no pistil, wliile one of the 

 pistilliferous character has a pistil without stamens. While carrying 

 out observations and collecting data in this regard, the writer was 

 unable to discover an apple tree producing flowers of the former 

 character, while one producing those of the latter was found, photo- 

 graphic illustrations of winch will be given later on. Mr. E. Wallis, 

 Orchard Supervisor, has found in the Bacchus Marsh district an apple 

 tree which was sterile in consequence of its producing staminate 

 flowers. 



Pollination and Fertilization. 



When the sepals and petals, in turn, expand they liberate the male 

 and female organs, which, favorable weather ensuing, soon arrive at 

 the stage of pollination. The pollen, a single grain of which is almost 

 microscopic, but when in clusters may be easily seen by the naked eye, 

 quickly ripens in the anthers, which then burst and liberate it. During 

 this period, in the case of self-pollination, the stigma assumes the 

 condition of receptivity which is indicated by the appearance of a little 

 sticky fluid oozing from it. 



A pollen grain lodges on this fluid in the mouth of the stigma, it 

 then absorbs the moisture, and sends out, or rather elongates into, a 

 tube, which passes down through the centre of the pistil division to 

 the ovary (L), the walls of which are indicated by the arrows. The 

 tube reaches its destination on entering the micropyle, or opening in 

 the ovule, and then acts as a channel through which the protoplasm 

 or living and life-giving fluid is conveyed from the pollen grain to the 

 ovule, which it fertilizes. 



After fertilization has taken place the young fruit commences to 

 swell, and establishes its connexion with the tree through calling on 

 it for support. But blossoms which fail to set fruit, from whatever 

 cause, soon Icse their vitality and part company with the tree at the 

 base of the flower stalk, the point (N). 



Through systematic winter pruning a reasonable quantity of 

 blossom buds of good quality may be maintained on the trees, and 

 usually when from 10 to 20 per cent, of the flowers produce fruit, 

 other conditions being favorable, a good crop may be anticipated. 

 However, trees, which are allowed to exhaust themselves by producing 

 abnormally heavy crops of blossoms through want of scientific prun- 

 ing, may set as many, but inferior fruits, on from 3 to 5 per cent, of 

 their blooms. 



Plate 108 is a diagram showing an enlarged cross section through 

 the ovary of a young fruit. In its normal condition, as shown, the 

 ovary consists of five chambers, the carpels or walls of which are com- 

 posed of a comparatively strong, tough, membraneous substance. But 

 when the pistil divisions deviate from the normal by showing an 

 increase or a decrease in their number, the ovary chambers vary in 

 number correspondingly. Photographic illustrations showing ovaries 

 divided into four and three chambers respectively with corresponding 

 pistil divisions, will be given later. Prior to and during the period 

 of fertilization the ovules stand in pairs in the ends of the chambers 

 next the centre and are so conveniently placed that the pollen tubes 

 are easily brought into contact with them. The relative positions, in 



