572 TRANSACTIONS OF SECTION K. 
of the same sort was felt by Shakespeare three centuries ago, and it remains the 
same to-day. Nay more :—it may lead us even to forecast future possibilities. 
In following our evolutionary quest in this spirit we shall find that we are 
indeed— 
‘Figuring the nature of the times deceased, 
The which observed, a man may prophesy 
With a near aim, of the main chance of things 
As yet not come to life.’ 
(King Henry IV., Part II., Act iii., Scene i.) 
MELBOURNE. 
VRIDAY, AUGUST 14, 
The following Papers were read :— 
Wve Double Stock—Ils History and Behaviour. 
By Miss E. R. Saunpers. 
* There is some evidence that the cultivation of the garden Stock dates back 
to Greek and Roman times, the double-flowered plant being then unknown and 
presumably not in existence. 
There appears to be no definite record of the time or place of first appearance 
of the double form, but for various reasons we may conclude that it made its 
appearance only shortly before the date when it is first mentioned (middle of 
sixteenth century). A comparison of the frequency of reference to the double form 
of the three genera included at this time under the same name (Leucoium or 
Viola), viz., the Violet, the Wallflower, and the Stock, seems to show that they 
arose successively in the order named. 
The original method of propagation of the double Stock (which is sterile) 
was by slips or cuttings, the double having appeared first in the biennial types. 
The fact that the double was obtainable from the seed of singles was not 
generally known for more than a century after the plant was in cultivation. 
Many different methods of procedure and treatment have been advocated from 
time to time as leading to the production or increase of double-flowered plants, 
but none have stood the test of experiment. 
Mendelian methods of analysis have enabled us to arrive at an understanding 
of the relation of the double to the single, and have shown that the output 
of doubles is constant and independent of external conditions. By appropriate 
selection, in some cases of seeds, in others of the young plants, it is sometimes 
possible to obtain, not an increased output of doubles by the individual, but an 
increased proportion of double plants in the flower-beds. 
2. On the Sex Dimorphism and Secondary Sea Characters in some 
Abnormal Begonia Flowers, and on the Evolution of the Monecious 
Condition in Plants. By C. I. Bonn. 
In certain Begonias the presence of an abnormal floral bract frequently indi- 
cates an associated abnormality of the sex organs in the flower which terminates 
the pedicle on which the abnormal floral bract appears. This abnormality may 
take various forms, from simple multiplication or modification of accessory floral 
parts to complete hermaphroditism. The relative position of the male and 
female sex organs on the floral axis indicates whether the flower is primarily 
male or primarily female. 
The Terminal Position of the Male Flower in the Normal Begonia Inflorescence. 
The diccious, the monecious, and the hermaphrodite forms of sex dimorphism 
are the result of a process of qualitative cell division among different cell units, 
at different stages of their development. This sex differentiating cell division 
