350 LECTURE ON SPRING FLOWERING PLANTS. 



There is a curious and interesting fact in the history 

 of plants which the Chinese Primula serves well to 

 illustrate. There is a tendency in most plants to vary 

 in form, size, and colour when transferred from their 

 natural or wild state and subjected to cultivation. The 

 type of the Chinese Primrose of to-day was pink or lilac, 

 and not more than one-fourth of the present size. By 

 culture, through the means of a rich soil and careful 

 attendance, the size has increased, and by watching for 

 even slight variations in form and colour, and selecting 

 such as the parents of future races, the change went 

 gradually on. A break, as it is termed, was at length 

 obtained that is, a departure from the normal form. A 

 standard of excellence was set up, but it was found that 

 such, although occasionally realised, could not be retained. 

 It was found that seeds saved from the Red Primula would 

 sometimes produce both red and white flowered plants, 

 and seeds saved from White Primulas would do the same, 

 while the seedlings varied greatly in size, colour, and form. 

 The break was retained, but the result was uncertain. 

 The next step was to fix the alteration. Year after year 

 plants of the altered and more approved form, closely 

 resembling each other, were selected and placed apart, 

 and from these alone seeds were saved until the altered 

 form was fixed again that is, seed saved from Red 

 Primulas produced, with almost unerring certainty, red- 

 flowered varieties ; seed saved from White Primulas white- 

 flowered varieties, both preserving the increased size, 

 altered forms, and clear decided colours of their immediate 

 progenitors. 



Take another instance. There are before you plants of 

 the new Double Crimson Thorn. Strange as it may seem, 

 this is descended from the common Whitethorn or May 

 of our hedges. But this has not happened suddenly, but 

 by a gradation of changes. Most observers will doubtless 

 have noticed in our hedges that some of the plants produce 

 flowers of a pink tinge, though still with single flowers. 



