Presumptive Mutations in Wild & Cultivated Plants 69 



in a single character, having yellow or orange anthers. This is due 

 to a difference in the pollen, which is clear yellowish green in one 

 form and reddish brown in the other. The latter colour is caused by 

 the presence of an orange colouring matter in the cytoplasm, which 

 exudes through the cell wall when the pollen is placed in alcohol 

 or water. Both types of pollen germinate, and plants with the 

 yellow type of pollen appear to be at least twice as numerous as 

 those with the orange pigment. This is of particular interest as 

 showing dimorphism in a gametophytic character. 



Leptospermuni scoparium is a polymorphic shrubby species 

 occupying vast tracts of New Zealand, with a series of forms also 

 in Tasmania and Australia. It has conspicuous white flowers 

 sometimes stained with pink. In the north of North Island 

 (Cockayne, 1907) a variety is abundant having invariably pale pink 

 flowers, the colour in the petals being confined to the base of the 

 claw. About 1897 a plant was discovered in Otago having petals 

 bright rose colour over their whole surface. This form is known 

 in commerce as L. Chapmani and is multiplied by cuttings. Later, 

 on the sandhills 200 miles from where Chapmani originated, a 

 plant with rich crimson flowers, was found. It also differed in its 

 more slender, drooping habit, darker foliage, and the flowers were 

 not terminal. From open-pollination a few seedlings like the type 

 were obtained. The evidence indicates that the polymorphism of 

 this species is due to mutation, two of the forms having already 

 established themselves as local varieties. 



Coreopsis tinctor ia Nutt.is an annual North American Composite, 

 often cultivated and escaped from gardens. It is polymorphic, 

 producing (1) dwarfs, and forms with (2) brown ray florets, (3) tubular 

 ray florets and (4) ligulate disc florets. Raciborski (1908) found 

 in an escaped colony near Lemberg a peculiar type first described 

 by Al. Braun in 1870. It has numerous adventive shoots arising 

 on the mternodes and also on the under surface of the leaves along 

 the midrib and was called var. prolifica. The seeds from such a 

 plant with brown rays yielded 84 offspring, all but 11 of which 

 showed the adventive shoots. Some of the latter were tall, some 

 short, and a few had yellow rays. Seeds of another (yellow) 

 prolifica gave 420, of which all but 16 showed the abnormality. 

 .This indicates that the abnormality is probably a recessive, the 

 normals being due to vicinism. Normal plants, however, never 

 gave seedlings with the abnormality, nor could it be produced by 

 wounding or cultivation on rich soil. 



