ACACIA SEEDLINGS. 



105 



ACACIA SEEDLINGS, Part VII. 

 By R. H. Cambage, f.l.s. 



[With Plates II - V.] 



[Read before the Royal Society of N.S. Wales, August 3, 1921. .] 



SYNOPSIS : 

 Vitality of Seeds in Sea-Water. 

 Rapid Germination, 



Sequence in the Development of Leaves. 

 Number of Pinnae on One Leaf. 

 Closing Up of Phyllodes at Night. 

 Flowering Seedlings. 

 Description of Seedlings. 



Vitality of Seeds in Sea-Water. 



A seed of Acacia melanoxyloii from Jenolan Caves ger- 

 minated when planted after having been immersed in sea- 

 water 4 years and 1 month. This constitutes a record for 

 this experiment so far as I am aware. 



Rapid Germination. 

 During these experiments it has been noted that seeds of 

 Acacia pendula and A. Osivaldi germinate very rapidly 

 after being placed in hot water and planted, and that both 

 species produce fleshy cotyledons. They, especially the 

 latter, will grow in hot districts with a low rainfall, and 

 in many instances may germinate as the result of a thunder- 

 storm. It would seem, therefore, that this character of 

 speedy germination may have developed to allow the young 

 plants to become established quickly after a rain storm and 

 before the ground again becomes dried up as often happens 

 in the far interior. 



