380 



MANGROVE AND SAI.TMAKSll VEIJETATION NEAR SYDNEY, N.S.W., 



phores spring from long horizontal roots which radiate from the hase of the 

 tree, and are to be found at no great depth below tlie surface of the mud (Texi- 

 fig. 5, and PI. xxix., Photo 8). This horizontal growth of the root system of 

 Avicennia helps to consolidate the mud and prepare it for later colonisers. 



Textfigs. 2-4. Viviparous seedlings of Avicetinia officinalis. 



Attached to parent plant and still enclosed within pericarp. 3. After rupture 

 of pericarp and showing estabHshment of seedhng on mud; note circlet 

 of hairs at base of hypocotyl and first roots projecting. 4. Later stage 

 of establishment, where numerous roots have developed at base of hypo- 

 cotyl and are taking up horizontal position on mud. 



Aeijlceru-t majim is by no means as constant a feature of mangrove forma- 

 tion near Sydney a.s is Avicennia officinalis. The former apjiarently reaches its 

 southernmost limits on the coa-st of New South Wales, possil)ly at (^abbage Tree 

 Creek, Port Hacking, to be described later. Aeyieeras occupies the iinicmiost 

 limits of mangrove formation and is in striking contra.st to Avioeiiiiia officinalis 

 (Plate xxvii.. Photo 4). It grows erect, and is, at most, a tall shrub (PI. xxviii.. 

 Photo 5). Its average height near Sydney is about six feet. Its glo.ssy green 

 foliage stands out vividly against the grey-gi'cen of Avicennia, as do also its 

 red, tannin-bearing l)ranches against the ashy grey, lichen-coated trunks of 

 Avicennia. The leaves of Aerjiceras ma jus- are remarkalilo in early morning for 



