382 



MA\i;ROVE and SALTMARSH vegetation XEAI! SYDXEY, N.S.W., 



The writer has observed various stages in the emergence and establishment 

 of the young seedling of Aegiceras. The seedling drops to the mud, still en- 

 closed within the thin brown pericarp of the fruit. It is not in such an ad- 

 vanced state as that of Avicennia. The hypocotyl is pronounced, gi-een in colour 

 and curved at the end from which the radicle is destined to develop. A pair or 

 small gi-een cotyledons are just discernible at the tip of the hypocotyl. After 

 a time the pericarp splits and tlie curved jjortion of tlie hypocotyl elongates 

 towards the mud (Text-figs. 7-9). The hypocotyl continues to grow and at 

 length a thin colourless primary root penetrates the mud, from which secondai-y 

 roots are given off later. In the meantime the pericarp has split again to 



Text figs. 710. Various stages in the establishment of the viviparous seedling of 

 Aegiceras inajus. 



allow the escape of the cotyledonary region and the plumule. The seedhug 

 becomes erect and the short e))i<'(ityl and first true leaves make theii- appearance 

 the only trace of the original curvature of seedling being found where the root 

 enters the mud. With the elongatitm of the seedling, the pericarp is carried 

 some distance above the mud (Text-fig. ll>), but after a time it decays and drops 

 to the ground. 



