THE AUSTRALIAN GREY MANGROVE. 277 



The Madras Report for 1895-96, states: — "It was found 

 in the Kistna District that the annual growth in diameter 

 of the mangrove (Avicennia) amounts to nearly an inch, 

 and from one to two feet in height. It is considered the 

 spurious rings are monthly, and are probably due to the 

 different conditions of nutrition caused by the spring and 

 neap tides." 



Perhaps the tropical temperatures may cause such rapid 

 growth, but such a rate does not hold for the New South 

 Wales plants. Mr. Dick is a keen observer of nature, so 

 that his data should not be despised, and having visited the 

 locality and examined the tree in situ, I think he is correct 

 in his decisions (infra). 



From observations made by Mr. Dick on the species 

 occurring at Port Macquare, the monthly rate of growth 

 obtained by Mr. Lushiogton does not hold in Australia, in 

 fact, it appears that a very slow rate of growth obtains in 

 this country. 



Port Macquarie in New South Wales is an important 

 centre of oyster cultivation, and this particular mangrove 

 is much used in the culture of that mollusc, so that the tree 

 has necessarily been under close observation by many 

 people for a long time. Mr. Dick writes me in this con- 

 nection : — 



" I have been for a number of years on this river, and working 

 amongst the Mangrove, and I am in a position after my experience 

 of twenty-five years to state that this tree has a very slow rate of 

 growth. Other people, who have been for sixty years in the same 

 locality, also state that the tree has a very slow growth, and that 

 it is not noticeable, being *so very, very slow. I, to-day, went 

 to certain trees that had been marked in reference to the fixing of 

 the boundaries of certain of our oyster leases, this marking having 

 been done in 1897 ; one tree had the broad arrow cut in it, the 

 number of the lease also. Now on examination to-day, the marks 

 are not much altered, and are not overgrown in any way. A 



