16 



64. The patch was isolated and of small extent, some 8 feet long by 

 4 feet wide. The foundation or core consisted of dead oyster shells mostly of 

 very large dimensions and of characteristically elongated form true " slipper- 

 oysters." These were more or less embedded in the mud ; upon their upper 

 edges were a considerable number of living oysters much younger and of more 

 irregular growth than the dead ones beneath. A distinct tendency to broaden 

 was noticeable due to the fact that the higher clumps of old oysters whereon 

 they were seated were sufficiently elevated to free the living generation in large 

 measure from that pressing necessity imposed on earlier generations to concen- 

 trate growth in an upward direction in order to avoid death through sinking 

 beneath the surface of the mud ; the death of several preceding generations has 

 produced a plateau-like mass of shell concrete providing comparatively stable 

 foothold for any brood which may now settle there. 



Bare mud flat 

 Overflowed -sf 

 high sprinq tides. 



Bare rrwd flat 



with an occasional 

 msfiqrove bush. 



oyster 

 patch. 



Mall Creek. 



Plan of small creek opening into Mall Creek, to show 

 location of ojster patch referred to in the text. 



The average size was about 3| by 2| inches ; judging from what I know of 

 the growth of oysters under tropical conditions they appear to be under two 

 years old. This estimation was confirmed by Mr. Judd's statement that two years 

 previously this patch was completely cleared of saleable oysters and left as a 

 bed of dead shells. Since then this and neighbouring creeks have been closed 

 to fishing, hence the mature living oysters seen here have grown up within this 

 2 years rest. A fair number of Balanm and Anomia were present on the 

 oysters, the former very small, the latter from to 1^ inch in diameter. 



65. On our return later in the day we saw four men collecting oysters 

 from this patch ; they were finishing and had gathered practically every sizeable 

 oyster. These were laid in a heap on the bank ready to load into their boat. 

 The creeks had been re-opened to fishing a few days previous and the day of 

 our visit was the first day this patch had been touched for two years. As I 

 wrote in my notes at the time, " It will also be the last for a long time as 

 there were not halfa-dozen living oysters left when these men finished. The 

 bed has been cleared right out." 



