240 



SPOLIA ZEYLANICA. 



Appendix 4. — Growth-rate of First-year Oysters in various parts of 

 the Beds during 1912. 



(The areas are given iii order of rate of increase. In some areas 



measurements were taken in September only, and in these 



no rate of growth can be given.) 



Rate of 

 Increase in 

 September. 



•44 

 •17 

 •02 

 •86 

 •77 

 •74 

 •71 

 •57 

 •53 

 •45 



•77 



Relative Abund- 

 ance of Oysters 

 (Approximate). 



Very scarce 

 Very scarce 

 Very abundant 

 Scarce 

 Abundant 

 Abundant 

 Abundant 

 Very scarce 

 Very scarce 

 Very abundant 



Fairly abundant 



Appendix 5. — Measurements of First-year Oysters, May, 1912. 



(See also Plate 6.) 



Size (Hinge 



Diameter). 



Inches. 



2f 

 2* 

 2| 

 2|- 



9 7. 



3 



Total oysters 



No. of 

 Specimens. 



5 

 20 

 11 

 10 



4 



3 



122 



Appendix 6. — Measurements of First-year Oysters, June, 1912. 



(See also Plate 7.) 



Size (Hinge 



Diameter). 



Inches. 



H 

 H- 

 H 



4 

 Total oysters 



No. of 

 Specimens. 



15 



25 



4 



10 



2 

 6 



287 



