20 



CEYLON PEARL OYSTER REPORT. 



" The sizes of average samples from the three sections of the West Cheval are as 

 follows : 



" Some exceptionally fine oysters from a patch at the extreme south end of the 

 Mid-west, a patch lying upon sandy bottom, rose to the high average dimensions of 

 76*56 millims. by 69 - 16 millims. by 34*44 millims. If we exclude the last-mentioned 

 oysters as being exceptional, we get as the general average of the 4^ to 4f-year-old 

 oysters fished this year 73*79 millims. by 66*98 millims. by 31 "86 millims. 



"During the course of last year's fishery (1903) I found the average size 

 characteristic of oysters on the Eastern Cheval to be 75*51 millims. by 69*18 millims. 

 by 31*18 millims. Both lots originated from the same brood, and it is significant that, 

 although this year's oysters are a full year older, their size, except in respect of 

 breadth, is decidedly inferior to the average of those fished last year from the 

 Eastern Cheval. This marked character, due to stunted growth, has long been 

 associated with oysters from this particular region, and has frequently been referred 

 to by Sir William Twynam and by Captain Donnan. Occasionally this stunted 

 growth has been so extreme that the divers and merchants have referred to such 

 oysters as being of the ' Kottapakku' variety, a form which is undoubtedly correlated 

 with overcrowding on extensive stretches of rocky bottom." 



Number, Distribution, and Sizes of the Immature Oysters. 



" Immense quantities of immature oysters varying from 2|- to 2^ years old covered 

 practically the whole space on the eastern half of the Mid and North-west sections, 

 extending eastwards into the North-central, Central, and South-central areas. The 

 South and the South-east Cheval also bear very large quantities, as do also the North 

 and South Modragams. 



" A fair-sized bed, plentifully covered with oysters, is at present on the Dutch 

 Modragam Paar, but they are too young to fish for at least a year, as the age of the 

 majority varies from 2 to 2^- years. These oysters represent the young spat which 

 was noted as abundant in November, 1902 ; their growth has been at the expense of 

 the older oysters that were present that year, and which have been killed off by the 

 more vigorous and numerous young. 



' The size of those on the North and South Modragam paars and those on the 

 South, South-east, and South-central Cheval, is greater than that of those upon the 



