v\ CEYLON MARINE BIOLOGICAL REPORTS. 



liabits, and if success is doubtful with them in their own natural surroundings, it would obviously be 

 more so here. The Mergui oyster lives in 20 fathoms on a muddy bottom, over which a 7-knot current 

 rtows. and where there is a rise and fall of 15 feet of water. Our banks are rocky, covered with only 

 an average of 8 fathoms, and bottom currents are absent. The futility of transplanting such oysters 

 is obvious. 



The Ceylon pearl banks do not require supplementuig with exotic oysters. Given a spatfall, 

 only thorough inspection, care, and normal foresight in isolating breeding stocks, &c., are required to 

 make the banks perennially productive. A spatfall is almost certain to take place at an early date, 

 and to our successors will be given the opportunity of reajiing where we have sown. 



In conclusion, I beg to express my indebtedness to the Ceylon Government for kindly publishing 

 these resiilts ; my thanks are also due to my wife, for correcting proofs and for really serious and 

 extensive help in many other ways. 



r. ^, ,^ T. SOUTHWELL. 



At Sea, Cheval Paar, 



Ceylon. November 18, 1911. 



