176 APPENDIX TO REPORT ON OYSTER CULTURE 



In conclusion, I may sum up briefly the principal conclusions to which 

 the study of the soil of oyster grounds has led me. 



1. That the influence of the soil upon the breeding and growth of 



oysters is complicated by : temperature, especially during the 

 spawning season ; sudden alternations of heat and cold, due to 

 currents ; alternation of depth of water, especially as regards 

 whether the maximum of sun-heat and light concords with low 

 water during the spawning season ; velocity of tide, angle of 

 inclination of shore, &c. 



2. That the soil of oyster ground may be made up of materials of 



any of the great classes of rocks, arenaceous, argillaceous, or cal- 

 careous, provided they contain — 



3. More or less of a fine flocculent highly hydrated silt, rich in organic 



matter, which indicates that Diatomacea, Rhizopoda, Infusoria, 

 and other minute creatures abound. 



4. That the character and abundance of such small organisms 



in a locality seems to be the true test of a successful oyster 

 ground. 



5. And lastly, that although oysters do undoubtedly assimilate 



copper from water where mine-water containing traces of that 

 metal flow into the sea in the neighbourhood of the oyster 

 beds, the copper is chiefly, if not exclusively, confined to the 

 body of the oyster, and does not appear to reach the mantle 

 or beard. That the so-called green oysters of Essex, Marennes, 

 and other places, on the other hand, are green-bearded and 

 contain no copper, nor can the most minute trace of copper 

 be detected in the soil of the oyster grounds where such 

 green-bearcled oysters are produced. 



APPENDIX I. 



Royal Commission Irish Oyster Fisheries— 12th May, 1869. 



Queries. 



1. Are there any, and if so, what description of oyster beds in this 

 division 1 



2. Where are the natural public beds situated % 



3. Are there any, and if so, what regulations enforced for throwing 

 back undersized oysters, or otherwise protecting the beds 1 and are any 

 means adopted to re-stock the public beds 1 



4. How many boats on an average in the year dredge on these public 

 beds — distinguishing the number of smacks and row boats 1 



5. How many men in each boat or smack 1 



6. How many dredges 1 



7. Is dredging carried on all the year round; and if not during what 

 months do the fishermen generally dredge 1 



8. What is the nature of the directions you received with regard to the 

 observance of close time, &c. ? 



9. When does close time commence and terminate in your locality ? 



10. Are the public beds in a declining or prosperous state 1 If the 

 former, when did the decline commence 1 



11. What, in your opinion, is the cause of the decline? 



1 2. Are there any oyster grounds in your locality used only for fat- 

 tening purposes % If so, state where situated % 



