42 



previously suggested, the destruction of sucli unwelcome 

 intruders may be very readily effected. ^'Drills'* and 

 boring sponges are naturally to be tliougiit of as types 

 which should be destroyed, while diatoms, infusoria, 

 small polyps, bryozoa, minute algae, etc., are to be 

 favored in every way. Those forms again, which the 

 oyster culturist knows are there only for the purpose of 

 getting a good living with little trouble to themselves, 

 ought to be destroyed. 



It might be an advantage to introduce certain desirable 

 forms onto a bank, which might be supposed to be use- 

 ful as a food supply. Infusoria and diatoms not pre- 

 viously existing might be introduced in this way ; this, 

 I think, would be especially easy in the case of the for- 

 mer vrhere the type was one which is fixed during its 

 adult life. 



METHODS OF OOLLECTIIS^G AiS^D COLLECTING APPAEATFS. 



Not having reached the field until the 19th of July, I 

 did not succeed in testing the various collectors, which 

 were for the most part modelled after those in use in 

 France, as thoroua-hlv as I desired. Roofing slates, tiles, 

 shingles, oyster shells and pine cones were used to afford 

 attachment to the young fry of the oyster : in all cases the 

 apparatus was of course submerged, but was not allowed 

 to sink low enough so as to be in contact with or par- 

 tially buried in the mud. The most successful apparatus 

 used was the various modifications of the slate collector, 

 and which in practice will probably be found the most 

 satisfactory in the long run. We first coated the slates 

 with a mixture of lime and sand, mixed in sea- water, thick 

 enough to cover the surfaces when dipx3ed into the mix 

 ture with a x)retty thick layer : an eighth of an inch is 

 not too much, so that when the young fry has attained 

 a considerable size it may be removed without injury 

 along with the coating of mortar, a method first intro- 

 duced in Europe by Br. Kernmerer, though he used 



