TRANSACTIONS OF SECTION D. 723 



that the Universities have neither the means, the ships, nor the experienced staff 

 distributed along the coast line and iu constant touch with the subject, for 

 efficiently dealing with it. A public department alone is capable of undertaking 

 it with success, as the practice of other nations from America to Japan abun"- 

 dantly testifies. 



2. On the Royal Duhlin Society's Fisliery Survey. 

 By Professor A. C. Haddon. 



3. On the Fishery School at Ringsend, near Duhlin. 

 By Professor A. C. Haddon. 



4. Oyster Cultural Methods, Experiments and New Proposals. 

 By Bashford Dean, Assistant U.S. Fishery Commission. 



The author spoke of the difficulties in spat collecting, and of some recent sug- 

 gestions as to their obviation ; of the lack of delinite knowledge as to the most 

 favourable physical conditions of the oyster's set ; of questions of aeration, density, 

 temperature, and silt deposit of the water during the spawning season. He referred 

 to the difficulty in retaining the embryos in bcnsins and in determining the duration 

 of the motile stage. The suggestiveness of the mare piccolo and of the closed 

 lake of Brineguy .- the experiments in spat collecting of Eice, Saint-Sauveur, and 

 more recent culturists, and the possible defects of the cultural methods lately 

 patented in tlie Urdted States were also discussed. 



5. On Oysters and Typhoid: an experimented Inquiry into the effect ujwn 

 the Oyster of various external conditions, including Pathogenic Organ- 

 isms. By RuBERT W. BoYCE, M.B., M.R.C.S., Professor of Pathology 

 in University College, Liverpool ; and W. A. Herdman, D.Sc, F.R.S., 

 Professor of Zoology in University College, Liverpool. 



Our motives in undertaking this investigation liave been — 



1. Purely scientific— the elucidation of the life conditions of the oyster, both 

 under normal and abnormal environment. 



_ 2. Economic or technological— to trace the causes and eflTects of diseased con- 

 ditions, with the view of determining what basis exists for the recent 'Oyster and 

 typhoid ' scare, (a) in the interests of the oyster fisheries, and {h) in the interests of 

 the general public. 



A. The objects, in detail, we had in view in entering on the investigation were 

 as follows : — 



1. To determine the conditions of life and health and growth of the oyster by 

 keeping samples in sea waters of difl'erent composition— e.r/. it is a matter of dis- 

 cussion amongst 1:)ractical ostreiculturists as to what specific gravity or salinity of 

 water, and what amount of lime are best for the due proportionate growth of both 

 shell and body. 



2. To determine the eflect of feeding oysters on various substances — both 

 natural food such as Diatoms, and artificial food such as oatmeal. Here, again, 

 there is a want of agreement at present as to the benefit or otherwise of feeding 

 oysters in captivity. 



3 To determine the eflfect of adding various impurities to the water in which 

 the oysters are grown, and especially the efl'ect of sewage in various quantities. It 

 is notorious that oysters are sometimes grown or laid down for fattening purposes 



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