I. AGRICULTURE AND RURAL ECONOMY. 353 



ingly carried out, it is profitable, and that there is much to 

 encourage an enterprise of the kind. It also states that Ire- 

 land possesses external advantages for the culture, on account 

 of the feeding process being attended with so little risk, and 

 thinks that ten times the amount of oysters now actually 

 gathered in Ireland could find a ready sale. A summary of 

 the principal laws relating to oyster culture in different coun- 

 tries of Europe, with tables of temperatures and other infor- 

 mation, concludes the report, which is well illustrated with 

 drawings of the oyster in its different stages of growth, and 

 plans of the localities where the business of oyster raising is 

 prosecuted. 



GRAPE-YIXE DISEASE. 



Most of our readers are aware of the outbreak of a new 

 grape-vine disease in Europe produced by a kind of plant- 

 louse, which, spreading from one region to another, threatens 

 to almost paralyze the cultivation of that plant; but the fact 

 is probably not generally understood that the pest in question 

 is a native of the United States, and has been transplanted to 

 the Old World, with the result referred to. Mr. Riley, the 

 State Entomologist of Missouri, has lately published in the 

 Mural New Yorker several articles on the subject, in which 

 he discusses the history of this insect, showing that the first 

 reference to it was by Dr. Fitch, of New York, in 1856 (who 

 called it Pemphigus vitifolia), Mr. Riley himself writing about 

 it in the Prairie Farmer in 1866, and succeeding articles also 

 appearing by Mr. Shinier and Mr. Walsh. After this it. at- 

 tracted attention in the south of France, where its ravages 

 became so great that the Minister of Agriculture offered a 

 prize of $4000 for the discovery of a practical remedy. A 

 special committee was nominated to investigate the whole 

 subject, and the history of the insect has since that time be- 

 come pretty well understood. 



Referring to Mr. Riley's papers and other sources for the 

 details in regard to the natural history of this pest, we may 

 simply repeat the statement of this author, that it is to the 

 presence of this insect in our soil that we owe the great diffi- 

 culty in raising the European grape in America, as also some 

 of the varieties of our own native species. It is found by ex- 

 periment that certain kinds of vines are more liable to the 



