222 Forty-fifth Report on the State Museum. 



history of Tylenchus radicola which infests a large number of our 

 agricultural products, has been worked out by Professor Atkinson, 

 then of the Georgia Agricultural Experiment Station. 



The Department of Agriculture, at Washington, has also published 

 an extended report upon the Nematodes prepared by Dr. J. C. Neal, an 

 agent of the Department. 



2. The blight in the oats is probably that which has been noticed by 

 Messrs. Galloway and South worth in the Journal of Mycology, vol. vi, 

 1890, page 72. It was prevalent that year during the months of May 

 and June, in several of the United States — in some of them injuring 

 the crop from thirty-five to seventy-five per cent. Nothing in the way 

 of a fungus or animal parasite as the cause of the trouble could be 

 foimd, but bacteria were present in every specimen examined. 



The insect causing the shriveling of the oats, was the well-known 

 grain-aphis, Siphonophora avenm (Fabr.). It was not destructive 

 generally throughout the State during the year, but in two or three 

 localities it was reported as having injured the wheat crop to an extent 

 of from twenty-five to fifty per cent. 



3. For the "potato-scab," of which frequent complaints are being 

 made, no effectual preventive has as yet been found. Much attention 

 has been given to the disease, and considerable progress has been made 

 in its investigation. It appears that there are several kinds of scab, 

 resulting from different causes. It has been variously referred to 

 injuries from insects, as the wire-worm and white-grubs; to injuries 

 from millipedes (thousand-legged worms), earth-worms and mites; to 

 excessive moisture in the soil producing an abnormal growth of the 

 corky tissue; to lime or oxide of iron in the soil; to fertilization by 

 stable manure; to the action of bacteria; and to fungus attack. 



That one of the " scabs " is caused by, or at least is always associ- 

 ated with, bacteria, seems to have been demonstrated by Mr. L. H. 

 Bolley.* Another form has been found by Dr. Roland Thaxter, of 

 the Connecticut Agricultural Experiment Station, to be due to a fungus 

 attack, the particular species of which has not yet been determined.! 

 This has been named as the " deep scab," while another form, known 

 as " surface scab," often associated with it, may prove to be only a 

 modification of the former. 



4. The beneficial effect of heavy rains in destroying the elm-leaf 

 beetle, Galerucella xanthomelmna (Schrank), has not, we believe, been 

 previously reported. That such should be one of the results of heavy 



* Agricultural Science, iv, 1890, p. 243. 



fAnn. Rept. Conn. Agr. Exp. St. for 1890, pp. 81-95, figs. 1, 2. 



