90 SJiorf Stf))iina)')/ of our Knoirleilgt of tin' Frit-Jin 



writers on the Continent as attacking only rye in the winter generation 

 and only the panicles of oats in the summer generation, whereas these 

 generations oi frit are recorded as not being so particular as to the object 

 attacked. 



PARASITES. 



Sigalfhus caudalus (Curtis, 1 8G0) ; Pteromalus pupariun, P. tnicans, a,nd 

 SigaJpJins caudatns (Rorig, 1893); Rhoptomeris wildhami Kour. and 

 Trichomanus crisfatus Forst. (Baranov, 1912); Polyscytns oscinulis Kurd, 

 sp. n. (Mokrzecki, 1913); Mersius intermedins and SemiofeJhis nigripes 

 Lindni. (Wilhelm. 1891); Miris dolobratvs and Plernmahis nncans 

 (Schesterikov, 1910); Coccinellidae destroy the larvae (Wilhelm, 1891, 

 Rorig, 1893 and Schesterikov, 1910), and an unclassified entomophagous 

 fungus kills considerable numbers (Schesterikov, 1910). 



Dobrovliansky (1913) found that in barley sown on May 21st in 

 the Government of Kiev, 21 per cent, of the pupae of/>// were parasitised, 

 and on oats sown July llth 16 per cent, of the pupae were parasitised. 



RESISTANCE TO ATTACK OF DIFFERENT VARIETIES OF CORN. 



Very indefinite conclusions have been arrived at on this point. 

 Kulagin (1913, Russia) recorded "Triumph"" oats and naked barleys 

 as suffering most. Rorig (1893, Germany) said that experiments appar- 

 ently showed that "'Triumph" and other "bearded oats" [Fahnenhafer) 

 were less attacked. Aurivillius (1892, Sweden) came to the conclusion 

 that "six-rowed"" barleys were much more liable to attack than "two- 

 rowed" barleys. McDougall (1912) found that in Scotland "Hamilton" 

 and "Potato" oats were least damaged, followed by "Sandy,"' "Wide- 

 Awake" and "Abundance," while "Tartar King," "Beseler"' and 

 "Banner" were very badly attacked ; this would appear to support the 

 view that those oats that tiller freely are better able to stand against 

 attacks of frit-fly than those that do not. 



In the Report on the breaking up of grass land in 1916-1 7, published 

 by the Board of Agriculture in 1917 as Mis-rellaneous Pi'hiications, 

 No. 19, a case is recorded from Yorkshire where two varieties, '* Bountiful "' 

 and "Beseler's Prolific," were sown in April on a ten acre field which 

 had been broken up in Februury. "Bountiful"" i)rovided an excellent 

 crop of 7 qrs. per acre, l)ut "Beseler's Prolific" suflereil greatly from 

 frit-fly and was a much lighter crop. 



Ritzema Bos (1891) I'ccorded some observations on a number of 

 varieties in Holland in which he found that "Longfellow," "White 

 Canadian," "Black Canadian" and "Early Blossom" exhibited con- 

 sidci'iibli' powci's of I'csisfjuice. 



