Annual Report for 1912 of the Zoologid. 291 



such parasitic diseases as " gapes," warble-fly, sheep nose-flj', 

 and sheep maggot-fly, and a considerable number of external 

 parasites of fowls and farm animals have been sent for 

 identification. One specimen received was a dead mouse, 

 obviously affected by some disease of which the sender 

 wished to know the nature. This was favus (a disease allied 

 to ringworm), due to a fungus named Achorion schoetisteinii, 

 and the case was not without importance, because human 

 beings are liable to attack, and sometimes contract the disease 

 from cats wdiich have been playing with infected mice. 



Farm and Garden Pests. 



Among the corn pests the frit-fly in oats was the most 

 prevalent. It was not only very destructive to the young 

 plant in June, but recurred, as a second brood, in the ear. 

 This second brood attack is well known on the Continent, 

 and, indeed, according to Miss Ormerod, gave rise to the name 

 "frit-fly," from the frits, or worthless grains of corn resulting 

 from it, but in England oats seldom suffer from the fly except 

 in the early stages of growth. 



Gout-fly, common enough in barley in any year, was during 

 the past season rather frequent in wheat. It is known, of 

 course, that wheat is liable to attack, but I seldom receive 

 complaints of it in that crop. The general prevalence of aphis 

 in the dry weather of early summer extended to corn crops, 

 and a case of barley failure occurred which seemed to be 

 attributable to no other cause. 



In July some sainfoin and clover crops attracted attention 

 from the fact that the heads were infested with incredible 

 numbers of yellow maggots. Examination showed these to 

 be the larvae of a midge (Cecidomyid fly), and they were 

 doubtless those of the clover seed-midge, Cecidomyia 

 leguminicola. This insect was recorded by Miss Ormerod 

 in 1890, but I am not aware that it has ever done serious 

 harm in this country. In the United States it is a well-known 

 and dreaded pest to leguminous crops grown for seed, and 

 from the cases brought to my notice last summer it was not 

 difficult to realise its potentiality for injury. In America the 

 treatment consists chiefly in cutting or feeding off infested 

 clover early, before the grubs leave the heads and enter the 

 ground to pupate. 



The root and garden crop pests inquired about included 

 celery-fly, mangold-fly, onion-fly, root maggots and various 

 species of aphis. Cases of root-knot eelworm attack in 

 cucumbers were also reported. Attention was again directed 

 to pea-thrips, though this pest did not appear to be quite so 

 prevalent as in some recent years. The history of the pea-thrips 



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