152 
MASSACHUSETTS HORTICULTURAL SOCIETY. 
From one to two hundred of this larva were frequently taken from a sin¬ 
gle gizzard, all in a fresh, unmacerated condition; and usually, when this 
larva was found, it was the only food in the stomach. 
To quote from a communication received from Dr. Fitch, he says, “ My 
attention was first directed to this fly some twelve years ago, when I was 
occupied in investigating the wheat midge. I observed it to be so very 
common in fields of growing wheat that I suspected it of living at the ex¬ 
pense of that grain crop ; but on looking around I found it was equally as 
common everywhere else — resting upon the grass, leaves, and flowers in 
my yard and garden, as well as in meadows, pastures, and forests * * * * * 
It comes abroad about the 20th of May, and continues about a fortnight. 
You will readily recognize it by its commonness, and its white transparent 
wings; its body being black, clothed with soft white hairs. It is very sluggish, 
moving around but little, and is easily picked up by the fingers. ***** 
On page 764 of the London Gardener’s Chronicle of the year 1844, is a 
valuable article of Ruricola, (J. O. Westwood,) giving a full history of 
the Bihio Marci, the European analogue of the one in question. ‘ It 
appears these insects (unlike most others of the family Tipulidte to which 
they pertain) are most pernicious, the larva feeding upon the roots of 
plants, sometimes to such an extent as to cause them to wither and die. 
Ruricola states that the larva of the Marci, and other allied species of 
Bibio, are frequently sent to him by gardeners, who find them to be mis¬ 
chievous in their strawberry beds, vine borders, flower pots, and other situ- 
tions where the soil remains undisturbed during the autumn and spring.’ 
And another writer, Bouche, says ‘ that his bed of ranunculuses was com¬ 
pletely demolished, for several successive years, by these worms eating the 
roots.’ From these facts every one will perceive that the robin, consum¬ 
ing, as you found it to do, from one to two hundred of these Bibio larva 
daily, during the months of March and April, has probably been ridding 
our gardens of these vermin every year hitherto; thus rendering us an im¬ 
portant service, of which we have been wholly unaware. ***** The 
larva are gregarious; living together in swarms, and perforating the ground 
so that it resembles a honeycomb. 
This is probably caused by the parent fly depositing her whole stock of 
eggs in one spot, she being too lazy and slothful to wander about and dis¬ 
tribute them in different places. Hence the robin, on finding one of these 
worms, knows that there is a host of others at the same place, and thus re¬ 
pairs to that spot, day after day, and gluts himself with them till the whole 
colony is exterminated.” 
