TRANSACTIONS OF SECTION D. 423 
damp wool were suitable, and though the sheep with the thickest fleeces and 
wrinkled skins are the most susceptible, no class or breed of sheep is exempt in 
a bad fly year. Ewes, too, were the first that suffered, but it was soon evident 
that both sexes were liable to infestation if weather conditions were favourable 
and flies abundant. Wethers are blown anywhere if dirty or damp, and lambs 
after tailing and marking are often so badly blown that a certain percentage die 
despite the greatest care; while on the large holdings in Central Queensland, 
where the system of marking is more rough and ready, thousands of lambs, 
particularly wether lambs, are blown, and in some cases might be said to be 
eaten alive. Rams, though they often get ‘ maggoty heads’ from the after-results 
of fighting, were the last to be attacked on the body wool. But it is now quite 
a common thing to find a number of stud rams badly blown about the crutch, 
and the maggots swarming on the wool of the rump. 
Where sheep are not examined constantly, and get even slightly blown, the 
infested area soon spreads, as other flies, attracted by the scent, keep on blowing 
round the evil-smelling heated wool. As these maggots increase in size they work 
their way down through the fibre of the wool, and, through their presence, cause 
the wool to become a blackened putrid mass of corruption. Finally the maggots 
reach the skin, where they set up an inflammation of the cuticle. The broken 
skin suppurates and the detached wool is torn off, or falls off. Under such 
conditions the sheep often wanders away from the flock into the scrub, and 
dies ; the more robust ones recover. 
In all the first samples of blown wool, whether received from the sheep- 
owners or taken direct from sheep in the paddocks, the writer only bred one 
species of blow-fly. This was the common brown and yellow blow-fly (Calliphora 
villosa), found both in the town and country, a carrion-feeder ranging all over 
Australia. An unusual increase in the numbers of this species was probably 
due to several causes; in the first instance to the enormous number of dead 
animals, particularly sheep, that had died during the great drought a few years 
before, and which, not worth skinning, usually remained covered with decaying 
skin and wool. This was also the time when hundreds of thousands of poisoned 
rabbits were festering all over the pastoral holdings—ideal carrion for the blow- 
flies. The next factor was the production of a new class of merino sheep, to 
replace the smaller smooth-bodied animals, quite a different type of larger size, 
closer wool, wrinkled skin, and heavy yoke all through the fine wool, much 
more easily soiled with urine and excreta. 
With the return of the good seasons the supply of carrion vanished, but the 
blow-flies remained. Some had blown the dead wool, and recognised the smell 
of fouled wool, and thus Calliphora villosa became a sheep-maggot-fly. Within 
the year numbers of a second species of blow-fly emerged from samples of 
infested wool which had been sent in from the country, and placed in the 
breeding jars. Though the maggots were very similar, it was a very distinct 
species, Calliphora oceanie, easily distinguished from the first species by its 
smaller size, and the colouration of the abdominal segments, which, instead of 
being golden, have the sides blotched with yellow, and the rest deep metallic 
blue. The range and habits of both species are identical, and as they are 
frequently found together it is only reasonable to suppose that Calliphora 
oceanice learnt the habit of blowing wool from Calliphora villosa. 
For several years only these two species were found in the larval state among 
blown wool. Though there were reports from sheep-owners that a third species 
was infesting the sheep, and that a dark-coloured ‘hairy’ maggot was busy 
among the wool in the western country, it was not until late in 1909 that speci- 
mens of the third blow-fly, Calliphora rufifacies, was obtained direct from blown 
wool. There was no mistaking this smaller metallic blue and green fly: the 
parent of the ‘hairy maggot.’ While both the previous species produce the 
typical elongate cylindrical maggot, Calliphora rufifacies is a shorter thickened 
larva having each segment ringed with a band of fleshy filaments, which have 
given it the popular name in the bush of the ‘hairy maggot’ or ‘ hairy maggot- 
fly.’ Though now extending its range, until very lately this fly was not found 
in the coastal districts, but was confined to the inland districts of Australia. 
Before Calliphora rufifacies learnt the habit of blowing live wool, presumably 
through the smell of the wool infected by the other two species, it was a carrion- 
