SCIENCE AND INDUSTRY. 
The larve, or “seed ticks,” which hatch out must gain access to a 
suitable host or they will die. They are, however, very tenacious of 
life, especially when they can obtain shelter from unfavorable weather. 
In our experimental plots they were not given an opportunity to infest 
an animal, and it was found that all the larve from any particular 
batch of eggs had died after a starvation of from four to six months 
during summer or winter. Thus, if cattle, horses, &., be kept out of 
an infested paddock for six months, such paddock will probably become 
free from seed ticks, provided that larvee be not introduced mechanically 
by water or by various birds and animals. 
Should the larve reach a suitable host, they undergo a series of 
moults to become eight-legged nymphs and adults, the period between 
infestation and the dropping of the engorged (i.e., egg-laden) female 
being generally about 21 to 24 days. Assuming that a female tick 
dropped from an ox on 1st October, and that the larve from the eggs 
laid gained access to cattle immediately on hatching, then between that 
date and tst June following at least five generations would have made 
their appearance, and possibly many millions of ticks produced from 
that one tick. Of course, there are many checks against such enormous 
numbers developing to maturity—e.g., activities of birds, effect of 
weather, failure to gain access to suitable host, failure of eggs to 
hatch, &e. 
The influence of weather is very great: The effect on the hatching 
period and on the non-parasitic life of the larve has already been 
alluded to. In those districts of Queensland where heavy frosts oceur 
the tick appears to have been, as yet, unable to establish itself. Cold 
winter nights, even if the temperature be not low enough for frosts, 
profoundly affect the egg and larve, death being a common result, 
while a retardation of the development of the larve within the egg will 
certainly occur should death not take place. Then, again, the female, 
after dropping from the beast, lives much longer on the ground during 
winter than in summer, and distributes her egg-laying in an irregular 
manner over a much greater length of time. Such eggs may be so 
retarded in their development that they (or a small percentage of them) 
hatch out in the succeeding spring and infest cattle. Under favorable 
conditions of warmth and moisture, practically all the eggs laid (90 to 
98 per cent.) hatch out. Hot, dry weather has a very detrimental 
effect on the egg development; very few larve being produced under 
such conditions. ' 
Drsrases Propucrep rx Ausrratta. 
There are two diseases, viz., tick fever, or redwater, and tick worry, 
or tick poverty, caused by tick infestation. 
Tick fever, or piroplasmosis, is caused by a minute animal parasite 
called Babesia (or Piroplasma) bigemina, which is inoculated into the 
blood of cattle by the bite of an infected tick, especially in the larval 
stage. The organisms invade the red blood corpuscles, develop and 
reproduce at their expense, ultimately causing their destruction with 
resulting fever and liberation of blood pigment, which is eventually 
excreted by the kidneys. When this blood constituent—so important 
as the oxygen carrier of the blood, is voided in quantity, then the urine 
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