233 



Chief Inspector of Stock. The eggs are extremely resistant to 

 cold; they are laid on tlie ground in summer or Avinier. T]ie 

 larval ticks altach th(>mselves to blades of grass and lie in wait 

 for passing cattle. Having gained its host, in a week tin' larva, 

 casts its skin and emerges as an eight-legged nymph; a \\vok 

 later it moults again and emerges as a sexually mature adult. 



The result of tick-bites upon the animal is what is known as 

 tick worry, which must be distinguished from tick fever, the 

 former being due to the mechanical irritation caused by the ticks 

 and to loss of blood. Tick fever is caused by minute parasites, 

 Piroplasma higeniinum, which destroy the red blood corpuscles. 

 They are taken up by the tick when it sucks blood, and when the 

 egg laid by such a tick hatches out, the tick arising from it is 

 capable of transmitting tlie parasite to any cattle to which it may 

 fix itself. 



The methods which have been used to combat the tick consist 

 of dipping and spraying with arsenical dips. Regarding the 

 risk of dipping cattle in such poisonous dips, it is stated that 

 fatalities amongst stock dipped in properly prepared solutions, 

 under good management, seldom exceed 1 in .1,000. Cattle may 

 be safely dipped in or sprayed with an arsenical dip containing 

 an equivalent of 0'24 i)er cent, arsenic trioxide or less ; this is 

 according to experiments made in America. Inoculation against 

 tick fever is not at present practised in New South Wales, as the 

 disease is unknown there. 



Figures are given to show the cost of combating the tick in New 

 South Wales. It is stated that £20,000 is spent annually on the 

 erection of dips, establishment of salting stations, appointment 

 of inspectors, maintaining dips, etc. 



Hodge (C. F.). The Distance House-Flies, Blue-Bottles and Stable- 

 ^ Flies may travel over Water. — Science, iXeir York-, xxxviii, 

 lOtli Oct. 19i;;. pp. 512-51:1 



Plagues of flies were reported from the cribs of the water-works, 

 situated 1\, 5 and 6 miles respectively out in Lake Erie, and 

 investigations were made to find the cause. As all waste matter, 

 or anything that could serve as food for the flies, is put into 

 the lake or burned at once, it does not appear that the flies are 

 attracted by the hope of getting- food. Also it is known from 

 experiment and observation that flies do not as a rule travel 

 more than 500 yards from their breeding places, though they 

 have been known to fly for a mile and a quarter. The flies found 

 at the three cribs were house-flies (Mvscn), stable-flies (Sfomo.rjjs) 

 and blue-bottles (CaUrphora). The explanation seems to be that 

 they are blown by the wind for at least six miles and that they 

 gather on the cribs as temporary resting places. All the flies in 

 the crib appeared to be very hungry, and it should therefore not 

 be difficult to trap the house-flies and blue-bottles as fast as they 

 come. They could probably be killed most easily with 2"5 ]ier 

 cent, formalin in milk, beer, or sugar and vinegar mixture. 



