BY T. HARVEY JOHNSTON AND M. J. BANCROFT. 283 



ceased to be coutinnally tick infested. This grass was one 

 of the Andropogon family, the members of which are, in 

 some cases, noted for containing essential oils."' Further 

 on the same page he stated that he had a paper by Dr. 

 Nelson 8. Mayo, Cuba, 1900. in which the latter mentioned 

 certain plants that contain specifies which are fatal to ticks. 



A. K. Henderson (R.S.C., 1015, p. 43) stated 

 that for many years his farm on the Blackall Range, 6 miles 

 from Nambour, was free from ticks. This he attributed 

 to the presence of white clover. HoAV'ever, on going to 

 Maleny, several hundred feet higher, he had seen some 

 exceedingly ticky stock although white clover was gro'udng 

 luxuriantly there. After this experience he had not placed 

 much reliance on the clover theory. It is stated {Q.A.J., 

 vol. xix, 1907, p. 142) that it has been found on the Blackall 

 Range that in paddocks projierly cleared and laid down with 

 paspaluui, ticks do not breed to the same extent that they 

 do in rough uncleared country. 



Notice appeared (Q.A.J. , vol. iv., 1899, p. 498) of a 

 particularly ticky cow in the Cairns district being rendered 

 tick resistant by feeding with saltpetre and salt. P. R. 

 Gordon (same issue) stated that the matter had been 

 investigated by Sir Horace Tozer and quantities of saltpetre 

 were tried on cattle without the slightest effect. 



In several communications and in an interview JSIr. 

 L. G. Jones stated his conviction that food plays an aU- 

 important part in an animal's susceptibi'itj^ to tick infest- 

 ation. Whilst animals graze on lucerne or paspalum 

 (P. diJatatum) the}' remain resistant to the tick until they 

 are turned on to a poorer pasture. Mr. Jones pointed out 

 the impracticability of substituting artificial grasses or 

 lucerne for natural grasses on a large scale. He furnished 

 us \\-ith a copy of analyses of paspalum and ordinary' 

 pasture shewing the higher percentage of inorganic matter 

 contained in the former. The percentage of sulphates and 

 chlorine and soda was approximatel}' twice as great, Avhile 

 that of ferric oxide and potash was from 3-4 times as great 

 in paspalum as in ordinary grass. Mi\ Jones gave us the 

 result of some obser"\'ations and experiments performed 

 on sheep in N.S.W. which point to the efficacy of certain 

 iron ore and salt mixtures in helping sheep to withstand the 



