40 J. H. MAIDEN. 



Of those enumerated by me only one species, O. inermis, 

 P. DO., is a really serious pest ; I have styled it the Pest 

 Pear of New South Wales and Queensland. It has become 

 altered by its Australian environment, and hence it does 

 not conform to the type. The evidence is too long to go 

 into at this place, but I will present it at an early date, 

 with a coloured illustration, in the Agricultural Gazette 

 of New South Wales. 



Individual plants are by no means so formidable as such 

 species as O. monacantha and O. Dillenii, but O. inermls 

 (the inapt species-name applies only to the spines and not 

 to the smaller and more troublesome spinules) has proved 

 itself fatally adaptable to the conditions of certain parts 

 of New South Wales and Queensland. Its mighty progress 

 is one of the wonders of the world in plant acclimatisation; 

 this could only happen in the broad expanse of an imperfectly 

 occupied continent. 



A few years ago experiments, extending over four 

 months, were made on Scone Common under my direction 

 (Scone holds the unenviable notoriety of being the focus 

 from which the Pest Pear spread) with the view of arriving 

 at the most economical method of destroying the plants, 

 and I recommended wounding the "bulb," the receptacle 

 for reserve material, and spraying with a solution consisting 

 of one pound of white arsenic, one pound of caustic soda 

 or two pounds of washing soda, and 20 gallons of water 

 was found useful. 



I further suggested that an independent and impartial 

 committee consisting mainly of local residents, certainly 

 not with a preponderance of government officials, should 

 be appointed to conduct experiments to ascertain (a) the 

 best poison for spraying or any other method of application, 

 (6) appliances for the application of poison, or for crushing 



