124 THE DATE PALM. 



also, long yellow hyphse are developed which protrude from 

 the pustule at first like hairs from a tiny paint brush and later 

 become more spreading (see illustration No. 42, Figs. 1-2). 

 Large numbers of the spores adhere to the sides of these long 

 hyphse (see illustration No. 42, Fig. 4), and are carried with them 

 out of the sporocarp to the open air, where wind, insects, etc., 

 may convey them to other leaves or plants, there to germinate 

 and start a new centre of the disease. The hard outer black wall 

 of the sporocarp protects the developing spores inside, and is 

 left standing on the leaf after the long brush-like hyphse and spores 

 have disappeared (see illustration No. 42, Fig. 3). A micros- 

 cope magnifying over 60 diameters is required to distinguish 

 the spores and a magnification of over 300 diameters is 

 required to see them well. The long hyphse protruding from the 

 sporocarp when they are present, and the sporocarp itself, are 

 seen by the naked eye but are better examined with a pocket 

 lens. 



As old leaves very naturally become worst affected the trees 

 should be kept properly pruned (see illustration 



Remedial measures. 



No. 29, page 86a). Spraying with a solution of 

 permanganate of potash or with Bordeaux mixture are recommen- 

 ded by those who have found it necessary to control the disease. 

 Bordeaux mixture gives excellent results against many fungoid 

 diseases. 



The mixture consists of copper sulphate (CuS0 4 ) and quick- 

 Bordeaux mixture, lime (CaO). 



The quantities generally used are 6 seers of copper sulphate 

 and 4 seers of quicklime in 50 gallons (12J kerosene tinfuls) of 

 water. 



The copper sulphate should be as good and pure as possible ; 

 copper sulphate containing a large amount of iron or of zinc 

 sulphate should not be used. 



The lime should also be as pure as possible and should be 

 freshly burnt. 



