MISCELLANEOUS NOTES 285 



Those estates where bad pruning, bad drainage, &c., prevail, 

 and where " pick, pick, and keep on picking " is the first 

 order of the day, will most assuredly be those which will 

 afford no encouragement to the planter. It may be 

 mentioned that Diplodia, though better known than 

 Lasiodiplodia, is still placed by some authors also among 

 Fungi imperfecti, and it is to be understood that there is 

 much more to be learned about its history and habits than 

 has yet appeared. Since beginning this work, we have 

 seen Diplodia on the grape-vines and on grains of corn, 

 and literature shows that in Europe species of it attack 

 the holly, lilac, chestnut, mulberry, and various conifers. 

 It is also reported to attack the avocado pear, the sugar 

 cane, and the mango. It may be mentioned that the 

 distinction made by various authors in regard to generic 

 characters which distinguish Diplodia, Botrio diplodia, and 

 Lasiodiplodia has not as yet removed them from the class 

 known as Fungi imperfecti, or those which are imperfectly 

 known. More recent observations appear to afford 

 evidence that Botriodiplodia, Lasiodiplodia, and Chceto- 

 diplodia are merely forms of Diplodia cacaoicola P. Henn. 



Insect Attack on Plants. — Practically there are few 

 " cures " for the destruction of insects which can be applied 

 without damage to the host which is attacked, be it more 

 or less visible or invisible, noticeable or unnoticeable. 



In many cases the observer or cultivator is apt to con- 

 clude too prematurely that no damage is done by sprays 

 or washes, a conclusion which " after-practice " may show 

 to be quite erroneous, as discussed under " Spraying." 

 That damage can be done, and has often been done, by 

 such applications has been frequently proved, and therefore 

 other and safer means would certainly be used were such 

 means available and known to the cultivator. 



The most natural of all methods for controlling the 

 spread of insects is that found in the discovery of the 

 natural enemies of the obnoxious insect, which are harmless 

 to the plant attacked. We know that many of the common 

 coccids, or scale insects, are destroyed by parasitic fungi 



