262 The Philippine Journal of Science i9i8 



The above is the usual formula for formalin. The amount of 

 water used varies with the use to which the solution is put and 

 with the length of treatment. Use as directed in special cases. 



CORROSIVE SUBLIMATE 



Corrosive sublimate is a strong disinfectant that is used for 

 treatment of seeds or of vegetative reproductive parts and the 

 disinfection of agricultural implements used in the eradica- 

 tion of diseased plants. Corrosive sublimate is a deadly poison 

 to man and animals and should be labeled poison. Plants treated 

 with this solution should not be used for human food or be fed 

 to animals. 



Materials. Deadly poisonous to animals. 



Corrosive sublimate crystals, grams 112 



Water, liters 114 



PREPARATION 



Dissolve the corrosive sublimate in from 2 to 4 liters of hot 

 water and dilute this strong solution with water to make 114 

 liters. 



Seeds treated should be thoroughly washed after applying the 

 preparation and planted at once. 



SPRAYING APPARATUS 



For spraying operations conducted on a small scale a bucket 

 pump or a knapsack pump will serve the purpose (Plate XXII, 

 figs. 1, 2, and 3). Pumps of this character cost from 7 to 10 

 pesos for bucket pumps and from 20 to 40 pesos for knapsack 

 pumps. Where extensive spraying operations are undertaken 

 it will be necessary to employ a good pressure barrel pump 

 (Plate XXII, fig. 4). The latter spraying outfit does the work 

 more efficiently and in less time. The cost varies from 45 to 

 100 pesos, including hose and nozzle. 



A good nozzle is essential in order to obtain the best results. 

 Such a nozzle will produce a fine mist and cover the plant evenly 

 over the portion sprayed. There are many spray outfits on the 

 market. In purchasing a particular outfit, one should be selected 

 which is simple, with accessible parts, and one which will pro- 

 duce a good pressure and a fine even mist of spray. 



ACKNOWLEDGMENT 



I am deeply indebted to Professor C. F. Baker for access to 

 recent new publications of his collections, for checking up various 



