i8o A VISIT TO THE RUBBER PLANTATIONS 



affected by scale, some of them quite badly, the insect appearing to have 

 practically destroyed the lactiferous tubes, so that the outer bark pre- 

 sented a curious shrunken appearance. This scale, as far as I was able 

 to observe, only appeared where neither undergrowth nor weeds were 

 in evidence round the foot of the tree. All of the trees thus affected were 

 uprooted and burned. I brought samples of the stems back to the 

 United States, however, and through the courtesy of the experts at the 

 Connecticut Agricultural Experiment Station at New Haven, and the 

 Bureau of Entomology at Washington, I was able to identify the dis- 

 ease and also to discover simple remedies. The reports of the two ento- 

 mologists follow : 



DEAR SIR : Your letter with specimens has been referred to me. 

 The tree seems to be attacked by two species of scale insects , the large 

 brown one is a Lecanium, and the small, glassy, greenish yellow one is 

 an Asterolecanium. We do not have the literature by which I can 

 determine them specifically. From a knowledge of simliar species 

 found in this part of the country, I should expect that a thorough spray- 

 ing with kerosene emulsion or whale oil soap would destroy them, though 

 of course experience is needed to know just how strong to make the 

 mixture. I should try some of these made in the proportion recom- 

 mended in published bulletins, and if it did not kill them. I should use 

 somewhat stronger mixtures. 



Very truly yours, 



W. L. BRITTON, 



State Entomologist, The Connecticut Agricultural Ex- 

 perimental Station, New Haven, Connecticut. 



DEAR SIR: The scale insects upon the twigs which you sent repre- 

 sent the akee fringed scale (Asterolecanium pustulans), and Lenaci- 

 odiaspis rugosus (?). This Asterolecanium is very common and very 

 injurious in the West Indies. It works principally upon akee,' oleander, 

 fig, and hibiscus. Mr. Maxwell-Lefroy, the government entomologist 

 to the West Indies, in pamphlet series No. 7 of the Imperial Department 

 of Agriculture for the West Indies, recommends kerosene emulsion for 

 the control of this insect. His formula and method of preparation is 

 as follows: " Kerosene emulsion: Dissolve one-half pound of hard soap 

 in one gallon of water ; add two gallons of kerosene to the hot liquid, 

 and immediately chtirn with a syringe or force pump until the mixture 

 becomes creamy. This is a stock solution. Make up to thirty-three 

 gallons. Use only rain or soft water. " 



