1 80 



To this figure has yet to be added the number of the grubs and 

 beetles collected on the European Plantations. On the estate of the 

 Deutsche Handels- und Plantagen- Gesellschaft der Sudsee-Inseln zu 

 Hamburg over the same period were collected and destroyed about 

 350,000 grubs and 23,200 beetles. Further the number of insects 

 trapped by the Commission over the same period was 180,000 eggs, 

 776,000 grubs, 220 pupee and 11,300 beetles. The traps will be des- 

 cribed next. 



For the making of a trap a hole is dug in the ground from nine 

 to twelve feet square, and about two and a half feet deep. Rotten 

 coconut stumps, plantain stems, and soil are put into it ; and over 

 the top large leaves such as coconut leaves, breadfruit leaves, and 

 plantain leaves are placed rising perhaps a foot above the surface of 

 the soil. Into these pits the female beetles penetrate to lay eggs and 

 the male beetles to find the females. What beyond digging the traps 

 is necessary is that they should be opened at regular and a not too 

 distant periods, or that the beetles in them may be in some way 

 killed. 



At distances of about one hundred yards along some of the roads 

 in Samoa these traps have made in series, and on the plantation" 

 of the Deutsche Handels- und Plantagen- Gesellschaft there is one 

 trap to every hundred standing trees. 



On the latter estate the traps are opened every six weeks or two 

 months. 



Jepson states that it takes six men about two and a half hours to 

 open and remake one trap; therefore six men can attend to four 

 traps only per diem, or in rotation 160 to 200. He suggested that the 

 traps might b^ treated with bi-sulphide of carbon and not unpacked 

 at all. Six ounces of carbon bi-sulphide were accordingly injected 

 into a full sized trap, which after an interval of twenty-four hours 

 was opened. Then all the larvae in the trap— 450 in number — were 

 found dead ; three mature beetles were partially asphyxiated, but 

 recovered ; rats and mice were found dead. The trap was 

 remade, and re-examined eighteen days later, when to that 

 officer's satisfaction it was found to be again full of beetles, 

 showing that the treatment did not destroy its usefullness, but rather 

 increased it, as a record catch was made. A second trap treated with 

 nine ounces of carbon bi-sulphide at the same time, but opened thirty 

 six hours later, contained 249 dead grubs and one dead beetle. 



Unfortunately the German officers discovered that the cost of 

 carbon bi-sulphide in Samoa is too high to make the method v^rorth 

 adopting. The building of traps, however, is a useful proceeding so 

 long as the organisation for inspecting them is efficient ; for as we 

 saw above by their means in 1912 the Commission collected i8o,000 

 eggs, 776,000 grubs, 220 pupae and 11,300 beetles. 



