261 



exposed, and lizards may kill a few. Predators of the adults have 

 practically no efiect, as the beetles remain hidden during the day. 

 A small mite occurs as an ecto-parasite on the larval, pupal and 

 adult stages, but does not seem to affect development in any way. 



Control measures for 0. rhinoceros are difficult to evolve. Remedies 

 against the adults are impracticable, as the injury is not apparent until 

 too late to save the palm. The nocturnal habit of the beetles makes 

 collection difficult. Poison is ineffective, as the beetle does not feed 

 mitil the heart of the tree is reached. Banding or covering the trunks 

 has not yet proved practical. On the other hand about 80 per cent, 

 of the larvae can be found in refuse heaps and dead coconut logs, so 

 that by gathering and burning these logs all immature beetles therein 

 are killed, while adults are deprived of suitable breeding sites. As 

 available breeding places are reduced, larger numbers of the beetle 

 resort to those that are left and, applying this theory, it is found 

 that compost pits constructed in suitable spots attract large numbers 

 of beetles which oviposit therein. If these traps are cleaned out once 

 every six months all immature stages of the beetle can easily be 

 destroyed. Decayed stumps can be easily impregnated wdth a poison 

 solution by boring holes into them with an augur and filling these 

 holes with the solution. The water then evaporates allowing the 

 poison to remain and killing anything that feeds on the poisoned 

 wood. Fallen logs can be treated in the same way ; 1 lb. sodium 

 arsenate to 40 gals, water will kill 0. rhinoceros in any stage, in from 

 4 to 36 hours. 



In discussing the possibilities of an organised campaign against 

 the beetle, and the necessity for co-operation, the author is strongly 

 of opinion that to attain success the matter must be taken up under 

 government super\'ision and conducted systematically by forces 

 trained and familiar with the work. The loss sustained to coconut 

 planters by trees killed is estimated at nearly £600,000, about 80 per 

 cent, of which is preventable by simple control measures. 



Kingman (F. C). Important Root Crops of the Philippines.— PAz7i;jjome 

 Agric. Rev., Manila, x, no. 4, 4th Quarter, 1917, pp. 335-349, 

 5 plates. 



The most injurious pest of sweet potatoes in the Philippines is 

 Cylas formicarius, F. (sweet potato weevil), which deposits eggs in 

 recesses at the base of the vine or at the upper end of the root. The 

 maggots bore into the roots and when in sufficient numbers completely 

 riddle the potatoes and destroy them. Pupation occurs in the root, 

 whence the adults emerge to infest another crop. If the crop is dug 

 early in the vicinity of Manila no serious damage is done. Control 

 measures consist of early harvest, rotation of crops and the burning 

 of all root refuse. 



LouNSBURY (C. P.). Cenititis cosijra and C. capitata, Diptera Injurious 

 to Fruit Trees in South Africa. — Mthhj. Bull. Agric. Intell. d PL 

 Dis., Rome, viii, no. 5, May 1917, pp. 816-817. [Abstract from 

 Agric. Jl. South Africa, Johannesburg, iv, no. 24, December 1916, 

 pp. 180-181, 1 plate.] [Received 24th April 1918.] 

 The fruit-flies, Ceratitis rosae {cosyra) and C capitata, are responsible 



for nearly all the damage done to cultivated fruit trees in S. Africa, the 



