297 



Froggatt (W. W.). Ladybird Beetles and Potatoes. — Agric. Gaz. 

 N.S.W., Sydney, xxxii, pt. 3, March 1921, p. 196. 



Epilachna vigintioctopiinctata is said to be one of the most useful 

 Aphid-destroying Coccinelhds in Austraha, but it also feeds not infre- 

 quently on potatoes and causes serious damage when numerous. 



Leefmans (S.). De Palmsnuitkever {Rhynchophorus ferrugineus, 

 Oliv.). [The Palm Weevil, R. ferrugineus.] — Meded. Inst. 

 Plantenziekten, Buitenzorg, no. 43, 1920, 90 pp., 11 plates, 1 map. 

 (With an Enghsh Summ.ary.) [Received 12th April 1921.] 



These are the first original investigations published in the Dutch 

 East Indies on the coconut palm weevil, Rhynchophorus ferrugineus, 

 Oliv. The work was conducted concurrently v/ith that on the 

 rhinoceros beetle, Oryctes rhinoceros, L., first at Buitenzorg, Java, 

 and then at Padang, Sumatra. [R. A.E., A, ix, 45]. 



In Java the typical R. ferrugineus (red palm weevil) of British 

 India occurs, but in addition there is a black variety with a longi- 

 tudinal red or orange mark on the pronotum, known as R. ferrugineus 

 var. schach, Oliv. ; this is unknown in British India. In Sumatra and 

 Borneo both this and other varieties occur. In the Batjan Islands, 

 West and South New Guinea and Celebes R. papiianus, Kirsch, is 

 found and is evidently the representative in the Austrahan region. In 

 Celebes R. ferrugineus and R. ferrugineus var. schach occur in addition. 

 It may be noted that both these are found in the Philippines, though 

 there the variety is called R. pascha, Boh. Crossing experiments 

 between the Javanese {R. ferrugineus type) and Sumatran [R. ferrti- 

 gineus var. schach) forms showed that the former is heterozygous and 

 the latter homozygous. A curious result of this crossing was the 

 appearance of grubs with visible rudimentar}^ legs and chitinous 

 processes on the mesothorax and metathorax. 



To test the accepted theory that the coconut weevil makes use of the 

 holes made by the rhinoceros beetle, many dying palms were felled 

 and examined. In 17 cases traces of Oryctes rhinoceros only were 

 present ; in 8 cases (6 of which were young palms) traces of 

 Rhynchophorus only ; in 48 cases traces of both pests ; and in 4 cases 

 traces of neither. It is thus possible for coconut palms to be killed by 

 either, but as a rule both are concerned, and therefore the measures 

 taken against Oryctes are useful against Rhyme hop horns. The fact 

 that coconuts, especially between 4 and 10 years in age, can be destroyed 

 by the latter quite independently of the former is important, and it 

 may be said that the injury due to the weevil is the more serious. 

 As Rhynchophorus also attacks ornamental palms {Livistona, etc.) 

 and species of economic value (sago, etc.) its importance as a pest is 

 evident. The larva alone is injurious. In old coconuts the crown 

 is infested, sometimes in conjunction with Oryctes. In 3'oung palms 

 the crown, the trunk, and the root-collar may be affected. Infestation 

 of the crown in both old and young palms is characterised by the 

 dropping of the young heart leaves ; it is nearly always fatal. Felling 

 reveals the internal injury to the trunk, which nmst be destroyed 

 together with the pests it harbours. The trunk infestation and the 

 root-collar infestation found in young palms are revealed b^' the 

 wounds in the trunk from which debris is extruded or by a small 

 hole from which a brown fluid flows. If these signs are noticed early 

 enough it is possible to cure the trouble by removing the larva or 

 killing it in situ. 



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