Ill 



down the branches and into the main stem, causing the tops of trees 

 to die back. All dead wood must be cut out and the wounds tarred. 

 Saissetia Jiemisphaerica and a bag-worm, probably Psyche albipes, are 

 also reported. 



Miscellaneous pests include : Leptocorisa acuta (rice bug) ; Orgyia 

 postica (tussock moth) on dadap ; Terias silhetana on Albizzia ; a 

 Hesperid, Parnara sp., on coconuts ; Melolonthid beetles on roses ; 

 and cutworms, Agrotis ypsilon. 



DuPORT (L.). Rapport h Monsieur le President de la Chambre d'Agri- 

 culture du Tonkin et du Nord-Annam sur quelques nouvelles 

 Observations effectuees a la Station Entomologique de Cho-Ganh. — 



Supplement to Bull. 122, Chambre d' Agric. Tonkin & Nonl-Annam, 

 no. 4, April-I\Iay 1919, 10 pp. [Received 5th January 1920.] 



From investigations on the coffee borer [Xylofrechus quadripes, 

 Chevr.] that have been continued since the publication of the last 

 report [R.A.E., vii, 2G9] it is evident that the life-history of the beetle 

 varies considerably according to circumstances, so much so, in fact, 

 as to render research very difficult. It has been proved that repellent 

 washes on the trunks and the treatment of diseased bushes are futile 

 and that more knowledge must be acquired as to the habits of the 

 borer before remedial measures can be successful. Investigations 

 and cage experiments have revealed several new food-plants, some 

 of which are chosen by the borer for oviposition in preference to 

 coffee. Among these is Oroxylon indicum, the fruit of which is edible 

 and the wood useful for making sabots. This tree is common and, 

 although both wood and bark are very different from coffee, it is 

 frequently preferred to the latter for oviposition ; it does not appear 

 however to be well adapted to the development of the insect as the 

 larvae obtained from it were as a rule rather small. Examples were 

 reared on this plant in 5| months after the date of oviposition. Eggs 

 deposited upon Canarium sp., of wliich the bark is almost smooth, 

 on 20th December, produced insects from 21st to 30th May. From 

 two stems of Randia dumetorum with smooth bark and many spines, 

 chosen for oviposition, adults have emerged after five months. An 

 adult has also emerged from Rhus sp. Several other native food- 

 plants are mentioned, and others will doubtless be found. Oviposition 

 on dry bamboo seems to be accidental, any larvae that hatched dying 

 almost immediately. From bamboo stems riddled by galleries 

 resembhng those of X. quadripes only Chlorophorus annularis, Fairm. 

 (bamboo borer) was bred, the adults emerging ten months after the 

 stems were placed in the cages. The hfe-cycle of this borer is therefore 

 considerably longer than that of X. quadripes. 



The factors that influence the females of X. quadripes in oviposition 

 are complex and not yet understood, for the insects do not show 

 consistent habits, even on coffee. The Hfe-cycle obviously Varies, 

 not only with the season of oviposition but also with the individual, 

 the plant on which it is living and the particular conditions under 

 which the larval and nymphal stages are passed. On the cut branches 

 of plants other than coffee the life-cycle has been found to vary from 

 4 to 6 months ; on coffee the variation is from 4 to 8 months at least. 

 Further attempts to infest coffee with the bamboo borer, Chlorophorus 

 annularis, have given negative results. 



