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A LIST OF THE MORE IMPORTANT INSECT PESTS OF 

 CROPS IN THE NYASALAND PROTECTORATE. 



By E. Ballard, 

 Government Entomologist^ Nyasaland Protectorate. 



The following paper gives a list of those insects of economic importance which 

 have been collected or bred from various crops in Nyasaland during the first 

 three months of the planting season 1911-12 and the whole of the season 1912-13. 

 No attempt has been made to describe the various species mentioned, but their 

 actual economic importance is stated in each case, so far as it has been possible 

 to ascertain it during so short a period. All insects have been included as pests 

 which have been found to feed en any particular crop in sufficient numbers to 

 justify their inclusion in that category. In many cases the actual damage done 

 may be slight, but at any time one or all of those species which feed regularly on 

 crops may assume the position of dangerous pests, and so insects of apparently 

 minor importance are included with those of definite and proved powers of 

 destruction. The insects of first-class importance, which annually inflict heavy 

 losses on the planters, are ten in number. These ten are confined to cotton, 

 tobacco and maize, of which cotton is the worst sufferer, since it is attacked by 

 a greater variety of insects than any other crop that has come under the writer's 

 notice. Except where the contrary is specially mentioned, insects included in 

 this paper are from the Shire Highlands. 



Orthoptera. 

 Acridiidae. 



There are two insects of this family which are really troublesome. In both 

 cases they eat the leaves of young tobacco plants in the nurseries. The injury 

 done is not really very great at any one time, but the aggregate damage during 

 the season is fairly considerable. These two species are : — Maura bolivari, Kirby, 

 and a species of Chrotogonus. 



The other species are collectively destructive in varying degrees. In the 

 planting season 1911-12 Acridiidae were very troublesome amongst freshly 

 planted tobacco ; in the present season 1912-13 their depredations were hardly 

 noticeable. Acrida turrita, L., was an exception to the above statement, as it 

 was committing a fair amount of havoc on an experimental plot of Turkish tobacco, 

 in the Lower Shire District. The brightly coloured Zonocerus elegans, Thunb., 

 also occasionally becomes a minor pest. 



The remaining species, so far as at present known, are : — Catantops opu- 

 lent us, Karsch, C. solitarius, Karsch, C. vittipes, Sauss., C, melanostictus, 

 Schaum, Morphacris fascia.tus, Thunb., Oedalens, citrinus, Sauss., Gastrimargus 

 marmoratuS) Thunb., G. wahlbergi, Stal, Acrotylus patruelis, U.S., Oxyrrhepes 

 procera.) Burm., and AerWium Uneatum, Stal. 



