98 G. H. CORBETT. 



Food Plants. 



This thrips seems to feed on most plants, cultivated or wild, and below is a list 

 of the plants on which the larvae have been observed. In course of time, no doubt, 

 other plants will be found to sustain this insect, and attention may be called to the 

 wide range of botanical orders represented in the Hst. Mr. R. E. Massey, 

 Government Botanist, kindly identified most of the wild plants. 



Cultivated Plants. 



Potatoes, field beans, French beans, butter beans, ground-nuts, wheat, barley, 

 peas, turnips, cabbages, cowpeas, bamia, beetroot, sweet potato, lettuce, carrot, 

 clover and cotton, both American and Egyptian. 



It has been reported as attacking Lubia (Lubia afin) and Dura, but this the writer 

 has not been able to confirm. 



American cotton suffers very much more than the Egyptian, and whilst Eygptian 

 €otton recovers remarkably after a severe infestation, in the American variety the 

 percentage of recovery is much smaller. 



Wild Plants, 

 Malata, the most common plant in the Gezira, generally found with thrips. 

 Leucas nubica, Benth. (ungalot) ; very common, and always supporting thrips. 

 Phyllanthus niruri, Linn. 

 Tephrosia emeroides, Linn, (surep). 

 Oucumis melo, Linn. 

 Corchorus olitorius Linn, (molokhia). 

 Digera arvensis, Forsk. (heyrayrah). 

 Solarium incanum, L nn. (gibbein). 

 Ipomoea cordofana, Choisy (hantut or tubba). 

 Heliotropium europaeum, Linn. 

 Heliotropium supinum, Linn. 

 Ocimum basilicum^ Jjiim. (rihan). 

 Polygala triflora, Linn. 

 Crotalariasi^. 

 Ahutilon sp. (hambook). 

 Ahutilon sp. (saphirah). 

 Rhyncosia memnonia, Linn, (myoda). 

 The local native names for most of the weeds are given in brackets. 



Life Cycle. 



Observations were made on this insect only from the month of 'November to the 

 beginning of August. It is doubtful if there is any aestivating period, and the WTiter 

 is incHned to think that there is no resting stage though, after the rains commenced 

 considerable search was needed to find specimens of the insect. The differences in 

 the lengths of each stage are remarkable, but under absolute field conditions the 

 life-cycle is a short one, and the thrips quickly reproduce in large numbers. 



