INSECT PESTS OF DATES IN MESOPOTAMIA. 



291 



became spherical, and inside them the larva could always be found eating the flesh 

 of the date along the stone ; early in July the larva left the dates, which were 

 by now quite dry and about half the size of a healthy date, making its egress by 

 a hole bored close to the attachment of the perianth. From the hole one could 

 always see frass and silk projecting. It is extremely rare to see two emergence 

 holes from one date, and I believe that the eggs must be laid singly, probably on the 

 fruit soon after it is set, and that the larva burrows into it and remains in a single 

 date throughout its period of growth. All my efiorts to find the place of pupation 



y 



• 



• 





Q 3 



P; 



• 



a ./3 



K O 



• 

 • 



o 







K •• 

 r • 



•,vTr 





a 



Fig. 1. Structural details of larva (Fam. Gelechiidae) causing damage to half -ripe 

 dates in Mesopotamia. A. Chaetotaxy of pro and meso-thorax (I, II) and 3rd, 7th 

 and 8th abdominal segments (3, 7, 8). The shield of the prothorax is drawn rather 

 too wide and too deep. The head of the larva is supposed to be towards the left. 

 C. Left proleg of 7th abdominal segment seen from below ; the seta a- is in the 

 direction of the mid- ventral line. D. Anal proleg seen from above. 



Small Greek letters (a, ^, r, w, etc.) indicate individual setae, according to 

 Fracker's terminology. Greek capitals (B, K, etc.) indicate groups of setae, of 

 regular occurrence in certain families or many families of the Lepidoptera, e.g., 

 B = a+i8, P (capital rho) = e+p, T = T4-a;4-0 (?), K = 77+/f. Cr., crochets of proleg; 

 leg, proleg, or leg ; sp., spiracle ; sh, dorsal shield of prothorax. 



were unsuccessful. I searched cracks on the palm stem, the fibrous leaf-sheaths 

 and the rubbish which accumulates in the crown of the tree ; I also passed earth 

 from beneath the trees through a sieve, without finding any pupae except those 

 of large Noctuidae. I believe that pupation takes place in the ground, and lasts 

 throughout the winter, because we always observed that the incidence of the pest 

 was slight in gardens in which a crop of winter and spring vegetables was cultivated 

 beneath the trees. I opened a very large number of the dates which had fallen 

 prematurely as a result of the attack of these larvae, and found no dead larvae, 

 so it appears that the pest is not controlled by parasitic Hymenoptera or 

 entomophthorous fungi. 



