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GuNN (D.). I. Some Destructive Fruit and Flower Beetles. II. A New 

 Insect Pest of the Pea,ch.— Union of S. Africa. Dept. Agric, 

 Pretoria, Div. Entom. Bull. no. 8, 1916 8 pp. 2 figs. [Received 

 19th July 1916.] 



Section I. of this Bulletin deals with the Cetoniids, that injure 

 cultivated flowers and fruit in many parts of South Africa during the 

 summer. Peaches suffer most from their attack, from 20 to 50 per 

 cent, of the peach crop near Pretoria being damaged. The beetles 

 first appear on early varieties of peaches towards the end of November, 

 and are present in large numbers until the middle of February, when 

 their numbers gradually begin to decrease. Other food-plants 

 include pears, plums, nectarines, apricots, figs, grape-vine fohage, 

 orange-blossoms and Acacia horrida (wild thorn). The dift'erent species 

 of Acacia are apparently the native food-plants. The following species 

 were abundant in Pretoria during the summer of 1913-14 : — Rhabdotis 

 aulica, Pachnoda impressa, P. cincta, P. carmelita, Heterorrhina 

 flavomaculata, Plaesiorrhina recurva var. plana, Oxythyrea margarita 

 and 0. dysenterica. As many as fifteen beetles of different species were 

 frequently seen feeding on a single peach, and over five hundred were 

 counted on one peach tree. The life-history of these beetles is believed 

 to be similar to that of the cockchafers or May-beetles, and from 

 one to two years may be spent in the soil in the larval and pupal stages 

 before the adults emerge in the early part of the summer. Only a few 

 beetles were caught in the course of tests with odorous oils, such as 

 paraffin, eucalyptus and oil of citronella. From an experiment made 

 with the object of discovering whether the beetles hibernate in the 

 winter, it seems probable that the females deposit their eggs at the end 

 of the season and then die. As the beetles invariably attack ripe or 

 nearly ripe fruit, an arsenical spray, if used sufficiently strong to destroy 

 them, would be dangerous. Collection is a practical remedy, but as 

 the beetles are easily disturbed, precautionary measures have to be 

 adopted, as their flight is very swift. A butterfly net made of stout 

 wire and cheesecloth, of 18 inches in diameter, mounted on a 5-foot 

 pole, was found to be the best for this purpose. This is placed under 

 the branches and the beetles, when disturbed, drop into it. As many 

 as 150 were caught at one time in this manner. Cloths placed under 

 the tree and butterfly nets of larger diameter (three feet) did not give 

 such good results. The captured beetles should be killed by dropping 

 them into a tin containing 1 part of paraffin to 8 of water. By adopting 

 this method in the summer months from mid-November to mid- 

 February, all injury to fruit can be prevented. 



Section II. deals briefly with the Longicorn, Philagathes laefus, a 

 new insect enemy of the peach, which it damages in conjunction 

 with the Cetoniids. It was first seen in mid-December and continued 

 to injure early varieties until mid-January. Only ripening or ripened 

 fruits suffer. This pest is likely to escape notice, as it has the habit of 

 burrowing into the fruit until only the end of the abdomen is visible. 

 It is sluggish when feeding and not so easily disturbed as the Cetoniid 

 beetles. It has also been recorded from Buluwayo, Rhodesia. As 

 nothing is known of its fife-history, no remedy can be suggested 

 against the early stages. The adults can be easily caught and 

 destroyed in the same manner as the Cetoniid beetles. 



