ECONOMIC ZOOLOGY — ^ENTOMOLOGY. 861 



which is of considerable importance through its clearing oranges and rose trees 

 of aphids in Brazil. 



Life history of Oberea tripunctata, A. G. Ruggles (Jour. Econ. Ent, 

 S {1915), No. 1, pp. 79S5, figs. 6). — The beetle here considered has become a pest 

 in the parlis of St. Paul, Minn. In June, 1911, all the trees along one of the 

 finest avenues of that city were found by the author with numerous dead leaves 

 hanging from the terminal twigs and the ground strewn with loaves. Studies 

 have since been made of its life history and are here reported. 



The eggs are inserted under the edge of the slit bark of twigs, below the 

 completed girdles, many often being found in a single stem, although all be- 

 tween the complete girdling next the main stem and the end of the twig soon 

 perish. Five larval instars have been observed and are here described. Pupce 

 were found only in the second year after the eggs, usually in May. It was 

 estimated that in 1911-12 fi'om 50 to SO per cent of the larvre were parasitized. 

 The cutting out and burning of infested twigs was recommended and appears 

 to have given satisfactory results in the control of this borer. 



On the life history of Aleochara bilineata, a staphylinid parasite of 

 Chortophila brassicae, J. T. Wadswokth (Jour. Econ. Biol., 10 (1915), No. 1-2, 

 pp. 1-27, pis. 2, fig. 1). — An account is here given of the life history of a 

 staphylinid beetle, the larvse of which parasitize the pupns of the cabbage root 

 fly (C. brassicce), including technical descriptions of its stages. 



" It is shown that the larva of this insect hatch from the ova in the form of 

 typical, free-living, campodeiform, staphylinid larvse. They enter the puparia 

 of the cabbage fly, feed on the pupae contained therein, and at the first ecdysis 

 emerge as eruciform larvae. They thus undergo a simple form of hypermeta- 

 morphosis as the result of their parasitic mode of life. Three ecdyses occur 

 during larval life. Previous observers believed that ova or larvse of the beetle 

 enter the fly larvae; this view, however, is shown to be erroneous. After the 

 first ecdysis the larvae feed rapidly ; pupation takes place within the puparium 

 of the host, and the adult beetle, after gnawing a hole in the wall of the 

 puparium, emerges therefrom. 



" Two generations of these staphylinids are produced annually in the Man- 

 chester district, and it is suggested that in warmer climates three or more 

 generations may be produced in a year. Adults of the first generation emerge 

 in May and June ; as larvae they entered the host puparia in late autumn of the 

 previous year. Apparently eight or nine months elapse while the individuals of 

 this generation undergo their metamorphoses. Adults of the second generation 

 emerge from the host puparia in August and September. Six or seven weeks 

 only are occupied by this generation in completing the developmental cycle. 

 The rate of development of larvae obtained in winter may be greatly increased 

 by placing them in warm surroundings. Adults, which would normally emerge 

 in May or June, may be thus obtained in midwinter. It is suggested that other 

 members of the genus Aleochara will be found to have similar life histories, 

 possibly with modifications. It is also probable that the larvae of A. Ulineata 

 parasitize other dipterous hosts than C. hrassicw. 



« Two hundred, and thirty-nine cabbage fly puparia infested by staphylinid 

 larvse were obtained from 2,189 puparia examined, equivalent to 10.9 per cent. 

 The puparia collected during the summer months showed a higher percentage 

 of pari'sites viz 26.9 per cent. It is estimated that at least 20 per cent of the 

 nrv5fi 'and pupjB of C. hrassicce are destroyed by coleopterous and hymen- 

 opterous parasites in the district where the material for this investigation was 



'"^'irview of the marked destructiveness of the cabbage fly and of the fact 

 that practical methods of reducing it in numbers do not appear yet to have 



