178 



that irrespective of the number of irrigations, infestation was too 

 sUght to affect the yield, but the general climatic conditions were 

 probably unfavourable to the development of this Aphid. 



Hunter (W. D.). The Fight Against the Pink Bollworm in the United 

 States.— i7.S. Dept. Agric. Yearbook 1919, Washington, D.C., 

 1920, pp. 355—368, 4 figs. [Received 10th February 1921.] 

 The work and quarantine regulations in connection with the 

 infestation of pink bollworm [Platyedra gossypiella] in Texas are 

 reviewed [R.A.E..K vi, 543; viii, 13, 244, etc.]. The work is to 

 be continued along the original lines, and a period of not less than 

 two years is recommended for the maintenance of non-cotton 

 zones. The remedial measures must be applied to over 22,000 

 square miles of territory in the United States, if this pest is to be 

 stamped out. The general situation is rather encouraging, and it 

 is possible that the methods employed will prevent the permanent 

 establishment of P. gossypiella in the country. 



Havilaxd (M. D.). Preliminary Note on a Cynipid Hyperparasite 



of Aphides. — Proc. Camb. Phil. Soc, Cambridge, xx, no. 2, 1920, 



pp. 235-238. 



The Cynipid hyperparasites studied during these observations 



belong to the genus Charips {Allotria) ; and Macrosiplium urticae, Kalt., 



parasitised by Aphidius ervi. Hal., was the Aphid used for breeding 



purposes. Although until about twelve hours before death there is 



apparently no external sign that the Aphid is parasitised, yet Charips 



sp. only oviposits in Aphids containing Aphidius sp. and unerringly 



rejects unparasitised incHviduals. Larvae of Aphidius in the third 



or early in the fourth instar are generally chosen for oviposition, 



though eggs may be laid in those of the second instar. In captivity 



oviposition was occasionally parthenogenetic. The eggs hatch in 



about three days. Three or four larvae may be found in the same 



host, but presumably only one reaches maturity. The duration of 



the first-stage larva varies from two to four days. During the fourth 



stage the larva is almost fully fed, and makes its way out through 



the host's thorax ; during the next twelve hours it devours the remains 



of the host. Metamorphosis occurs within the cocoon already woven 



by the Aphidius inside the Aphid. Pupation lasts from three to 



four weeks, and the total period of development probabl}' from 30 



to 35 daj's. The adults after emerging feed on the honey-dew secreted 



by the Aphids. Although these hyperparasites check the destruction 



of the Aphids by Aphidius, they are not considered of great economic 



importance. The Cynipid and its Braconid host are also liable to. 



attack by Chalcid and Proctotrupid hyperparasites, especially in the 



later broods. 



Havilaxd (M. D.). On the Bionomics and Development of Lygoccrus 

 testaceimanus, Kieffer, and Lygocerus cauieroni, Kieffer (Procto- 

 trypoidea— ^Ceraphronidae), Parasites of Aphidius (Braconidae). — 



Qlrly J I. Microscop. Sci., London, Ixv, no. 1, December 1920, 

 pp. .101-127, 18 figs. . 



The various stages of Lygocerus testaceimanus and L. cameroni 

 are described. The bionomics of these hyperparasites of Aphidius 

 have already been noticed [R.A.E., A, viii, 146]. 



