M. T). Haviland 173 
5. The length of the larval and pupal life of the parasite is intimately 
correlated with the puparial period of the host. 
6. It is suggested that this is an adaptation to ensure that an adequate 
supply of host larvae shall be hatched by the time that the parasites are ready 
to oviposit. 
7. Certain Chalcididae of the genera Eulophus and Chrysocharis are ecto¬ 
parasites of Ph. angelicae, and a summary of observations on their life cycle is 
given. 
REFERENCES. 
Alston, A. M. (1920). The Life-history and habits of two Parasites of Blowflies. Proc. Zool. 
Soc. No. xv. 
Haviland, Maud D. (1921). On the Bionomics and Development of certain Cynipid hyper- 
parasites of Aphides. Quart. Journ. Microsc. Sci. lxv. Part in. 
- (1922). The Bionomics of certain parasitic Hymenoptcra. Proc. Camb. Philos. Soc. 
xxi. 27. 
Henneguy, M. L. F. (1892). A Contribution to the Embryogeny of the Chalcididae. Ann. 
Mag. Nat. Hist. x. 
Keilin, D. (1915). Recherches sur les Larves des Dipteres cyclorraphes. Bull. Sci. Fr. Bclg. 
7ieme s., lxxvii. 
Keilin, D. and Picado, C. (1913). Evolution et formes larvaires de Diacliasma crawfordi. 
Bull. Sci. Fr. Belg. 7ieme s., xlvh. f. 2. 
Marshall, T. A. (1885). A Monograph of British Braconidae. Trans. Ent. Soc. London. 
Pluvinel, G. de la Baume (1914). Evolution et formes larvaires d’un Braconide, Adelura 
gahani, parasite interne d’un Phytomyzine. Arch. Zool. Exper. lv. 
Seurat, G. H. (1899). Contributions a l’Etude des Hymenopteres entomophages. Ann. 
Sci. Nat. 8ieme s., ix. 
Tragardh, I var (1909). Zur Kenntnis von Phytomyza xylostei Kalt. Zeitschr. wiss. Insekten- 
biol. v. 
