For additional information as to useful Coccidae, see Blanchard, Bull. Soc. Zool. France, viii. 1883, p. 217.
Rubsaamen's paper on these Insects gives references to most of the previous literature, Berlin. ent. Zeitschr. xxxix. 1894, p. 199.
Ent. Meddel. iii. 1891, p. 82.
Cf. Graber, Zeitschr. wiss. Zool. xxii. 1872, p. 165, and Landois in the same Journal, xiv. 1864, p. 24.
Ann. Nat. History (3), xvii. 1866, p. 213.