128 PROCEEDINGS ENTOMOLOGICAL SOCIETY 



c. tarsi broadly cordiform. 



d. prothorax with smooth bare spots on either side of disc before 



middle, elytra marmorately pilose cacicus 



dd. prothorax without smooth bare spots on the disc, vestiture of 



elytra not marmorate sphenosomus 



cc. tarsi with joints feebly broadened, not cordiform edmonstoni 



Oistus Candeze, Monogr. Elat. I, p. 338, 1857. 



1. Oistus cacicus Cand. 1857 Monogr. Elat, I, p. 339, PI. VI, 



fig. 5 (type of the genus by present designation). Champion 

 1894, Biol. Cent, Amer. Col. Ill, pt. 1, p. 292, PI. XIII, fig. 8. 



Ludius cacicus Dej. 1833 Cat. ed. 3, p. 107, Cand., I.e. 



Oistus griseosignatus (Dupont i. litt, ) Gem. and Har. Cat. 

 Col. V, p. 1506. 



2. Oistus sphenosomus Cand. 1857 Monogr. Elat. I, p. 339. Cham- 



pion 1894, I.e., p. 292, PI. XIII, fig. 7. 



3. Oistus suturalis Champion. 1894 I.e. p. 553, PI. XXIV, fig. 5. 



Schwarz 1906 Gen. Ins. 46, PI. II, fig. 13. 



4. Oistus submetallicus Dand. 1900 Ann. Soc. Ent. Belg., Vol. 44, 



p. 83. 



5. Oistus edmonstoni Hyslop 1917 above. 



NOTES ON THE BIOLOGY OF SCHIZONOTUS SIEBOLDII RATZ. 1 



BY R. A. CUSHMAN, 

 Entomological Assistant, Bureau of Entomology. 



Very few cases are on record of chalcids feeding as external 

 parasites on hosts unprotected by the tissue of their food plant 

 or food substance or by their cocoons or other protection of the 

 pupa. A notable example of this is found in the eulophid genus 

 Euplectrus, the life-history of one species of which, E. comstoelci-i 

 Howard, is well known in its relation to the cotton worm. We 

 are now able to add another species to the cha*lcids having this 

 habit, Schizonotus sieboldi Ratz., a species introduced from 

 Europe. In connection with his original description of this 

 species (Ichn. d. Forstins., Ill, 1852, p. 230), Ratzeburg stated 

 that it was reared by von Siebold from Chrysomela populi, and 

 from the date of emergence judged that it must have been reared 

 from full-grown larvae or pupae of the host, 



1 Published by permission of the Secretary of Agriculture. 



