HYMENOPTEROUS PARASITES OF COCCID.E. 27 



expected but natural phenomena in insect-life. Or else why is 

 one comparatively so little stirred by the marvels of sexual 

 dimorphism if it is not because he is accustomed to these pheno- 

 mena, almost from the very moment that be acquired conscious 

 sight in earliest childhood by the familiar examples in picture- 

 books, pets, and the useful domestic animals ? I remember 

 — before I ever had looked into a butterfly book— showing as a 

 " new different " species my first examples of the real " butter- 

 coloured " fly, pinned in a separate box, and then being only 

 mildly astonished and rather ashamed at my ignorance and 

 want of penetration when it was pointed out to me that my 

 beautiful "yellows" were identical as a species with certain 

 greyish-greenish butterflies which I had placed among the 

 "common whites" because of their colour! This my first 

 experience of extreme sexual dimorphism in entomology did not 

 shake me up like my later meeting with levana and prorsa ; it 

 seemed quite " matter of course" ! 



(To be continued.) 



ON THE HYMENOPTEEOUS PARASITES OF COCGID.E. 

 By Claude Morley, F.Z.S., F.E.S. 



(Continued from vol. xlii. p. 278.) 



43. Pulvinaria. 

 From a species of this genus upon Oregon flowering currant 

 Ashmead (p. 387) records Aphycm oregonensis, How., and from 

 another, from Iowa, his A. pulvinaria (p. 388). 



44. Pulvinaria I'itis, Linn. 

 This well-known pest is destroyed by a variety of parasites in 

 Europe and America. First, Curtis records (Brit. Ent. pi. et 

 fol. 395) : " For specimens of this insect [his Encijrtus vitis] 1 

 am indebted to Mr. Samouelle, who bred them from the Coccus 

 of the vine. Found on the vine in Lambeth, July 9th and 10th, 

 1830." Next, Goureau (Ann. Soc. France, 1863, Bull. p. iv. ; 

 quoted by Gaulle, 109) bred Eulophus scutellaris, Nees. And in 

 1875, Dr. Mayr gives Encyrtus duplicatus, Nees; Blastothrix 

 schonherri, Westw. ;t Aphycus puncticeps, Dalm., which also 



f Quite the most circumstantial account of parasitism upon Coccids I 

 have seen is given by Newstead, vi^bo says (Mon. Brit. Coccids, ii. 66) : — 

 " Wlien the colony of Pulvinaria vitis var. ribesice under observation was 

 first established, the insects were quite free from internal parasites. But the 

 second generation became infested by chalcidid parasites, which increased in 

 the third generation to such an enormous extent that quite fifty per cent, of 

 the coccids were destroyed by them. The few coccids which now remain are 



apparently all parasitized On the 17th of October, 1901, after long and 



careful watching, I observed one of the chalcidid parasites in the act of laying 

 its eggs in the body of a coccid. When first seen the parasite was running 



