1916 ENTOMOLOGICAL SOCIETY. 23 



apparently got good results, because wlieu 1 visited his place later on I found com- 

 paratively few beetles on the bushes. 



The Easpberry Sawfly (Monophadnoides ruhi). This pest was very 

 troublesome last year, but I regret to say it was much more destructive this season. 

 Two large raspbexry plantations near Vineland were very badly infested and on 

 many of the bushes all that was left of the foliage was the petioles and leaf ribs. 



The raspberry sawfly is readily controlled by spraying with; arsenate of lead, 

 but as the insect is not regularly injurious the fruit grower seldom thinks of 

 applying the remedy until it is too late. 



The Privet Plant Louse (Rhopalosiphum ligustri). This greenish-yellow 

 aphid was again very abundant on privet and as a result of its depredations 

 several beautiful hedges were partially defoliated. 



/ Last year I referred to this insect with some doubt as the European species 

 Rhopalosiphum ligustri. However, there is no longer any question in regard to its 

 identity, as my determination was confirmed by Prof. Theobald, of London TJni- 

 versit}', England, who kindly examined some specimens which were sent to him. 



Before coming to this meeting I had occasion to examine, an infested privet 

 hedge, and I was greatly interested to find three kinds of males present, viz. : 

 winged, wingless and forms intermediate between alate and apterous. This would 

 seem to suggest that the male of R. ligustri is in an unstable condition and that it 

 is gradually changing from the primitive to the specialized form, i.e., from alate 

 to apterous. 



The Asparagus Beetle Parasite {Tetrastichus asparagi). Early in June 

 this interesting chalcid, heretofore unrecorded in Canada, was found destroying 

 the eggs of the asparagus beetle {Crioceris asparagi L.) at Vineland Station. 



Tetrastichus has a very curious life history. The female by means of a sharp 

 ovipositor pierces the egg of the asparagus beetle and deposits within it her own 

 eggs (from three to nine in number according to dissections which I made). In 

 due course, the beetle egg, its viability unaffected, hatches, and Ihe grub grows to 

 maturity. The chalcid eggs in the meantime hatch and the parasites apparently 

 nourish themselves on the body fluids of their host without appreciably interfering 

 with its development. The full-grown asparagus grub enters the soil and forms 

 the pupal cell, but proceeds no further because at this stage it is wholly consumed 

 by the chalcid larvse. The parasites then pupate within their host's cell and later 

 emerge as adults. 



The adult Tetrastichus is a voracious feeder on the eggs of the asparagus 

 beetle and in this capacity the insect is really of greater economic importance than 

 in the role of a parasite. In support of this statement I may mention that early 

 in June asparagus beetles and their eggs were exceedingly abundant on the 

 asparagus plants at the Vineland Experimental Farm, but the hungry chalcids 

 destroyed so many eggs that very few grubs hatched out — less than one per cent., 

 I should say. Later on when the parasites were not so plentiful a larger per- 

 centage of the beetle eggs hatched. 



In feeding the chalcid stands on the egg, plunges her ovipositor into it, and 

 energetically works the ovipositor up and down usually for three or four minutes. 

 She then steps back, applies her mouth parts to the puncture and feeds on the egg 

 contents. If the first prodding does not render sufficient food available the oper- 

 ation may be repeated. In fact I noticed one chalcid attack an egg no less than 

 four times. 



