22 Injurious and Beneficial Insects. 



the surface of the ground, be placed among the plants to attract 

 the caterpillars when about to change to a chrysalis. 



Mr. Curtis has described and figured several parasites of the 

 three species of cabbage butterflies found in England, and he 

 shows how thoroughly they keep in check these troublesome 

 worms. Certain minute ichneumon flies (Chalcids) lay their 

 eggs in those of the butterflies. Another chalcid fly (^Pteromalus 

 brassicce) lays its eggs on the outside of the chrysalis of the 

 white cabbage butterfly {Pieris brassicce'), and sometimes 200 

 or 800 of the little chalcid maggots have been found living riot- 

 ously within a single chrysalis. They turn into minute brilliant 

 flies, which multiply in excessive quantities. Mr. Curtis remarks 

 that " some species of this extensive genus (Pteromalus), prob- 

 ably comprising nearly 1,000 species (!) swarm even in our 

 houses, especially in the country, where in October and Novem- 

 ber I have seen immense numbers inside of the windows, and I 

 believe that they hybernate behind the shutters, in the curtains, 

 &c." 



The Bean Weevil. — Since the article entitled " New and 

 little known Injurious Insects " was printed in the last report of 

 the Board of Agriculture, I sent specimens of the bean weevil, 

 mentioned under the name of Bruchns g-ranaj-ius, to Dr. G. A. 

 Horn, of Philadelphia, who pronounces it to be not the European 

 B. g-ranarius, but a native species {B. varicornis of Leconte). 

 Mr. S. S. Rathvon, in the " American Entomologist " (Vol. 2, 

 p. 118), states that Dr. Leconte, of Philadelphia, has had 

 specimens of this species " raised from beans and cow-peas." 

 Another common weevil is the Bruchus obsoletus of Say, a 

 smaller species than the one mentioned above. It is blackish 

 ash colored, and differs, according to Dr. Leconte, " in having 

 the feet and the base and last joint of the antennas black, 

 whilst in varicornis they are testaceous (honey-yellow)." 



INSECTS INJURIOUS TO SHADE AND FOREST TREES. 



T/ie Juniper Span Worm. — Many insects, either in the young 

 or adult stages, or both, bear a wonderful resemblance to the 

 plants, or portions of them, on which they feed, or disguise them- 

 selves in various ways to protect themselves from their insect or 

 bird enemies. One of the most wonderful examples I have ever 

 met with is the Juniper Span worm, (Plate 1, Fig. 4, and chry- 



