330 Phylum Arthropoda 



an egg was placed on a catalpa leaf which was then inserted in a vial 

 and tightly corked. At intervals of two or three days each individual 

 was transferred by means of a camel's hair brush to a fresh leaf and the 

 old leaf removed from the vial. When the females reached maturity an 

 adult male which was still in its cocoon was placed in each vial. The 

 eggs were removed daily from each vial during the period of oviposition. 



The potted catalpa seedlings were used to a limited extent in the second 

 method. A narrow paper band was placed on the trunk of each seedling 

 and each band was kept covered with a fresh coating of tanglefoot to 

 prevent migration on or off the tree. Above the tanglefoot band on the 

 main trunk or on one of the laterals a band of burlap was loosely tied 

 in order to afford a convenient place in which the males could cocoon. 

 Sometimes the females also preferred to crawl beneath the burlap band 

 just before beginning oviposition. When one individual shifted its posi- 

 tion between molts so that it could no longer be distinguished from an- 

 other specimen, both specimens were considered lost from the records 

 for that stage of their development. No difficulty was encountered in 

 rearing the mealybugs on the potted seedlings, but the fact that the in- 

 dividuals shift about from place to place makes observations very difficult 

 to obtain if a consecutive record from molt to molt is desired for each 

 specimen. Usually two to ten mealybugs were kept on each seedling and 

 as far as possible not more than one individual was allowed to remain for 

 any length of time on a leaf. The occurrence of a molt was indicated by 

 the cast skin beside the insect. For a continuous record of the same in- 

 dividual from egg to adult it was necessary to employ the vial method of 

 rearing rather than rearing a few individuals on each potted seedling. 



It was learned that burlap bands placed on limbs of Catalpa bungei as 

 well as on potted seedlings of catalpa offered favorable feeding places for 

 mealybugs in all stages of development. A gall-like growth usually de- 

 veloped beneath each band after the insects had been feeding for a short 

 time. 



Reference 



For a convenient caging method for the Coccidae see p. 320. 



