334 POMONA COLLEGE JOURNAL OF ENTOMOLOGY 



is .sometimes found on a tree, but they are strictly solitary, as are all our North 

 American Papilios. P. oxynius Hubner in Cuba, however, is social, the larva- 

 being commonly found gregariously on the food-plant, Xanthoxyhnn (prickh- 

 ash ) . 



It is quite probable that the "California Orange Dog'' will in the future- 

 be of some economic importance to the orange growers of this state. The 

 fact that the citrus industry of Tulare County is but of recent date, shows 

 how suddenly the change from a natural to an adopted food-plant may be 

 elifected. Not a trace of ::elicayn eggs, larvre or pupre were to be found 

 on all the umbells that I observed about Porterville. Furthermore, Mr. R. W. 

 G. Wright of San Bernardino informed in recent conversation that he has 

 had caterpillars of zelicayn from orange sent to him from Riverside. Xn 

 doubt the progress of civilization, destroying and exterminating-, natural tood- 

 plants, has caused zcUcayn to make this change, such as in the case of the 

 notorious Colorado potato beetle. 



A number of larvae in various stages were condemned to parasites. A 

 fachinid fly was present in a few instances, but the majority of the parsites 

 produced were of a species of Apantelcs, which emerges before the larvse has 

 attained maturity and forms a small dirty-yellowish cocoon on the leaf or 

 stem of the plant. 



As to remedies, hand-picking is by far the least expensive and most 

 practical. The shooting of P. cresphontes had often been advocated, but 

 probably affords more entertainment than benefit. Pupation apparently does 

 not occur on the food-plant, so that the cleaning up and burning of all rubbish 

 about the trees should destrov many future individuals. 



