June, '17] FERRIS: STUDY OF MEALY-BUGS ^ 321 



(5) Severin, H. H. p. and Hartuxg, W. J., 1912. Will the Mediterranean Fruit- 



fly (Ceratiiis capiiata Wied.) Breed in Bananas under Artificial and Field Con- 

 ditions! Jour. Econ. Ent. V, No. 6, pp. 443-451. 



(6) Severin, H. H. P., 1913. Precautions Taken and the Danger of Introducing 



the Mediterranean Fruit-fly {Ceratitis capitata Wied.) into the United States. 

 Jour. Econ. Ent. VI, No. 1, pp. 68-73. 



Chairman A. W. INIorrill: As we shall probably have plenty of 

 time we might as well discuss the papers as we go along. Discussions 

 are now in order. 



Mr. Dudley Moulton, Prof. R. W. Doane, E. O. Essig and Dr. 

 Severin took part in the discussion which followed. 



Chairman A. W. Morrill: The next paper will be read by Mr. 

 G. F. Ferris. 



METHODS FOR THE STUDY OF MEALY-BUGS 



By G. F. Ferris, Stanford University, California 



The economic importance, both actual and potential, of certain of 

 the mealy-bugs renders the problem of recognizing the various species 

 one of more than merely academic interest. It is the problem of dis- 

 criminating between foe and foe or foe and neutral and thus it is of 

 direct interest and of directly perceptible importance to the economic 

 entomologist especially in California where certain species of mealy- 

 bugs are among the worst of pests. 



However, it is no exaggeration to say that of the nearly 100 species 

 of mealy-bugs and their allies thus far described from North America, 

 including some 35 from Cahfornia, not more than three or four are^ 

 recognizable at all on the basis of the existing literature if taken apart 

 from their typical host and their type locality. Furthermore these 

 three or four are not at all times and under all circumstances recog- 

 nizable with certainty, even upon the basis of the direct comparison 

 of specimens, by means of the methods and the characters at present 

 in use. 



In support of this latter statement I may adduce as evidence the 

 fact that I have at hand at the present time a slide mount of a Pseu- 

 dococcus determined by one who is perhaps as familiar with the 

 mealy-bugs of this state as anyone and labeled '' Pseudococcus citri." 

 The slide contains four specimens and of these three are Pseudoc'occus 

 longispinus and one is Pseudococcus ohscurus, or as it is better known, 

 Pseudococcus bakeri. This is a confusion of three of the most widely 

 spread and most familiar species of the state. Nor is this by any 



