Preface. v 



Magazine ; of the late Dr. Riley, Dr. L. O. Howard, and Professor 

 Cockerel!, in the various American journals ; of Professor W. W- 

 Froggatt in New South Wales ; and Herr Karl Sulc, in Bohemia, 

 must all be consulted, together with the writings of many other 

 authors who have dealt with this subject. 



The literature relating to the Coccidce is, unfortunately, very 

 scattered, which adds very considerably to the labour of research. 

 I do not propose to give a complete bibliography of the subject, 

 as a list* of the principal works has already been carefully com- 

 piled by Mr. W. M. Maskell, of Wellington, New Zealand, who 

 has added so much to our knowledge of this group of insects 

 by his long-continued researches on the Coccidae of Australasia. 

 I must, however, specially draw attention to the most admirable 

 and exhaustive papers on Italian Coccidae, by Professor Antonio 

 Berlese,t whose exquisite figures and careful work will prove of 

 great value to the morphologist and physiologist. Professor 

 Cockerell's recently compiled 'Check List' J is a very handy and 

 useful catalogue of all the known species of Coccidae. 



My thanks are particularly due to Mr, Maskell for his un- 

 remitting kindness and assistance in determining specimens ; to 

 Professors Comstock, Howard, and Cockerell, in America ; to 

 Messrs. J. W. Douglas and Robert Newstead, in England ; to Herr 

 Sulc, in Bohemia ; to Dr. W. W. Froggatt, in New South Wales; 

 and to Mr. C. B. Lounsbury, now acting as Government Ento- 

 mologist in Cape Colony ; from all of whom I have received 

 valuable papers and numerous typical specimens for comparison 

 and study. 



Dr. L. O. Howard has kindly named for me various hymen- 

 opterous parasites that prey upon Coccids in Ceylon. 



* Transactions of the New Zealand Institute, 1 891, p. 7. 



t Le Cocciniglie Italiane viventi sugli Agrumi, by Dr. Antonio Berlese. 

 Parts I. (1893), II. (1894), and III. (1896). 



X * Check List of the Coccidae,' by T. D. A. Cockerell. Bulletin of the 

 Illinois State Laboratory of National History, Vol. IV. pp. 318—339, 1896. 



