Ixxiv INTRODUCTION. 



As somewhat bearing on this subject Mr. Charles 

 Darwin a:-ks, in one of his letters to Dr. A. Weismann, 

 " Would it. not be worth while to examine the repro- 

 ductive organs of those individuals of wingless 

 Hemiptera which occasionally have wings, as is the 

 case of the bed-bug? " . . . . " The females of ]\hitilla 

 sometimes have wings. These cases [he argues] must 

 be due to reversion." 



Benefits and Injuries done by the Tettigid/E. 



In this utilitarian age it may be expected that 

 something should be said as to the benefits and injuries 

 done to man by the Tettigidae. Whilst a lively interest 

 is evoked in the farmer by the appearance in his wheat 

 crops of the Hessian fly (Cecidonijiia destructor), or in 

 the apple-cultivator by the unwelcome prevalence in 

 his orchards of the codlin moth (Carpocapsa pomonana), 

 the Cicada and its allies are disregarded by the many, 

 because they seem but little to interfere with our own 

 economy : yet in this respect the Family cannot wholly 

 claim the verdict of being "sans peur et sans reproche." 

 The extensive injury done by Cicada scptendccem. in 

 America is notorious. Again, Dclphax saccharivora, or 

 the sugar-cane fly, is very injurious to the plantations 

 of the West Indies. 



Three species of Idioceri have been brought to 

 notice quite recently by Mr. W. Gollan, of the Bo- 

 tanical Gardens at Satiarampur, Calcutta, in British 

 India. These Cicadas subsist on the juices of the 

 young shoots and flowers of the mango. They persist 

 throughout the summer, but the greatest injury appears 

 to be done through damaging the reproductive organs 

 of the plant whilst in flower, and thus preventing the 

 setting of the fruit. These Cicads are described as 

 occurring in some years by myriads. At the request of 

 Dr. E. T. Atkinson these insects have been recently 

 examined and named by M. Lethierry — Idioccrus 



