303 



(d) CRITICISM OF PREVIOUS SYSTEMS. 



After this short and very imperfect survey of the external 

 structure and the Hfe history of the leaf-hoppers. I propose lo 

 comment very briefly on the lines of classification laid down by 

 the Masters i'n Hemiptera, cited near the beginning of this pa- 

 I)er. 



Unfortunately, owing to my almost entire lack of material for 

 comparison,* 1 have been unable to accomplish much in the 

 w^y of constructive criticism. These notes are solely intended 

 to show how previous work must perhaps l)e modified in the 

 light of this fresh material from countries so little known (as re- 

 gards the Auchenorchynchi) as Eastern Australia and Viti. 



And what an extraordinarily rich fauna of Leaf-hoppers there 

 must be in Australia and the Southern Polynesian Islands! 

 Messrs. Koebele and Perkins collected but a few months at the 

 worst season of the year in the very places that an Entomologist, 

 not collecting for such an economic purj)ose. w(Mild avoid on ac- 

 count of their barrenness. 



Yet, these few months have produced nearly 500 species, al- 

 most all new. It is probably not too much to say that the Aus- 

 tralian Region (in the widest extent of the name) is supporting- 

 today a leaf-hopper fauna of 10,000 species. It must l)e es- 

 pecially rich in Derbidae, Achilidae, Tetigoniidae, etc. 



The region moreover demands the attention of Hemipterists, 

 since it appears to possess the oldest existing fauna in the world. 

 h is well known that the classification in all other orders of in- 

 sects had to be considerably modified when the Australian fauna 

 began to be worked out, and it will certainly be the case also 

 with the Hemiptera. Coding and Froggatt have recently tack- 

 led the work in earnest, and it is to be hoped that extensive col- 

 lections will be reaped before it is too late. 



I must maintain the four leading points enunciated on p. 296 

 as being established by a study of the imago and of the 

 nymphal instars in every detail of structure. 



(i) The highly sensorized condition of the antennae in the 

 adult and of almost the whole body of the nymphal instars, the 

 presence of tegulae, the remarkable carination of the liead and 

 nota, and the disposition of the parts of the former, the richl\ 



* I am indebted to my colleaKue. .Mi;, o. H. Swezey, for allowing nie ucce.ss to his 

 collections of Oliio FiilRoroids. and to my friend Mr. E. P. Van l>uzee for several examples 

 of Tetigfinioid and Asiraiid ycncra; to ilr. Ballon for Stenorranus i:a<c/in7-i7iora : and to 

 Dr. Melichai- for a few Sinhalese forms; otherwise beyond mv own collectings. I have 

 lieen compelled to rely on the written word. 



