INTRODUCTION. 



By H. W. Bates, F.liS. 



The total number of species of Insecta and Araclinida collected by 

 Mr. Whyinper during his journey in Ecuador amounts to about one 

 thousand. Unfortunately it has been found impossible to induce 

 specialists to work up the whole of the grou[)s for the })urpose of the 

 present volume ; several important families and whole orders remain 

 unnamed, and are therefore for the present unavailable in aiding us to 

 form some idea of the nature and relations of the Faiuia of the Ecpia- 

 torial Andes. A rough estimate has been made of the numbers of 

 species in the missing groups. Thus Baron von Osten Sacken, on look- 

 ing over the Diptera, considered them to number about 100; Mr. 

 Druce, who partial]}' determined the Moths {LepkUptera Ileterocera), 

 found 44 species ; the Hymenoptera (exclusive of the Ants) appear to 

 be scared}' less numerous than the Diptera, and the Spiders comprise 

 not fewer than 200 sj^ecies. 



The Orders and Families of the Insecta class enumerated or described 

 in this Supplementary Appendix comprise 359 species. Of these no 

 fewer than 131 are new to science, and many of them are so distinct 

 that 14 new genera have had to be instituted for their reception. 



So much interest attaches to the nature of the Insect Fauna of 

 high altitudes in the Equatorial zone of the Andes, and to its relations 

 to the Faunas of Chili and Temperate zones of North America and 

 Europe, that it wouLl be undesirable to let the occasion pass of ana- 

 lysing Mr. Wlnmper's collection with this view, notwithstanding that 



p. 



