VI PREFACE. 



it may be that tlie discovery of many new and allied species would 

 show that his prescience had, in some instances, seized upon the 

 requisite generic characters. 



rior's ' Eliynchoten Livlands,' published in 1860, is worked out 

 in a masterly manner and with a philosophic conception, but from a 

 different point of view to Fieber's work. Having more limited 

 materials to deal with, the author has given more full and me- 

 thodical descriptions ; he has aimed at making as few genera as 

 possible, and has, consequently, placed generic value so high that 

 he has had to employ sub-genera, a device which, to say the least, is 

 very cumbrous. To Flor belongs the credit of applying to the 

 purpose of classification throughout the order the characters 

 afforded by the structure of the abdomen, especially of the " genital 

 segments." 



The materials for the present work have been collected by us in 

 the southern counties, chiefly in the vicinity of London, during four 

 or five years of almost undivided attention to the order, and we are 

 also indebted to the liberality of a few friends for species from a 

 distance. "When Hemiptera shall be collected over a larger area, 

 ■with the assiduity devoted to Coleoptera and Lepidoptera, there 

 cannot fail to be a large addition to the number of our known 

 species. 



The plan of the work is, first, the separation into Divisions and 

 Subdivisions (pp. 10, 11). The Subdivisions are assorted into Sec- 

 tions, and these again into Families, comprising the leading points 

 of the genera therein denoted (pp. 11 — 50). Then follow the 

 Genera and Species (pp. -51 — 617) ; the Section and Family to which 

 they belong being indicated by the heading of the pages. All the 

 descriptions (with the very few exceptions mentioned in loco) have 

 been made from actual specimens. The synonymy has been ren- 

 dered as full as is consistent with accuracy, the preference always 

 given to the oldest name, and doubtful citations and references to 

 mere lists omitted. The localities given are those of which we are 

 certain, but many of the species doubtless exist elsewhere. The 



