151 



and Lewis. Mr. Walker's Catalogue enumerates 145, but of these 

 many will be found to be only varieties, and some {Penthimia atra, &c.) 

 are only entered provisionally, as likely to be discovered here after 

 further research. I have been enabled, after about two years of not 

 uninteresting labour, but with very moderate opportunities of travel, 

 to verify a goodly number of species. Many more may be detected if 

 other collectors can be induced to take up the subject, which, my ex- 

 periences enable me to assert, will be found full of interest. 



The genera Deljjhax, lassus, and Eupteryx {Typhlocyha) ,VkYQ rich in 

 species, and I cannot flatter myself that one half of these have ever 

 fallen in my way.~ The same groups are naturally those in which the 

 verification of sjjecies is most difficult. The only complete work whose 

 critical accuracy can be relied on, is Flor's " Bhynchoten Lievlands,''' 

 vol. ii., from which I have derived much valuable information. Another 

 work of great partial utility is Kirschbaum's " Die Athysanus-Arten 

 der Gegend von Wiesbaden," pviblished in 1858. Curtis's British En- 

 tomology contains some well-known and much admired figures, but the 

 text, written for the most part without reference to previously existing 

 descriptions, is full of embarrassment and error. But the enumeration 

 of authorities is no part of my purpose ; they can easily be found in 

 Hagen, and I shall give, under each species, a reference to the most 

 satisfactory description that can be foimd. Neither is it my object to 

 repeat generalities often written before, and which are accessible to 

 every one. Time and space alike forbid me to attempt a monograph : 

 I shall therefore content myself with diagnostic outlines, specially in- 

 tended for the discrimination of species, together with notes upon 

 synonymy (especially if unpublished), localities, and points of difficulty. 

 The only collection of these insects, besides my own, with which I have 

 made profitable acquaintance, is that of Mr. Douglas, which he has 

 most liberally entrusted to my keeping for more than a year : it con- 

 tains several species to which I could not otherwise have gained access. 

 I need hardly say that a mere Prodromus like the present can in no 

 way interfere with the value of that complete work which it is to be 

 hoped will one day result from the labours of the Entomologist above- 

 named, in conjunction mth Mr. Scott. If any other collectors can 

 hereby be induced to accumulate materials and information in aid of 

 such a future monograph, I shall not have laboured in vain. The few 

 genera to which our indigenous Homoptera Auclienorliyncha are referred 

 will easily be found in numerous works ; it will sufiice here to give 

 them syuoptically, as follows : — 



