1S76.) 230 



ON CERTAIN BRITISH HEMIPTEHA-HOMOPTERA. 



BT JOHK SCOTT. 



Revision of the 'Family DELTOCEPnALii)^, xcith descriptions of new and hitherto 

 unnoticed British species. 



This forms the 3rd of the sub-genera into which Burmeister in 

 his " Genera Insectorum " divided his genus lassus. Of his remaining 

 sub-genus, Plafi/jfietojjius, there is no British representative known, 

 although, from the wide range of one of the species (P. undatus), it 

 might be expected to occur here. But by far the most perplexing of 

 the whole group is that with which I am at present dealing ; minute 

 in size, and as unstable in colour and markings (in many of the species) 

 as it is possible to conceive, I find it an almost hopeless task to convey 

 anything like certainty in the descriptions as to which species is meant, 

 although I have done my best to do so, and therefore a careful exami- 

 nation of the genitalia is alone sufiicient to enable students to deter- 

 mine between them. For those who do not work with the microscope, 

 but who do or can possess the " Verhaudlungen d. K. K. z.-b. Gesell- 

 schaft in Wien," vol. xix, in which is Dr. Fieber's Synopsis of the 

 European species, the examination of the form of the posterior margin 

 of the last segment of the abdomen of the $ of the various species, 

 and comparison with the figures which he there gives, will modify 

 considerably the difficulties encountered on the threshold of the task, 

 and this can be accomplished with the aid of an ordinary lens. These 

 insects are most generally met with by sweeping among heath, or in 

 meadows, or on the margins of fields and woods, and in some instances 

 occur in countless profusion. All our species may be said to consist 

 of two kinds, viz., green or yellow and oceUate, and I have so sec- 

 tionized them in the following paper, imperfect although I fear it is, 

 believing that more case will be experienced by those who try to work 

 them out by this thau any other method. 



Section A. 

 Green or yellow species. 

 1. Apex of the elytra without a black margin. 



Very pale green, slightly farinose. Face pale brown ; round the 

 upper margin a broad black line interrupted at the apex. 



Head — crotcn pale brownish-yellow, somewhat farinose ; width between the eyes at least 

 one-third shorter than the length down the centre ; sides between the anterior margin 

 of the ej'es and the apex equal to the breadth across the former ; on each side of the 

 apex a very short, slightly diagonal, black streak. Face pale brown, with a white cen- 

 tral longitudinal line, widest on the frons, and six or seven transverse white lines on 



