2IO ENTOMOLOGICAL NEWS. [May, '15 



low the eyes their vertical width is generally slight, as in fig. I 

 (genae loiv), but sometimes {e. g. in certain Restheniini), 

 their width is great and may be equal to the vertical diameter 

 of the eyes, as in fig. 9 {genae high.). The bucculae {Wan- 

 genplatten) are thin ridge-like plates partially enclosing the 

 base of the four-segmented rostrum or beak. The gula 

 (Kehle) is the posterior median part of the head below. As 

 this part varies greatly in extent and position in diflferent spe- 

 cies, it furnishes valuable taxonomic characters. In the 

 Miridae the antennae, fig. 8, always consist of four segments, 

 but otherwise, by their great diversity in form, vestiture, and 

 proportions, they present important and easily observable 



criteria. 



The Prothorax. 



The anterior margin of the prothorax in certain groups is 

 provided with an apical stricture, a complete collar-like an- 

 nulus set oflF by an impressed line, figs, i, 7, 9. In other 

 groups, for instance in the tribe Mirini, the apical stricture 

 is lacking, although sometimes a false and incomplete stricture 

 is formed by the anterior margins of the calli and the humeral 

 impressed lines, as in Miris, fig. 6, The coxal cleft, fig. i, also 

 produces at times the impression of a stricture when viewed 

 laterally. In all cases the presence or absence of a true apical 

 stricture should be carefully noted, as this character is of 

 major importance in classification. The calli are two more or 

 less raised areas situated anteriorly on the pronotum, figs. 6, 7. 

 The prostemal xyphus is a part of the prosternum appearing 

 as a triangular plate between the anterior coxae. In Adelpho- 

 coris it is limited in front by the apical stricture and is concave 

 with raised margins, while in other groups it may be convex or 

 even conical and without raised margins, thus affording im- 

 portant taxonomic characters. 



The Mesothorax. (Plate vii, fig. i.) 



The pleural region is very clearly divided by an oblique line 



into two parts, furnishing one of the distinctive characters of 



the Miridae, these structures, when present, being much less 



clearly defined in other families. The larger and antero-in- 



