28 Mr. J. O. Westwood's Description of a 



longiori subcylindrico, in canali ad latera thoracis haud 

 receptee. Caput brevius, antice bifidum. Thorax angulis 

 posticis acutis prominuHs. Scutellum triangulare, postice 

 acutum, et ad medium abdominis fere attingens. Hemely- 

 trorum venae fere ut in Macrocephalis veris dispositae (fig. 

 7 b). Abdomen ovatum, planum, lateribus in medio in angulum 

 baud productis, thorace multo latius (fig. 7 c, extremity of 

 the female abdomen). 



Sp, 1. (12.) Macrocephahis (Hemithyreus) cylindricornis. (n. s.) 

 Tab. 2, fig. 7. 

 Totus pallide rufescenti-lutescens, punctatus, pedibus nonnihil 

 pallidioribus, membrana hemelytrorum hyalina, thorace pos- 

 tice vix elevato, angulis posticis prominulis, acutis. 

 Long. Corp. hn. 5\. 

 Habitat ignotus. In Mus. Reg. Parisiis. 



III. Description of a new Sub-Genus of Exotic Hemip- 

 terous Insects. By J. .O. Westwood. 



[Read 6 November, 1837.] 



Since the last meeting of this Society, — at which I read a mono- 

 graph on the genus Macrocephalus of Swederus, (a group dis- 

 tinguished by the large size of the scutellum, which entirely 

 covers the abdomen), and in which it became necessary to esta- 

 blish a sub-genus upon an insect in the national museum of 

 France, having the scutellum only extending half the length of 

 the abdomen, and very acutely pointed at its tip— I have met 

 with another singular group belonging to the same genus in the 

 essential characters of the form of the body, and in the general 

 disposition of the veins of the apical membrane of the hemelytra ; 

 but likewise differing in the small size of the scutellum, which is 

 rounded at its tip, and which cannot be associated with the sub- 

 genus Oxythyreus above mentioned. From the obtuse form of 

 the short scutellum, which is its most characteristic distinction, it 

 may be named subgenerically 



Amblythyreus. 

 Corpus planum, lateribus valde dilatatum. 

 Caput angustum, oblongum, apice bifidum, oculis lateralibus, 

 ocellis 2 posticis. 



