25 



streak under the latéral margiii of the head. This character is, of 

 course, of no generic value, and in conséquence of this limitation 

 of the genus he referred only three Asiatic species to it, besides 

 the type. It has since been united with Nezara. Yet Acroslernuni is 

 in my opinion a perfectly valid genus, readily separable from 

 Nezara by the structure of the metasternal orificia which are always 

 of great importance in the systematic arrangement of the Pentato- 

 midae. 



Nezara Am. S. : Oriflcia brevia, latiuscula, médium metapleurse 

 non aut vix attingentia, apice abrapta et levissime elevata, in 

 rugam seu plicam non continuata, rarissime perbrevia, subauricu- 

 lata. 



Acrosternum Fieb. : Orificia in rugam seu plicam longam angus- 

 tam, apice acutam, angulum postero-lateralem mesopleure fere 

 rtttingentem, oblique extrorsum et antrorsum continuata. 



The conclusive proof that they are distinct gênera has been given 

 by Sharp (Trans. Ent. Soc. Lond. 1890, p. 406-408, pi. XIII, flg. 

 M, 12, 16, 17) who has studied in détail the inner maie génital 

 segment and its appendages of Nezara vir/dula ].., an unnamed 

 Acrosternum from Madagascar allied to acutum Dau.. (it is the 

 recently described A. spicatton Dist.) and the American Acroster- 

 num ynarginatum P. B. While the two geographically widely sepa- 

 rated species of Acrosternum are very similar in the structure of 

 the maie génital segment, the Nezara is in this respect so totally 

 différent that Sharp says he doubts whether they can be correctly 

 placed în the same genus. 



To iVezara belong the species placed by Stâl (Enum. Hem, V, 

 p. 91) in his division a of this genus. No American species, except 

 the cosmopolitan viridula, belong to Nezara. 



To Acrosternum belong the species of Stâl's division aa (loco cit.) 

 and ail American species wrongly placed by KiRKALDY(Cat., p. 116- 

 117) in the « typical subgenus » of Nezara (except viridula). 



Pellœa Stâl, which StAl regarded as a subgenus, is generically 

 distinct by the structure of the pronotal apical margin, the base of 

 the venter, and the quite différent coloration. 



Banasa Stâl (including Atomosira Uhl.) is distinct from Acro- 

 sternum by différent puncture and habitus; Rio Kirk. can be main- 

 tained as a subgenus of Banasa. 



I bave not seen Menida Gerstœckeri Bergr. since l described it 

 some twenty years ago, and the type is in the Paris muséum, but 

 although the apical margin of the pronolum is narrowly levigated 

 and slightly elevated, there can be no doubt that it is an Acroster 

 num allied to A, rinapsus Dall. 



