HEMIPTERA— HETEUOPTERA— PENTATOMID.E. 4 53 



Subfamily PENTATOMIDA Stal. 



This group is one of tlie most prevalent of the suofamilies of Heterop- 

 tera in the European Tertiaries, twenty-six species being found there, 

 which have been referred to six genera: ^Elia, one species, Eurydema, 

 our, Eusarcoris two, and Halys two, all from Oeningen, besides Penta- 

 toma, which has been accredited to Radoboj, Aix, Salzliausen, and amber, 

 but especially to Oeningen, where nine species have been recorded. 

 Besides these a species of Pentatoma has been described from Greenland. 



In our Western Tertiaries remarkably few examples of this group have 

 been recovered, considering its abundance in the Old World, but nearly 

 every specimen is generically distinct from every other, for we have but 

 thirteen species, and in only two instances have these more than a single 

 specimen each, yet so different are they that they must be separated into 

 ten genera ; only one of these, imperfectly known by a very remarkable 

 head, can be referred to an existing genus, for in all the scutellum is 

 remarkably triangular and equiangular and destitute of the apical exten- 

 sion common to living types. In this, as already stated, some of the Euro- 

 pean species appear to agree with them ; it should, however, be noted that 

 this agreement appears far more marked in Heer's direct illustrations of the 

 fossils than in his restorations of the same species. Our species all come 

 from Florissant, with a single exception. 



• Tahle of the genera of Pcntatomida. 



Intraocular part of head less tbau two aud a half times as long as broad. 



Apex of sciitelhini reaching distinctly less than half-way to the tip of the abdomen. 



Head in front of eyes quadrate, the tyluui and jnga of similar length 1. TrhoscliiKfiis. 



Head in front of eyes tapering, the tylum surpassing the jnga 2. Thntluschiatus. 



Apex of scutellum reaching half-way to the tip of the abdomen. 

 Thorax jess than three times as broad as long. 



Body regularly ovate throughout 3. Poteschislns. 



Body with parallel or nearly parallel sides. 



Head sUorter than middle of the thorax and more than half its width. .4. Cacoackhtiis. 

 Head longer than the middle of the thorax and slightly less than half as wide as the 



thorax 5, Matwoschistua. 



Thorax three or more than three times as broad as long. 



Body at least half as long again as the .width of the abdomen. 

 Posterior lateral angles of thorax prominent. 



Sides of thorax lu front of lateral prominences concave 6. PoHonchMus. 



Sides ot thorax In frout of lateral prominences convex 7. Prnlatomitrs. 



Posterior lateral angles of thorax not prominent H Tiroschistua. 



Body less than half as long agaiu as the width of the al)douien 9. TliUmmouchislKS. 



Intraocular part of head two aud a half times as long as broad 10. Alecucephala. 



