160 TERTIARY RHYXCHOPHOROUS OOLEOPTERA. 



Family ^T^THRIBTD^E. 



In the American Tertiaries tliis family is nnnsnally well developed, its 

 |)r<.|i(irti()nal rcpivsciitation being- considerably above what exists to-day. 

 The relative nmnbers of the different tribes are similar to what we now 

 hnd, and all the tribes are present except the Xenorehestini, which is tlie 

 sniallesT to-dav. The nnmliers of the Tropiderini, however, are above 

 their })resent pr(,)portion, and those of the Arjeocerini below it. In the 

 European Teitiaries neither the Tropiderini nor the Xenorehestini occur, 

 while the. actual numbers in the other groups are precisely as in the Amer- 

 ican rocks. The total number of European fossil species is scarcely more 

 than half that of the American. 



Tribe TROPIDERINI. 



This tribe is whoUv wanting- in the European Tertiaries, but is very 

 well represented in ours, liaving- five species of four genera, of which two 

 from Florissant, with one .species each, represent extinct types, wliile tlie 

 others are referred to Tropideres, one species each from Florissant and 

 Green Eiver, and Hormiscus from Clreen River. 



SAPERDIRHYNCHUS (Saperda, nom. gen., fSvyxo?), gen. nov. 



This striking genus of Anthribidie d(»es not fall in any of the gi-oujis now 

 recoo-nized as living in North America, but rather belongs to one allied to 

 our Ischnoceri termed Discotenides by Lacordaire: for the immensely long- 

 antenna' are inserted on the sides of the rostrum, the antennal scrobes are 

 circular and termiiial, the rostrum is at base smaller than the head, the eyes 

 are rounded and not longitudinal, and the prothoracic ridge is prebasal. 



This group, as defined bv Lacordaire in 1S6(), consisted of only three 

 fj-enera, two of which were found in islands of the South Pacific ocean, the 

 third, Discotenes, in Brazil. The present forni is not very close to that 

 o-enus, having a much shorter thorax, and autennse of different construction, 

 somewhat resembling Cerambyrhynchus, a genus of another group found 

 onU' in the Pacific islands. The following are some of the details of the 

 stracture of the fossil type. 



