OF AMERICA NORTH OF MEXICO. 165 



22. S. MARGiNATA, " glabra atra, thoracis inargine flauo." 

 Fabr. Eat. Sjst. Sup. 148. Sjst. El. 2, 831. 



Group 11. 



These genera have a close relation to the preceding group, and are distinguished 

 from it only bj the long last joint of the tarsi. The thorax is sometimes armed. The 

 ligula appears to be rarely emarginate, and the palpi are situated some distance in 

 front of the base of the raentum : the mentum is trapezoidal : in Compsosama the 

 ligula is however emarginate. The ungues are always simple. 



ONCIDERES Serv. 



Antennae teuues setacese, elongatce, subtus parce vix ciliatse. 

 Acetabula antiea ad prosterni marginem anteriorem fere extendentia. 

 Ligula Integra, medio subelevata. 

 Femora subclavata : tarsi articulo ultimo longissimo. 



The thorax in the large Mexican and Brazilian species is armed with a short spine, 

 in ours it is narrowed and slightly constricted behind, the sides are only a little 

 sinuous. The anterior acetabula are very large and extend as near to the anterior as 

 to the posterior margin of the presternum. 



1. 0. CINGULATUS, piceus, pilis cinereis fulvisque dense vestitus, thorace transverse, postice subangustato et 

 constricto, elytris punctatis versus basin scabris, minus dense cinereo-pubeseentibus, guttis rotundis fulvo- 

 pubescentibus adspersis, basi late, fasciaque pone medium leviter infuscatis, antennis vix annulatis. 

 Long. -GS. 



Hald. 52. 



Lamia clmjulata Say. J. Ac. Nat. Sc. 5, 272. 



Middle and Southern States ; the Southern specimens have the fulvous spots more 

 distinct, and the obscure bands scarcely visible: they are Oncideres ruhiginosus Dej. 

 Cat. This species is parasitic in Carya. I have one specimen found on Diospyros 

 virginianus, but I know not if the insect attacks that tree. 



MESOSA Serv. 



Antennae breviusculae, subtus (piDScipue ad articulorum apices) hirsutre. 

 Ligula non cmarginata. 



Acetabula antiea ad marginem prosterni anteriorem non approximata. 

 Femora non clavata; tarsi articulo ultimo mediocri. 



A short thick form of body is here assumed ; and the insect bears a very strong 

 resemblance to certain genera of Group 13, from which it is at once distinguished by 

 its angulated anterior acetabula, and large front. The thorax is slightly tumid on 

 the sides, in the species here described. In the European species the outline is quite 

 straight ; the front is slightly concave between the antennae. 



42 



