ODYNERUS. 253 



roaxime acutis marginato; abdomine conico, basi acute truncato ; seg- 

 mentornm 2'-4' margine grosse punctato; 2' et 3" reflexo; scapo subtus, 

 macula frontali, oculari, post-ooulari, pronoti margine antico, post- 

 scutello, tegulis, macula snbalari et utrinquemetanoti sammi, abdominis 

 segmentorum l'-3" marginibus, flavis ; prirni fascia utrinque aucta ; 

 pedibus et mandibulis ferrugineo- et flavo-variis ; alis int'uscatis violas- 

 uentibus. J • Clypeo nigro, flavo-binotato ; % clypeo llavo. 



Variat signaturis plus minusve fulvis (Am. borealis). 



Varietas Mexicana. — Nigro et rufo-variegatus, vertice nigro ; antennarum 

 articulis 1°, 2° ferrugineis ; pronoto, macula snbalari, tegulis, scutellis, 

 metanoti lateribus, rufis v :1 flavo-variis; abdomine rufo; segmentorum 

 limbo flavo-vario; l 1 , 2' basi nigro-angulato, pedibus rufis. — % . Clypeo, 

 capitis signaturis et scapi fascia, flavis ; pronoti limbo, scutellis, macula 

 subalari et tibiis aurantiacis. 



9 . Total length, 13-14 mm. ; wing, 10-11 mm. 

 £ . Total length, 11 mm. ; wing, 8 mm. 



Odyn. Hidalgi Sauss. Rev. et Mag. de Zool. IX, 1857, 275 (var). 



Appearance of a Rhynchium, but the mouth quite as in Ody- 

 neras; the joints of the maxillary palpi becoming regularly shorter 

 from the first to the last. 



Clypeus punctured, widely truncate, its inferior part rather 

 flattened and laterally bicarinate. Thorax in the form of an 

 elongate square, not contracted posteriorly, densely and coarsely 

 punctured. Post-scutel sharply truncate, strongly crenulate. 

 Metathorax very rough on its superior and lateral face ; its 

 posterior concavity occupying its whole width, shining, strigose, 

 margined with very sharp edges, which form on each side a very 

 strong dentiform angle, and which terminates superiorly in two 

 eminences separated from the post-scutel by two deep fissures. 

 Abdomen silky, quite conical, not ovate ; its first segment large, 

 as wide as the second, sharply truncate anteriorly ; the margin 

 of 2d and following segments quite coarsely cribrose; the border 

 of the 2d and 3d reflexed but not channelled. Mandibles, a 

 frontal mark, inner orbits, post-ocular fascia, scape of the antennae 

 beneath, anterior margin of prothorax, a spot beneath the wing, 

 tegulas, post-scutel, a mark on each superior angle of metathorax, 

 yellow or rather fulvous ; segments 1-3 margined with yellow, 

 the fascia of the first much widened on the sides or fused with an 

 oblique fascia, often rufous. Legs fefruginous, black at base; 

 tibiae with a yellow line, or entirely yellow. Wings infuscated, 



