AMERICAN HYMENOPTERA, 325 



A Contribution towards a knowledge of the Nearctic 

 Odynerinae. 



BY P. CAMERON. 



Having recently written papers on the Solitary Wasps of the 

 Soutliwest of the United States, in the collection of Prof. C. F. 

 Baker, for publication in the " Invertebrata Pacifica," I give here 

 some descriptions from other districts of the United States and 

 Canada. 



Syniniorplius cogitans sp. uov. 



Black, shiuing, an irregular mark, wider than long, on the top of the clypeus, 

 one of the same size over tlie antennae, a small cue behind the eyes, near the top, 

 a tiiangular mark on the outer edge of the pronotum, 2 marks narrowed ou the 

 inner side, ou the apex of the scutellum, a larger, oblique, conical mark below 

 the tegulse, a line, dilated backwards ou the sides, on the apex of the 1st abdom- 

 inal segment, a wider, more irregular one, on the 2ud and a narrower one, inter- 

 rupted in the middle, on the 4th, lemon-yellow ; the apex of the femora narrowly, 

 the 4 anterior tibiae, iu front, and the basal two-thirds of the hind tibise yellow, 

 the tarsi rufous yellow. Wings almost hyaline at the base, the apex fuscous 

 violaceous, the tegulte dark fuscous, lemon-yellow at the ai)ex. 9 • Total length 

 7 mm. 



Clypeus as wide as long, depressed at the apex, which is transverse, the centre 

 on the lower two-thirds strongly, deeply punctured ; the frontand vertex strongly, 

 closely punctured, the temples wide, rounded. Thorax about two and a half 

 times longer than wide, rounded at the base and on the sides of metanotuni. 

 Parapsidal furrows distinct. Basal half of mesonotum strongly, but not closely 

 punctured, the apical more weakly and much more sparsely punctured ; the apex 

 in the middle depressed, with two longitudinal keels. Scutelluni flat, the base 

 smooth, the apex rugosely punctured ; a wide, deep furrow down the centre of 

 the apical three-fourths. Scutellar depression with five keels, besides the outer 

 bordering ones. Post-scutellum coarsely, rugosely punctured at the base, its apex 

 smooth, bluntly rou!ided. Base of raetanotum coarsely, closely irregularly re- 

 ticulated, as are also the sides, which are not margined, the centre is minutely, 

 closely striated. Propleurai coarsely, rugosely puuctuied ; the mesopleurse behind 

 the yellow mark with large, clearly separated punctures, the apex above stoutly, 

 closely striated, the lower part coarsely aciculated ; the upper part of metapleurse 

 aciculated and bearing round, distinctly separated punctured. First abdominal 

 segment distinctly longer than it is wide at the apex; the basal slope forms a 

 longish triangle, and is aciculated ; the top bordering keel is smooth and curves 

 down slightly in the middle ; the longitudinal furrow is narrow and is placed in 

 a depression ; the 2nd is clearly longer than it is wide at the apex, is narrowed 

 at the base, which is aciculated and obscurely punetured ; the abdomen is as long 



TBANS. AM. ENT. SOC. XXXII. DECEMBER. 190G. 



