108 THE CANADIAN ENTOMOLOGIST. 



A CANADIAN TRIGONALYS. 



BY W. H. HARRINGTON, F. R. S. C, OTTAWA. 



Trigoiialys Canadensis, n. sp. 



Male. — Length, 10.5 mm. Black with yellowish markings. Head 

 transverse, as wide as thorax, about twice as wide as long when viewed 

 from above ; face above the antennte, and vertex, polished, impunct'ate, 

 without apparent sutures and with sparse blackish pubescence; the cheeks 

 and under surface with pubescence more dense ; clypeus polished ; palpi 

 slender; antennae as long as head and thorax, rather stout, eighteen- 

 jointed, segments subequal ; eyes small but prominent ; ocelli small, in a 

 triangle on a line with the posterior margins of the eyes. Thorax rugose 

 with coarse, irregular punctures, those of the pleura and pectus smaller 

 and more numerous ; posterior angles of prothorax yellow ; legs rather 

 slender, coxa and femora black, remainder yellow, the tips of tibise and 

 tarsi somewhat dusky ; wings subhyaline, with dark stain covering 

 marginal cell and extending slightly beyond each end of it, stigma and 

 costal nervures black, remaining nervures reddish, second and third sub- 

 marginal cells subequal ; scutellum abruptly rounded posteriorly, post- 

 scutellum yellow, prominent, subpyramidal, notched at apex, in suture on 

 each side several deep shining foveae ; metathorax very short and rounded 

 at sides, without prominent angles, a small yellow spot on each side. 

 Abdomen polished, impunctate, apparently with six segments ; second 

 segment as long as all the following and with a yellow central band, or 

 elongated spot on each side ; a yellowish spot at lateral base of segments 

 3 and 4, very faint on the latter ; venter slightly pubescent, with double 

 row of yellow spots on segments i to 5, largest on 2nd. 



This is the first record of the occurrence of any member of the 

 family Trigonalidte in Canada, and I am indebted for the privilege of 

 describing the specimen to Mr. Fletcher, who received it in Sept., 1893, 

 from Mr. Wilkinson, of Victoria, B. C. It was taken from the cell of a 

 wasp (probably Vespa occidentalis) which had built on his verandah, and 

 he had observed that the wasps were rapidly decreasing in numbers, 

 apparently from the presence of this parasite, and of a smaller species of 

 hymenopteron, of which, unfortunately, no specimens appear to have 

 been preserved. 



