14 THE CANADIAN ENTOMOLOGIST. 



This species is related to O. sonore?isis, Ckll., and O. tiigrocinda, 

 Ckll., but has a much longer ovisac than either of these. The arrange- 

 ment of the subdorsal lamellae is also different, and more black shows on 

 the dorsum than in either of those species. 



NOTE ON TRIGONALYS CANADENSIS, Hargtn. 



BY GEO. W. TAYLOR, F. R. S. C, GABRIOLA ISLAND, B. C. 



Wishing to obtain a series of males of our common ground wasps, I 

 paid a visit on the afternoon of October 21st to a large nest of Vespa 

 ocddentaHs, Cresson, that I had noted some time previously near my 

 house. The day was dull and the wasps sluggish, but quite a number of. 

 males and perfect females were crawling about around the entrance to the 

 nest. Among the wasps were some specimens of a conspicuous ypllow 

 and black Hymenopteron unlike anything that I had seen before. I 

 secured nine specimens, all males, aad on my return home easily made 

 out by the help of Cresson's Synopsis that the insects belonged to the 

 genus Trigonalys. The next step was to turn to Harrington's paper in 

 the Can. Ent., XXVIII., page 108, and compare my specimens 

 with the description of the unique Trigonalys canadensis. Unfortunately, 

 all my specimens were males, while Harrington's type was a female. 

 Consequently the description did not quite fit, but on the following day I 

 took three females and satisfied myself that the species I had found was 

 the genuine T. cajiadensis. 



As the wasps' nest, and a second one not 50 yards away from it, 

 were quite near to my house I was able to visit them several times each 

 day, and my captures of Trigonalys were as follows : 



