NOTES ON HYMENOPTERA. 83 



are still to be found there in diminished numbers. One rarity, 

 Tiphia miuvfn, is usually to be captured sparingly in the 

 month of June. Last season, however, my attention was 

 directed by Mr. Baly to the appearance of that species in un- 

 usual numbers. On visiting the spot pointed out, I literally 

 found them in hundreds, where, even in the most favourable 

 seasons, the capture of a dozen examples would have been 

 considered a great harvest. Tiphia minuta may be truly 

 called a sun-shiner ; it runs with great rapidity, occasionally 

 taking wing and flying over and near the ground, gyrating 

 in circles with great rapidity. On the sun being momentarily 

 obscured they drop instantly to the ground, a few seconds 

 sufficing for their burying themselves in the sand, where 

 they lie motionless until the sun again shines forth. On no 

 previous occasion have I seen this insect in numbers at all 

 approaching the multitudes observed on this occasion. 



The typical species of the genus, llphia femorata, also 

 occasionally appears in vast multitudes, and is usually a much 

 more abundant insect than T. minuta. In the year ]858 

 I found T. femorata in incalculable numbers at Pakefield, 

 near Lowestoft ; some of the heads of the wild carrot were 

 covered with them, but although I searched the same spot 

 during the four following seasons but few were observed ; and 

 in 18f>3, even in the finest weather, at the proper period of 

 the season, not more than two or three could be found. 



It has no doubt been observed, that for the last three or 

 four years I have commented upon the almost total disap- 

 pearance of certain species o^ Andrenidce from their former 

 haunts near the metropolis, whej'e year after year they for- 

 merly appeared in great abundance. The past season was 

 apparently in every respect so congenial and suitable to 

 these insects, that I confidently expected their appearance 

 in some abundance, but I have been greatly disappointed, 



g2 



