WILLIAM AMBEOSE CLAEKE 167 



no case did I see a bee go from one species to another. In 

 summer wild bumble-bees do cross from species to species. Here 

 is the first record I can put my hand on : " Bombus lucorum, 

 23. 8. 1910, crossed from Centaurea nigra to Leontodon autmnnalis. 

 It was seeking honey in both cases." Was it feeding itself rather 

 than gathering food for others ? In my experience hive-bees do 

 not do so ; neither early nor late in the season have I observed it 

 in forty years. An old bee-keeper once told me that neither honey 

 nor bee-bread would keep if they were to do so. 



Taking the flowering season throughout, I estimate that twenty- 

 four flies (Diptera) visit the flowers of our whole flora for each 

 insect of all the other orders put together, the Thysanoptera 

 excepted. When it is on the wing in the summer heat Thrips is 

 on every flower, even those of the simplest grasses, in countless 

 numbers. The number of flies that visited flowers was most 

 astonishing to me when I first discovered the fact. In mid- 

 summer, when bees and beetles are most active and common, the 

 proportion, though high, is nothing like one to twenty-four, but 

 later in the season the notes soon run the other way. By mid- 

 October the bees have practically ceased to work, but the flies 

 continue as long as the flowers last, nearly up to Christmas in 

 open sunny seasons. For example, on the 16th of last October 

 I noted in a two-mile walk, on two soils, thirty-seven species in 

 flower in this parish. A bee was on one species, a fly or flies on 

 twenty-six, and there were as many as three species of flies on 

 one flower, on which there were five altogether. Looking at the 

 question of insect visitors in the light of a life-interest in the 

 subject, I am inclined to agree with Andrew Knight (1799), that 

 " in no plant does self-fertilization occur for an unlimited number 

 of years"; not even in cleistogamous species as we call them. 



WILLIAM AMBEOSE CLAEKE. 



(1841-1911.) 



Another of the supporters of this Journal and of the friends 

 of its Editor has been removed from among us in the person of 

 William Ambrose Clarke, who died at Oxford on the 23rd of 

 February. He was born at Hinckley, Leicestershire, on February 

 6th, 1841, his father, the Eev. T. A. Clarke, being then curate at 

 Stapleton. He was articled to Mr. Peter Awdry at Chippenham 

 and practised for about twenty years as a solicitor, chiefly at 

 Chippenham, of which town he was Mayor in 1879. Here he 

 became interested in botany, and was associated with the Eev. 

 T. A. Preston, then at Marlborough, in investigating the county 

 flora, his help l)eing duly acknowledged in the Flora of Wilis, 

 published by Preston in 1888. His first communication to these 

 pages was in 1887 — a brief note recox'ding certain additions to the 

 county flora as then known. 



In January 1892 Clarke married Miss Emily S. Ward, daughter 

 of the Vicar of Great Bedwyn, and in October of the same year 



