(11/9.  ‘Gardeners’ Chronicle’ 1844 page 374.) I have known humble-bees to visit the flowers of Lobelia fulgens in one garden and not in another at the distance of only a few miles.  The cupful of nectar in the labellum of Epipactis latifolia is never touched by hive- or humble-bees, although I have seen them flying close by; and yet the nectar has a pleasant taste to us, and is habitually consumed by the common wasp.  As far as I have seen, wasps seek for nectar in this country only from the flowers of this Epipactis, Scrophularia aquatica, Symphoricarpus racemosa (11/10.  The same fact apparently holds good in Italy, for Delpino says that the flowers of these three plants are alone visited by wasps:  ’Nettarii Estranuziali, Bulletino Entomologico’ anno 6.), and Tritoma; the two former plants being endemic, and the two latter exotic.  As wasps are so fond of sugar and of any sweet fluid, and as they do not disdain the minute drops on the glands of Prunus laurocerasus, it is a strange fact that they do not suck the nectar of many open flowers, which they could do without the aid of a proboscis.  Hive-bees visit the flowers of the Symphoricarpus and Tritoma, and this makes it all the stranger that they do not visit the flowers of the Epipactis, or, as far as I have seen, those of the Scrophularia aquatica; although they do visit the flowers of Scrophularia nodosa, at least in North America. (11/11.  ’Silliman’s American Journal of Science’ August 1871.)

The extraordinary industry of bees and the number of flowers which they visit within a short time, so that each flower is visited repeatedly, must greatly increase the chance of each receiving pollen from a distinct plant.  When the nectar is in any way hidden, bees cannot tell without inserting their proboscides whether it has lately been exhausted by other bees, and this, as remarked in a former chapter, forces them to visit many more flowers than they otherwise would.  But they endeavour to lose as little time as they can; thus in flowers having several nectaries, if they find one dry they do not try the others, but as I have often observed, pass on to another flower.  They work so industriously and effectually, that even in the case of social plants, of which hundreds of thousands grow together, as with the several kinds of heath, every single flower is visited, of which evidence will presently be given.  They lose no time and fly very quickly from plant to plant, but I do not know the rate at which hive-bees fly.  Humble-bees fly at the rate of ten miles an hour, as I was able to ascertain in the case of the males from their curious habit of calling at certain fixed points, which made it easy to measure the time taken in passing from one place to another.