On another occasion, in June, on the tableland of Saint-Amans, a neighbour of the Ventoux, at a height of 2400 feet, I witnessed a similar gathering, only much less numerous. At the most prominent part of the plateau, on the edge of a bluff of perpendicular rocks, stands a cross with a pedestal of hewn stone. On each face of this pedestal and on the rocks supporting it, the same Beetles, the Seven-spot Ladybirds of the Ventoux, had gathered in their legions. The insects were mostly stationary; but, wherever the sun beat at all fiercely, there was a continual exchange between the newcomers, anxious to find room, and the old occupants of the wayside cross, who took to their wings only to return after a short flight. Nothing here, any more than on the summit of the Ventoux, was able to tell me the cause of these strange meetings on arid spots, containing no Plant-lice and possessing no attraction for Ladybirds; nothing suggested the secret of these crowded gatherings on masonry situated at a great height. Were these again instances of entomological migration? Were they general musterings, similar to that of the Swallows on the day before their common departure? Were they meeting-places whence the swarm of Ladybirds was to make for some district richer in edibles? It is possible, but it is also very extraordinary. The Ladybird has rarely been noted as a devotee of travel. She seems to us a very stay-at-home creature when we see her butchering the Green-fly on our rose-trees and the Black-fly on our beans; and yet, with her short wings, she holds plenary assemblies, in immense numbers, on the summit of Mont Ventoux, where the Martin himself ascends only at moments of violent energy. Why these meetings at such altitudes? What can be the reason of this predilection for blocks of masonry? CHAPTER XIII THE AMMOPHILÆ A slender waist, a slim shape; an abdomen tapering very much at the upper part and fastened to the body as though by a thread; black raiment with a red sash across the belly: there you have a summary description of these burrowers, who are akin to the Sphex in form and colouring, but differ greatly from them in habits. The Sphex hunt Orthoptera—Locusts, Grasshoppers, Crickets—while caterpillars are the quarry of the Ammophilæ. This change of prey in itself suggests new methods in the lethal tactics of instinct.