United States or Libya ? Vote for the TOP Country of the Week !
In this way I obtained some magnificent series of Anthidia and Megachiles, running up to a dozen. There was a melancholy side to this success. All my series, with not one exception, were ravaged by parasites. Both kinds were swarming with a colony of pigmy parasites whose name I have not yet been able to discover.
In those aerial nests, swinging at the end of a twig, not a Dioxys, a Stelis, an Anthrax, a Leucopsis, those dread ravagers of the other two Masons; never any Osmiae, Megachiles or Anthidia, those lodgers in the old buildings. The absence of the latter is easily explained. The Chalicodoma's masonry does not last long on its frail support.
The White-girdled Leaf-cutter likes the robinia, to which she adds, in lavish proportions, the vine, the rose and the hawthorn and sometimes, in moderation, the reed and the whitish-leaved rock-rose. I have not known her to use any other materials than the wild briar and the hawthorn. Incomplete though it be, this list tells us that the Megachiles do not have exclusive botanical tastes.
Knowing the points frequented by the two Megachiles, I planted in their work-yard, overgrown with briar and lilac, two outlandish plants which seemed to me to fulfil the required conditions of suppleness of texture, namely, the ailantus, a native of Japan, and the Virginian physostegia.
But the grey caterpillar, sacrificed one day, may be succeeded on another day by a green, yellow or striped caterpillar. There you have discernment, which is quite capable of recognizing the regulation prey under very diverse garbs. The Megachiles build their honey-jars with disks cut out of leaves; certain Anthidia make felted cotton wallets; others fashion pots out of resin.
The Megachiles affirm the exact opposite. They tell me that the animal, though invariable in the essence of its art, is capable of innovation in the details; but at the same time they assure me that any such innovation is sudden and not gradual.
The Osmiae make their partitions with mud or with a paste of chewed leaves; the Mason-bees build with cement; the Pelopaeus-wasps fashion clay pots; the Megachiles made disks cut from leaves into urns; the Anthidia felt cotton into purses; the Resin-bees cement together little bits of gravel with gum; the Carpenter-bees and the Lithurgi bore holes in timber; the Anthophorae tunnel the roadside slopes.
Here is the flora of the Megachiles in my neighbourhood, a very incomplete flora and doubtless capable of considerable amplification by future researches. The Silky Leaf-cutter gathers the materials for her pots, her lids and her barricades from the following plants: paliurus, hawthorn, vine, wild briar, bramble, holm-oak, amelanchier, terebinthus, sage-leaved rock-rose.
They consisted of stumps of the great reed of the south, open at one end, closed at the other by the natural knot and gathered into a sort of enormous pan-pipe, such as Polyphemus might have employed. The invitation was accepted: Osmiae, Anthidia and Megachiles came in fairly large numbers, especially the first, to benefit by the queer installation.
We must not allow this diversity to lead us to believe in changes of instinct: that would be to strain at a Gnat and swallow a Camel. The industry of the Megachiles, for instance, consists of manufacturing wallets with bits of leaves; that of the Cotton-bees of making bags of wadding with the flock gathered from certain plants.
Word Of The Day