This section is from the book "British Wild Flowers - In Their Natural Haunts Vol2-4", by A. R. Horwood. Also available from Amazon: A British Wild Flowers In Their Natural Haunts.
Emphasis has been laid upon the close ranks of the corn itself and the struggle of the plants towards the light. The cornfield is indeed extremely inaccessible for all classes of animal life; attention should be drawn to this aspect, and lists of animals noticed drawn up.
It is true that one may find a good many insects and other small animals in a cornfield especially associated with the ground flora, where beetles, spiders, and myriapods are not uncommon. Often one may see butterflies soaring over the cornfield, but few of them settle, and the food plants of their larvae are not usually cornfield species.
The night-flowering Catch-fly and the White Campion are exceptions to this rule that plants depending on Lepidoptera are absent from the cornfield. Cross-pollination by insect agency is on the whole rare.