"A moth from the larvæ also accompanies the above, for I have fully satisfied myself of their identity. In 1836 I kept the larvæ under glasses, and fed them with the leaves of kumara (much to the annoyance of the natives), until the perfect insect was produced. There cannot reasonably exist a doubt that this insect deposits or drops some of her eggs on the branches of the raataa (Metrosideros robusta, A.C.), beneath which tree alone the Sphæria robertsii has hitherto been found, when they (the larvæ) fall to the earth beneath, die, and the Sphæria is produced.
"I think I can offer a fact for consideration relative to their being only (or chiefly) found beneath Metrosideros robusta. One fine evening last summer, when enjoying, as usual, a promenade in my garden, just as the sun had set, I was admiring the splendour of some plants of Mirabilis, which had just unfolded their scarlet petals. Suddenly several of these moths made their appearance, darting about the plants in every direction, pursuing one another, and eagerly striving to obtain the honey which lay at the bottom of the perianths of the Mirabilis. From this plant they flew upwards to the flowers of a stately Agave (A. americana), where, being joined by other moths, their congeners, their numbers soon increased; and thus they continued to enjoy themselves every evening during the whole season. The inference I deduce is this, that the M. robusta, blooming at this season, having scarlet flowers which abound in honey, becomes the centre of attraction of these insects—increased, too, by its densely crowded coma of inflorescence, more particularly so from the blossoms being always at the extremity of its branches; by which, and by their colour, this tree may at once be distinguished from the other denizens of the forest, even at a great distance.
"The larva whereon the Sphæria is found, when first taken out of the earth, is white internally, and appears solid and succulent. A finely-cut slice, when held against the light, presents a beautiful appearance."
I may further add that, 25–30 years back, I had a honeysuckle (Lonicera periclymenum) trained round the doorway of a house in my garden. This plant flowered abundantly in the summer, and it was interesting and curious of an evening to sit on the step (as I have often done) and watch those large moths (Hepialus); they would visit the plant in great numbers, and unrolling their long probosces, probe the flowers to get at the honey, passing quickly from flower to flower, and continually coiling and uncoiling their long trunks with great rapidity; they never lighted on the plant, and all the time kept up a tolerably loud humming noise from the quick and incessant vibrations of their wings, which, indeed, drew the attention of the cats, who often, in consequence, captured them.
