Notes on the Vegetable Caterpillar.

Transactions and Proceedings of the Royal Society of New Zealand, Volume 29, 1896, Page 608

3.“Notes on the Vegetable Caterpillar,” with specimens, by Mr. Charles Fitton; communicated by G. V. Hudson. The author contributed a number of fine specimens of the dried caterpillars, and also a number of live ones, with notes as to their mode of occurrence; but these all proved to be of species that were well known not to be true vegetable caterpillars, the moth or imago state of which had still to be discovered. Mr. Maskell wished to say only a few words, not about the specimens or the notes, but by way of a mild protest against the manner in which this subject, originally brought forward by him in 1894, had been ignored in favour of the discussions so frequently taking place as to this caterpillar itself. In 1894 he incidentally brought in this insect as an illustration, and only an illustration, of what he, and, as he gathered at the time; Sir J. Hector, Mr. Kirk, and Mr. Hudson also, considered a most important question—the assistance given to tree- and fruit-growers by certain fungoid organisms which killed injurious insects. That question had since been taken up very seriously in many other countries, but in New Zealand, because Sir W. Buller chose to raise what he (Mr. Maskell) said was a perfectly trivial and unimportant issue, the really important question had been obscured, and, although they had had this vegetable caterpillar constantly brought forward, nobody seemed to care for anything but the merest trivialities in connection with it. It was necessary to point out, in the interests of tree-growers in the colony, that

the really important part of the thing was not the caterpillar, but the fungus which killed it, and he was sorry that, with our Agricultural Department, and the Lincoln Agricultural College, and professors of biology all over the country, nobody seemed inclined to take up this economic side of the question. Mr. Tanner said it was a pity that the true species to which the vegetable caterpillar belonged could not be discovered. Ha had lately taken a great interest in these boring insects, as they had commenced to attack his trees. Mr. Hudson said that the real point to be determined in connection with the subject of the vegetable caterpillar was the discovery of the true species of Lepidoptera to which it belonged. He was perfectly certain that it was not Hepialus virescens, whose larva was a tree-borer, but it would probably prove to be one of the species of the genus Porina, the larvæ of which were subterranean. With regard to Mr. Maskell's regret that so much attention had been given to this insect by the members of the Society, to the exclusion of the economic study of the various fungi which destroyed insect-pests, he thought the investigation of this cater-pillar was a matter of great scientific interest, and was therefore a most suitable subject for the Society—far more so, in fact, than mere questions of economic entomology and fruit-culture. Mr. T. Kirk agreed with Mr. Maskell that the economic side of the question did not receive sufficient attention. What was required really was an expert vegetable pathologist, who could devote his whole time to such work as this. Credit was due to those who had done so much already in this branch of science, but they had no time to go specially into the matter. He was sorry credit had not been given to Mr. Hamilton, who had first discovered the little beetle Vedalia, which had been of so much use in destroying the fluted scale. Was Mr. Hudson quite sure that Hepialus virescens was the larva that bored? There was a great deal to be learnt regarding the life-history of these borers. The green moth bored into the hardest timber—the puriri. Mr. Tregear said that Mr. Tanner was like a great many others in this country—they only took an interest in such matters when it affected them personally. It was a pity that farmers and those interested did not come forward and assist those who were devoting their time to this valuable work of investigation. Mr. Maskell, in answer to Mr. Kirk, said the appointment of a vegetable pathologist was just the very thing he had been advocating, and it was what other countries had done. As regarded the beetle usually called Vedalia, and its destruction of what Mr. Kirk termed the “fluted scale,” he differed entirely from Mr. Kirk. Whether Mr. Hamilton ever saw Vedalia or not, before Mr. Koebele came he certainly never said anything about it, and the credit was justly and rightly given in every country in the world to Mr. Koebele, the man who, finding Vedalia, first in Australia and secondly in New Zealand, knew how to make practical use of the discovery, and went practically to work with it. It was he, and he only, who cleared California and other countries from Icerya, and he, and he only, deserved the credit. Mr. Travers thought the moth that was converted into the vegetable caterpillar took the fungi while feeding. There were several species that were attacked by the fungi. He called attention to the splendid collection of vegetable caterpillars on the table that had been secured and presented to the Museum by Mr. Fitton. Mr. Hudson, in answer to a question by Mr. Kirk, said that the larva of Hepialus virescens fed on many forest-trees. He bad found them in Aristotelia racemosa, Leptospermum ericoides, and several other trees the names of which he was unacquainted with.