From Ferdinand von Mueller to the Royal Horticultural Society   [Sep 1880]

[The Australian Eucalypti appear to be peculiarly liable to the attacks of gall-producing insects, and to the assumption by the galls of extraordinary forms. The accompanying figure (fig. 98, p. 529), represents galls on a species of Eucalyptus forwarded (as were the galls figured at p. 405)1 by Baron Ferdinand von Mueller. The figure represents the galls of about their natural size. At first sight each gall reminds one of a distorted fruit or capsule, but Dr. Masters is of opinion [from their position]2 that they are not modified buds either of leaf or flower. On the twig before me the galls are placed unilaterally, with the exception of the lowest of the series. Each gall (dried) is somewhat olivaceous in colour (as in the leaves). Each measures about 10 lines in length, and about 5 in diameter. Each has four strong angular keels externally, which are continued into extraordinary processes about 2½ inches long, and slightly curved at the tips; occasionally one of these processes is absorbed or abbreviated, and in one instance a tendency to furcate is shown. They are extremely hard, and the walls are quite a line in thickness, and when cut a very strong odour, like that of intensified Black Currant, is very evident. The artist who drew the specimen pronounced the odour to be that of Black Currant plus Tom-cat.

Fortunately in this instance it is possible to fix with certainty the order to which the gall-maker belongs. Baron von Mueller extracted larvae from some similar galls, and forwarded them in fluid. They are lepidopterous. A well-grown larva is about an inch in length, pinky-whitish in colour, somewhat semi-transparent, and without markings, save that there are black dots on the spiracular region, independent of the black spiracles themselves; the head is pale, castaneous. There (fig. 97) are eight ventral (in addition to the anal) prolegs.]3

See M to the Royal Horticultural Society, March 1880 (in this edition as 80-03-00).

Brackets in source text.

The remainder of the article concerns the possible taxonomic position of the insect, and a note of the hymenopterous parasites found within each moth chrysalis.

Letter not found. The text given here is from 'Galls on Eucalytus' by R. McLachlan, Gardeners' chronicle, 23 October 1880, p. 528 (figure on p. 529). The correspondent is assumed to be the Royal Horticultural Society as other such specimens were reported in records of meetings of the Society's Scientific Committee. The consignment of galls was evidently later than of those reported upon previously and cited in the letter, and it is dated to early September as the latest likely date that it could have been sent for McLachlan to have examined them and prepared the report for this issue.

Please cite as “FVM-80-09-00c,” in Correspondence of Ferdinand von Mueller, edited by R.W. Home, Thomas A. Darragh, A.M. Lucas, Sara Maroske, D.M. Sinkora†, J.H. Voigt† and Monika Wells accessed on 5 June 2025, https://epsilon.ac.uk/view/vonmueller/letters/80-09-00c