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PACIFIC SCIENCE, Vol. XXI, January 1967 
tributed by the swollen and fused petioles. 
These leaf parts are the nearest to the larva 
which occupies the former site of the shoot 
growing point. 
Substances emanating from the larva might 
tend to stimulate growth in basal parts of a 
rudimentary leaf and these regions might un- 
dergo cell division and growth at the expense 
of other parts of the unformed leaves. Fusion 
of the basal parts of rapidly multiplying leaf 
primordia could readily occur, assisted possibly 
by wound hormones and larval secretions. These 
would be free to operate without the overriding 
influence of the shoot apical meristem. 
In paraffin sections stained in Safranin and 
Fast Green, the salivary glands of larvae show 
characteristic giant cells with banded polytene 
chromosomes. 
The synthetic activities of the salivary gland 
cells not only may assist feeding of the larvae 
but also may provide the secretions which are 
responsible for the transformation of presump- 
tive leaf primordia to galls (Mani, 1964). 
SUMMARY 
A bud gall of My r sine australis (A. Rich.) 
Allan caused by a gall midge is reported for 
the first time. 
The galls are composed of modified leaves j 
which form the walls of an urnlike structure | 
enclosing the midge larvae or pupae. 
The larvae feed on proliferating chlorophyl- 
lous tissue which lines the larval cavity. 
During the development of the gall from a 
shoot bud, the apical meristem is destroyed by 
the larvae, and the leaf rudiments undergo | 
transformation and fusion. 
REFERENCES 
Allen, H. H. 1961. Flora of New Zealand, 
Vol. 1. Gov’t. Printer, Wellington. 
Johansen, D. 1940. Plant Microtechnique. 
McGraw-Hill Book Co., Inc., New York. 
Lamb, K. P. I960. A check list of New Zea- 
land plant galls (Zoocecidia) . Trans. Roy. 
Soc. N. Z. 88:121-139. 
Mani, M. S. 1964. Ecology of Plant Galls. Dr. j 
W. Junk, The Hague. ; 
Metcalfe, C. R., and L. Chalk. 1950. Anat- 
omy of the Dicotyledons, Vol. II. Oxford j 
University Press. 
