S. Mahunka szerk.: Folia Entomologica Hungarica 43/1. (Budapest, 1982)

(KÁRÁSZ 1976). Large scale outbreak of Antispila treitschkeella larvae was observed in the leaves of Cornus mas. The larvae are monophagous and do not occur on the shrubs of Cornus sanguinea L. which is also very frequent in the forest. The larva prepares a two-sided, spot-shaped mine and before pupation gnaws itself out of it and falls to the ground between two oval-shaped interwoven epidermic discs (Fig. 1). The survey of the counts and changes was carried out by random sampling. We think that on examining altogether 2000-3000 leaves from 20-2 5 shrubs we could obtain objective data about the changes of the counts. In the measurements of matter circulation we used the following method: the live weight of the larvae just taken out of the mines was measured. Since the larvae had a rather small live weight'the dry weight was determined as the mean value for a few (15-20) individuals. The values obtained this way were used when calculating ecological capacities. In the estimation of consumption we followed the graphical integration method of NAKANO and MONSI (1968). First we determined the difference between the weight of 15 leaves and that of a piece of paper that had the same area. It is very important that the paper should have the same thickness everywhere! Later on we measured the weight of a piece of paper that corresponded to the size of the mine and then calculated the weight out of it. The rate of consumption is equal to the difference between this value and the weight of the epiderm measured back. In 1980 we determined the weights of the leaf and epidermic discs from the same leaf and so deduced the quantity of ground tissue. Later on calculations were carried out on the following basis: live weight: ground tissue (mg) = 0.70 x leaf (mg) - 0.025 (n = 81, r = 0.966) dry weight: ground tissue (mg) =0.51 x leaf (mg) - 0.06 (n = 74, r = 0.994). The quantity of faeces was also measured. In the calculations we supposed that this quantity shows no significant changes due to decay, shake-out or wash-out while it is in the mine. The timing of samples can be seen in Table 1. Table 1. Changes in the counts and biomass of Antispila treitschkeella in the years of 1977-1980 ind. leaf * ind. ha -1 kg ha 1 (live weight) kg ha 1 (dry weight) 1977. 09. 01. 0.99 5.587 X 10

6 1.674 0.598 09. 08. 1.85 10.441 X 10

G 2.610 0.932 09. 28. 1.92 10.836 X LO

6 6.956 1.855 1978. 08. 30. 0.07 0.399 X 10

6 0.039 0.007 09. 07. 3.22 18.195 X 10

6 2.151 0.615 10. 14. 1.99 11.231 X 10

6 6.240 1.664 1979. 09. 05. 1.17 6.611 X 10

6 1.322 0.626 09. 20. 6.09 34.412 X 10

6 17.206 4.646 1980. 09. 03. 0.40 2.246 X 10

6 0.049 0.202 09. 11. 1.45 8.155 X 10

6 4.078 1.060 09. 20. 2.71 15.318 X 10

6 10.723 1.900 Fig. 1. Mines of Antispila treitschkeella F.R. in the leaves of Cornus mas from the surface (a) and the inner parts of the shrubs (September, 1979) >