S. Mahunka szerk.: Folia Entomologica Hungarica 43/1. (Budapest, 1982)
Results and discussion 1. Seasonal and yearly changes in the counts and biomass From sampling 2-3 times in a year we can state that the hatching larvae in these three years began at the end of August and was finished in the middle of September (Table 1). The fact that the number of individuals per leaf has been very high refers to the extent of infection (1977: 1.9; 1978: 3.2; 1979: 6.1; 1980: 2.7 ind. leaf" 1 ). The number of individuals per ha was greater than 10 x 10®. In 1977-79 growth of counts could be observed. During this period the dry weight of the larvae was 1.66-4.65 kg ha 1 . An outstanding value was obtained in 1979, when the dry weight had reached 4.65 kg ha-1 . In 1980 both the number of individuals and the dry weight decreased, they were 15.32 x 10* ind. ha" 1 and 1.90 kg ha-1 • respectively. Table 2. Distribution of mines of Antispila treitschkeella in Cornus mas shrubs (individual x leaf ). Average values refer to all the investigated leaves 1978 Position of leaves Average diameter of the mines (mm) fallen down sum in the shrubs 2 4 6 8 9 12 fallen down total top 1.07 0.80 0.13 0.07 _ 0.03 2.10 upper-outer 1.58 1.63 0.30 0.11 0.03 0.02 0.03 3.70 upper-inner 0.75 2.25 0.25 0.08 3.33 lower-outer 0.74 1.09 0.34 0.09 0.09 0.02 2.36 lower—inner 0.47 0.94 0.35 0.12 0.12 2.00 average 1.16 1.36 0.29 0.09 0.04 0.01 0.03 2.98 1980 Position of leaves Average diameter of the mines (mm) fallen down sum in the shrubs 2 5 8 11 fallen down total upper-outer 3. 12 2.44 0.03 0.020 _ 5.33 upper-inner 0. 36 0.42 0.02 0.005 0.01 0.81 lower-outer 0. 27 0.44 0.02 0.005 0.75 lower-inner o. 13 0.15 0.002 0.27 average 0. 97 0.86 0.02 0.010 0.01 1.87 In 1978 and in 1980 we examined the distribution of mines in certain shrubs (Table 2). We found that on the "surface" of the shrubs there were more mines in the leaves than in the inner ones and the number of mines decreased downwards. This is verified in Fig. 1 where the damage observed in September 1979 can be seen on the surface (a) and in the inner parts (b) of the shrubs. 2. Matter circulation studies Researches in matter circulation were carried out in the years of 1977, 1979 and 1980 (Table 3). Maximal live weight of Antispila treitschkeella larvae was 1.1-1.3 mg ind.-1 , simultaneously the average weight of those larvae that fall down just before pupation was 0.7 mg. From the weight of the fallen larvae and from the comparison of their weight and the quantity of consumption and faeces we concluded that the larvae of Antispila treitschkeella, similarly to the larvae of other species, after reaching maximum weight, can lose part of it.
