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An archaeological excavation in the Tungelroyse Beek valley revealed the remains of two red deer specimens (Cervus elaphus) of Early Mesolithic age that possibly were the victims of hunter-gatherers. The find of animal remains of this age is unique in the Netherlands. In this respect, a sediment core taken close to the remains was investigated, i.e. to reconstruct the vegetation and landscape development of the site and to find more evidence for human activity at this site during the Early Mesolithic. The sediment core shows a typical Early Holocene palynological sequence from the Younger Dryas into the Middle Atlantic, which is supported by AMS dating. The microscopic charcoal record shows peaks in fire activity during the Younger Dryas and Friesland phase, probably wildfire related. Records of spores of coprophilous fungi indicate that the Tungeroyse Beek valley was a favourable place for large herbivores (game) to visit during the investigated period. However, around the age of the oldest red deer remains, no significant peak in fire activity or spores of coprophilous fungi is visible in the investigated record. The pollen diagram does not show disturbed or open vegetation around this age either. This study therefore suggests the impact of Early Mesolithic people on their environment was very low.

Since the discovery of pathotypes of the potato cyst nematode (Heterodera rostochiensis Wollenweber, 1923), surveys on the distribution of these pathotypes have been carried out in different European countries. Test varieties of potato were selected according to findings resulting in the present situation of varying distinctive host‐plants and of diverging programs for breeding potatoes resistant to the potato cyst nematode. With respect to rational selection and use of resistant potato varieties, there is a great need for standardization in pathotype identification (nomenclature), maintenance and supply of appropriate genotypes of Solanum species and methods for testing resistance in new potato varieties. Anticipating a cross‐experiment with pathotypes and test varieties from Great Britain, the Federal Republic of Germany and the Netherlands in 1974, a preliminary test with all recognized or presumed pathotypes from these countries, but with only part of the potential differential host‐plants was carried out by the Plant Protection Service at Wageningen. The results of this experiment are discussed.

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