1 . This is a report on a preliminary investigation of the causes of insufficient fruit setting in the strawberry variety Jucunda, especially its clone JK3 2. From field experiments in different localities it was concluded :a . that raw weather increases the percentage of malformed fruits (nubbins) in Jucunda, especially in clone JK3, and b . that interplanting with a good pollen variety (Deutsch Evern) may decrease this percentage .3 . An insufficient pollination may take place in the centre of too closely planted beds . 4. Bees do not improve fruit setting in Jucunda . 5 . Usually the development of good anthers in Jucunda is not abundant, which means that the quantity of pollen produced is not large . 6 . The quality of the pollen, expressed as a percentage of morphologically good pollen, of the bad clone JK3 was sometimes a little lower than that of the good clones of Jucunda . 7 . Meiosis in the anthers of clone JK3 was normal . 8 . The fruit setting of the variety Deutsch Evern was good at all temperatures of the range of 10-26'C, whereas that of Jucunda was only good at 17-26"C . At 14 0 C and lower the fruit setting in Jucunda was reduced to zero . 9 . As the phenomena of this type of unfruitfulness are greatly influenced by the growth conditions of the plants, further investigation of this problem will be carried out under controlled conditions .

A study was made of the occurrence of apomixis and heterogamy in rose rootstocks belonging to the Canime. Of several 'Edelcanina'-selections progenies obtained from crossings with wild roses or from self-and open pollinations were analysed morphologically and cytologically. It was concluded that both apomixis and normal generative propagation occur. The presence of aneuploid plants is discussed, especially with reference to earlier investigations.

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