EXHIBITION MEETING, 1963 373 EXHIBITION MEETING, 1963 An Exhibition Meeting was held in t.he Department of Botany, British

About 350 members and guests attended and exhibits were arranged by 29 individuals. An account of these exhibits, based on notes supplied by exhibitors, is given below. AN ALISMA HYBRID Specimens were exhibited of a putative hybrid between ALisma Ianceolatum and A. plantago-aquatica from the Isle of Man. Herbarium material of the two parents was also shown for comparison.-D. E. ALLEN. VARIATION IN LIMONIUM The exhibit showed some of the variation in the two British salt-marsh species of Limonium, L. vulgare and L. humiIe. Population samples of I". vulgaTe from different marshes in the same area showed some of the forms that occur at different levels. The population from the higher and older parts of the marshes showed a very dense head of closely arranged spikelets. The lower populations showed a tendency towards the morph01o-gical character of L. humiIe, and some specimens appeared to be very close to that species. A few individuals of L. humiIe do grow with the common species in these areas. Between these extremes there was a complete range of forms. It would be easy to attribute these forms to environmental differences as they are each characteristic of a particular area. However, a comparison was made between flowering spikes collected from certain different forms in the wild, and those from the same indivi-duals raised under constant non-saline conditions in the experimental garden. This showed that while the habitat could influence to some extent overall size, the significant morphological character of an individual remained unchanged. It appears that the different forms typical of different levels in the salt marsh may be genetically determined.-L. A