The third taxonomic workshop opened with a laboratory session on 20 November in the School of Biological Sciences, Thames Polytechnic, by kind permission of Mr M. D. Morisetti, Head of the School. The session was attended by 30 members and guests.
Mrs J. A. Paton started the day by discussing the identification of hepatics using sexual structures. Diagrams were drawn showing dioecious and various monoecious conditions, and the structure of antheridia and archegonia. Methods were described for finding these structures in specimens, and various problems mentioned. Fresh material was stated to be a great advantage in identifying hepatics. Mrs Paton gave a very useful list of genera and species of hepatics requiring fertile material for adequate identification. The ensuing laboratory work was based on material provided by Mrs Paton and gave several members the opportunity to examine antheridia and archegonia for the first time; and allowed all to consolidate the theoretical discussion with excellent practical examples.
Dr. J. G. Duckett talked about the genus Barbula in the afternoon, covering all but 3 of the 22 U.K. species. He pointed out first that one of the characters stressed by Dixon, the shape of the basal cells of the leaves, was not a good character, and then listed the characters he found most useful in distinguishing Barbulas. These characters were: leaf shape, excurrent nerve, elongated/short cells over the nerve. Within each group the species were distinguished by other key structural characters and habitat differences. The session continued with the examination of prepared microscope slides of all the species described. The slides, together with specimens from Dr. Duckett’s herbarium, were available to be taken away by interested members. Dr. Duckett also made available copies of the section on Barbula from Dr. Smith’s projected new moss flora, and copies of a checklist of British Mosses from Dr. Smith showing all the British taxa now recognized, including much updated nomenclature.
Members were very pleased to welcome Mr A. J. Pettifer to the afternoon session – unfortunately not now able to be a very frequent visitor to meetings. Another ex-President, the globe-trotting Mr Wallace, very kindly distributed duplicates from his herbarium.
On the second day of the weekend, ten members gathered on a cold but dry day at Gomshall Station, near Shere in Surrey. Whilst waiting for the train from London to arrive (it didn’t), speliologists in the party found Schistostega pennata in a sandstone cave by the railway track. The party continued up to the chalk of Hackhurst Downs where Dr. Duckett immediately found Barbula acuta new to Surrey. Other plants seen on the Downs included Aloina aloides, Barbula convoluta and var. commutata, B. hornschuchiana, B. fallax, B. unguiculata, Entodon concinnus, Fissidens incurvus, Thuidium hystricosum, Tortella inflexa, Weissia crispa and W. sterilis. Jean Paton was not in her element in such a predominantly mossy place, but producedLeiocolea badensis from a chalk pit.
After a rather late lunch, a quick inspection was made of an old wall in Shere where Barbula recurvirostra, B. rigidula, B. revoluta and B. trifaria were added to the list, but predominating was B. vinealis which was present in luxurious abundance. Orthotrichum anomalum and Grimmia pulvinata were also present. To provide a contrast, the party then moved on to the Lower Greensand at Pitch Hill, where Brachydontium trichodes and Polytrichum urnigerum c. spor. were seen. Further on towards Peaslake Bartramia pomiformis was frequent on a roadside bank, but steadily diminishing light and temperature forced an end to a day enjoyed by beginner and expert alike.
Many thanks must go to Mr Wallace for taking us to places that could provide such a wide range of interest, to Dr. Paddy Coker for being Local Secretary, laboratory technician and tea-boy, and to Mrs Paton and Dr. Duckett who did us proud both in the laboratory and in the field. We will all be looking forward to next November.
B. J. O’Shea