BRITISH BRYOLOGICAL SOCIETY
Survey of the
Bryophytes of Arable Land

Harold L.K. Whitehouse, who died in January 2000, dominated the study of bryophytes in Cambridgeshire throughout the second half of the 20th century. He came to Cambridge as an undergraduate in 1936 and participated in the first Cambridge Bryological Excursion in February 1938 (Richards & Whitehouse, 1988). After the departure from Cambridge of his mentor Paul Richards, he ran the excursions for exactly 50 years, from autumn 1949 to autumn 1999. He wrote for the first issue of Nature in Cambridgeshire (Whitehouse, 1958) and thereafter was author or coauthor of a series of reports on Cambridgeshire bryophyte records.

During this long period he achieved many things. From the very beginning, he compiled meticulous records and kept lists both for localities and sites. He also kept lists of people who attended excursions and correspondence about the excursions. (His correspondence file contains some nice ephemera such as a letter from Progressive Motor Coaches dated 2 February 1953, thanking him for his telephonic instructions and confirming that the bus to take the party to Hildersham would cost £2. lOs.) From his records he regularly prepared notes to be handed out when the party arrived in the field. Not only did the notes help beginners by listing the species that they could expect to see (helping, incidentally, with the fearsome spelling of many bryophyte names) but also they provided an incentive to the more expert to make additions and refind rarities. Each visit was a treasure hunt. Participants could compare their finds with those of predecessors, confident that any new records would be entered into the Whitehouse system and transmitted to posterity.

Repeated visits to 66 Cambridgeshire sites produced a record of change over the years. Among the most favoured places were the chalk-pits at Cherry Hinton, which were visited 14 times from 1950 to 1985. While chalk was still being extracted, pioneer mosses were abundant and included rarities such as Aloina brevirostris, A. rigida, Pterygoneurum lamellatum and P. ovatum, whose main distribution is in the world's semi-deserts. These species gradually disappeared. Harold himself made the last records of A. rigida and P. lamellatum in 1970. P. lamellatum has never again been seen in the British Isles and is thought to be extinct. Fortunately, one famous Cherry Hinton rarity, Tortula vahliana, grows in deep shade and has not been adversely affected by cessation of the workings.

Tortula vahliana was, in a small way, one of Harold's bryological 'pets'. He had a succession of these pets over the years, starting in the mid 1950s with the hitherto neglected mosses that produce rhizoid gemmae. He developed a highly successful technique for growing mosses in pure culture on agar and used it to demonstrate that many species grow in complex mixtures.He decided that rhizoid gemmae should be called tubers (Whitehouse, 1966). The name has stuck; a wag in the Low Countries has called those who study them potato-bryologists. Harold was definitely a potato-bryologist, but he also had many non-tuberous pets. T. vahliana produces protonema-gemmae, which makes it a member of a second group of favourites (Whitehouse, 1987). A few of these are mentioned in his bryophyte flora of the county (Whitehouse, 1964), but at that time he had done little work on them.

Many tuberous bryophytes are characteristic of disturbed ground and can be abundant on fallow arable land, In the the mid 1950s, when the potential of tubers as a means of distinguishing difficult sterile mosses became apparent, spring-sown crops were the norm. Stubble-fields were plentiful during autumn and winter and proved to be a rich hunting ground. Harold became fascinated by stubble-field mosses and found interesting assemblages in Cambridgeshire. Most of the county's tuberous mosses were first found here during the period 1956-60, both by him and by P.J. Bourne, who sent him clods from the fields. It is likely that these mosses have declined since that time, but the evidence is poor because farmers soon switched to winter cropping and the bryophyte flora of stubble-fields has not been sampled quantitatively.

Only one of Harold's pets was a flowering plant, Lythrum hyssopifolia (Preston & Whitehouse, 1986). Although not a bryophyte, it achieved merit in his eyes because it grew with bryophytes, especially Bryum klinggraeffii, in arable fields. Otherwise he restricted himself firmly to bryophytes. His favourite of all was the introduced tuberous moss Hennediella stanfordensis. He and David Coombe found it on the Lizard in 1958 (Whitehouse, 1961), and he searched diligently for it in many parts of lowland Britain. In 1977, he found it at Whittlesford, its first locality in south-east England. Dogged searches for particular species were very much his forte. In the last five years of the Cambridge Bryological Excursions, special expeditions were made to relatively remote locations with the specific aim of finding and studying mosses of interest. It seemed that, after 45 years, he was becoming less interested in Cambridgeshire.

Almost certainly this was because he had decided not to write another county flora. Other projects, such as his collaboration with Line Rochefort on the mosses of northern Canada, were getting priority. His main county flora (1964) was published only eight years after that of Michael Proctor (1956). In Harold's flora the notes on species were terse; many were little more than a general statement of habitat. (The notes by his co-authors on vascular plants were even shorter.) E.W. Jones (1965), in a review, regretted that there was not more ecological detail. In fact, the flora proved to be just what was needed to stimulate young bryologists in the county. It clearly set out the current state of knowledge and revealed many tantalising gaps. There was a surge of new recording. The next checklist (Crompton & Whitehouse, 1983) was full of interesting additional finds. The checklist was far more than a list of taxa. Not only did it enumerate the 10-km squares of each species, but it gave detailed and informative notes on newly recorded bryophytes, including the fascinating calcifuges that had appeared in Wicken Fen. After the checklist, Harold continued to maintain meticulous notes but with the intention that others should reap where he had sown.

Studies of the flora of Cambridgeshire were only a fraction of Harold Whitehouse's work on bryophytes (Hill & Preston, 1997). He was also a noted geneticist, university reader and loving husband and father. His wife Pat was a brilliant photographer, specialising in stereoscopic natural history photography (Walters, 1990). After her death, Harold used one of her specially constructed cameras to take stereo-photos of most of the British bryophyte flora.

He was a wonderful teacher, who transmitted his enthusiasm to the dozens of pupils on his Cambridge Bryological Excursions. He had a charming way of feigning interest when common plants were brought to him for identification. He would tilt his head to one side and say "I think this is Ceratodon purpureus", as if there was really some room for doubt, his manner even implying that the specimen was, in its way, quite notable. He and his listener were well aware that he knew it was common old Ceratodon, but never for a moment did he wish to imply that a beginner was silly or ignorant. On the contrary, his pupils were made to feel that they had found something valuable. Later, when they became friends and collaborators, he was invariably generous and encouraging.

Harold Whitehouse was energetic throughout his life. After retiring from his university post, he continued to work in the Department of Plant Sciences, occupying a space in the University Herbarium and keeping his agar cultures on the roof. He died suddenly at the age of 82, leaving a fine collection of bryophyte photos and a few projects at various stages of completion. Chris Preston and I, both of us his bryological pupils, are making preparations for a new county flora, which will take his longest-running project forward into the future.

References

Crompton, 0., & Whitehouse, H.L.K. (1983). A checklist of the flora of Cambridgeshire. Privately published, Cambridge.
Hill, M.O., & Preston, C.D. (1997). A birthday tribute: Dr H.L.K. Whitehouse. Journal of Bryology, 19: 387-389.
Jones, E.W. (1965). Book review: A Flora of Cambridgeshire. By F.H. Perring, P.D. Sell and S.M. Walters, with a section on Bryophyta (pp. 281-328) by H.L.K. Whitehouse. Transactions of the British Bryological Society, 4: 833-834.
Preston, C.D., & Whitehouse, H.L.K. (1986). The habitat of Lythrum hyssopifolia L. in Cambridgeshire, its only surviving English locality. Biological Conservation, 35: 41-62.
Proctor, M.C.F. (1956). A bryophyte flora of Cambridgeshire. Transactions of the British Bryological Society, 3:1-49.
Richards, P.W., & Whitehouse, H.L.K. (1988). Fifty years of the Cambridge Bryological Excursions. Nature in Cambridgeshire, No. 30: 41-49.
Walters, S.M. (1990). 'The Pat Whitehouse Show'. Nature in Cambridgeshire, No. 32: 76.
Whitehouse, H.L.K. (1958). Additions to the bryophyte flora of Cambridgeshire. Nature in Cambridgeshire, No. 1: 25-27.
Whitehouse, H.L.K. (1961). The occurrence of Tortula stanfordensis Steere in Cornwall, new to Europe. Transactions of the British Bryological Society, 4: 84-94.
Whitehouse, H.L.K. (1964). Bryophyta. In: A Flora of Cambridgeshire, by F.H. Perring, P.D. Sell, S.M. Walters & H.L.K. Whitehouse, 28 1-328. Cambridge University Press, Cambridge.
Whitehouse, H.L.K. (1966). The occurrence of tubers in European mosses. Transactions of the British Bryological Society, 5:103-116.
Whitehouse, H.L.K. (1987). Protonema-gemmae in European mosses. Symposia Biologica Hungarica, 35: 227-23 1.

Mark Hill

This obituary is reproduced with permission from 'Nature in Cambridgeshire', No. 42 (2000): 73-75. Current and past issues of this annual journal, to which Harold Whitehouse was a frequent contributor, are available from The Herbarium, Department of Plant Sciences, Downing Street, Cambridge, CB2 3EA (price £3.50 by post).