7. .) pusilla (Lw.) July. Bayfield plain and by Lower Eastern pond. (Determined by J. E. Collin.) Empis ( Xanthempis ) punctata Mg. a female taken on 10 June, 1951. E. ( E .) rufiventris Mg. May, visiting flowers of Great Stitchwort, Stellaria holostea L. Hilara biseta Collin a female at Lower Eastern pond on 11 July, 1948 (determined by E. C. M. d’Assis Fonseca). H. thoracica Macq. a female found on 1 1 June, 1950. in Stents wood as the prey of the spider Dictyna unicinata Westr. (determined by our member G. H. Locket). Microphorus anomalus (Mg.) females taken on 12 June. 1949. and 11 June. 1950. Trichina clavipes Mg. female taken on 12 August, 1951. T. flavipes Mg. Oct., Central plain on the leaves of Salix sp. Dolichopodidae Achalcus cinereus (W alker) May, at Manor pond. Chrysotus angulicornis Kowarz a male taken on 12 Aug.. 1951 C. cilipes Mg. March, in Central wood. Medeterus saxatilis Collin July, on Bayfield plain. Porphyrops elegantula Mg. a temale taken on 12 June, 1941. Sciopus longulus (Fin.) June, on Central plain. Phortdae C. N. Colyer has kindly determined all my specimens of this family. Gymnophora arcuata (Mg.) collected on 11 July, 1954. Incorrect‘y mentioned in the 1950 paper p. 115 as G. acuta Mg. Megaselia aequalis (Wood) July, Bayfield plain. M. emarginata (Wood) June, Bayfield plain. M. flavicans Schmitz Nov., Hill House wood. M. gregaria (Wood) June, near the Isle of Wight pond. 72 THE LONDON NATURALIST, NO. 39 M. luteipes Schmitz Nov., at edge of Isle of Wight pond. M. manicata (Wood) April, at margin of Isle of Wight pond. M. pleuralis (Wood) July, Oct., Eastern Hollow and Eastern wood. M. ruficornis (Mg.) June, near the Isle of Wight pond. M. sinuata Schmitz Nov., Hill House wood. M. sulphuripes (Mg.) March, found in tufts of grass. Eastern plain. M. variana Schmitz June, in Central wood. M. verna Schmitz July, Bayfield plain. Phora aterrima (F.) June, Bayfield plain. Triphleba collini Schmitz March, in grass tufts, Bayfield plain. T. intempesta (Schmitz) Dec., Eastern plain. T. papillata (Wingate) March, Central wood, Hollow wood. CYCLORRHAPHA— ASCHIZA PlPUNCULIDAE R. L. Coe of the British Museum (Nat. Hist.) has kindly examined all my specimens of this family. Pipunculus campestris Latr. May, June, in Kelseys wood and Western Hollow. P.flavipes Mg. June, near the Isle of Wight pond. P. furcatus Egg. June, Kelseys wood. P. ultimus Beck. July, Stents Wood west. P. vittipes Zett. May, Hill House wood. Verrallia villosa (v. Ros.) May, Hill House wood. Platypezidae Platypeza infumata Harr, larvae found in the fungus Polystichus versicolor (L.) Fr. on 10 Dec., 1950, in Hollow wood. Flies emerged on 25 March to 22 April, 1951. Syrphidae Brachypalpus bimaculatus (Macq.) a female taken by P. W. E. Currie at the edge of Kelseys wood on 24 May, 1953. Cheilosia intonsa Lw. Aug., Central wood. C. paganus Mg. April, May, Sept., visiting flowers of Lesser Celandine, Ranunculus ficaria L. and of Burnet Saxifrage, Pimpinella saxifraga L., Central plain. Helophilus lineatus (F.) 15 Aug. 1953 — see report of field meeting Proc. S. London Ent. Nat. Hist. Soc., 1953-54: 89. Neoascia aenea (Mg.) Aug., at edge of Isle of Wight pond. Pipiza austriaca Mg. June, visiting flowers of hawthorn, Crataegus monogyna Jacq., Central plain. P. birnaculata Mg. May, on leaves of hazel, Corylus avel/ana L., Hill House wood. P. fenestrata Mg. May, visiting flowers of Creeping Buttercup, Ranunculus repens L., Bayfield plain. P. luteitarsis Zett. May, in Station Copse. Svrphus punctulatus Verr. April, Central wood. SCHIZOPHORA— ACALYPTERAE Otitidae Seioptera vibrans L. June, Bayfield plain. Pallopteridae Palloptera trimacula Mg. pupae found in the stems of Angelica sylvestris L. on 11 Dec., 1949. Flies emerged 20 April, to 6 May, 1950. L.P. 29 May, 1950, M. Niblett. A male was taken on Angelica sylvestris L. on 28 Aug., 1949, on Central plain by P. W. E. Currie. T RYPETIDAE Mr. Niblett’s intensive study, resulting in his paper “ The Distribution of Trypetidae (Diptera)” (Niblett, 1953), included four species additional to our original list published in 1950: — Acidia cognata (Wied.), Chaetostomella onotrophes (Lw.), Terrellia serratulae (L.) and Zonosema alternata (Fin.). Lonchaeidae Dasyops latiterebra (Czerny) June, Western Hollow. Earomyia nigra (Mg.) June, Eastern wood. E. virilis Collin a male taken on 18 May, 1941. Lonchea laticornis Mg. pupa found under bark; a male emerged on 19 April, 1949. Sapromyzidae Minettia inusta (Mg.) a female found as prey of the spider Dictyna uncinata Westr. (determined by G. H. Locket) on 11 June, 1950, in Stents wood. M. longipennis (F.) a male taken on 11 June, 1950. Psilidae Loxocera aristata (Panz.) June, Central plain, on leaves of wild parsnip, Pastinaca sativa L. Sepsidae Sepsis flavimana Mg. May, Hill House wood and Sept., visiting flowers of Burnet Saxifrage, Pimpinella saxifraga L., Isle of Wight plain. S. nigripes Mg. March, April, in grass tufts, in open clearing in Central wood and near Isle of Wight pond. S. violacea Mg. taken on 1 Sept., 1935. Themira nigricornis (Mg.) June, Bayfield plain. Chamaemyiidae Leucopis annulipes Zett. June, Bayfield plain. Helomyzidae Allophyla atricornis (Mg.) Sept., on the leaves of Sycamore Acer pseudoplatanus L. in Hill House wood. Helomvza pallida Fin. Oct., South Eastern wood. THE SURVEY OF BOOKHAM COMMON 73 Chyromyidae Chyromya flava (L.) bred by S. Wakely from a nest of the wasp, Vespula germanica (F.). Flies emerged 19 to 21 May, 1952. Clusiidae Clusiodes albimana (Mg.) May, about fallen tree trunk , Hill House wood. Anthomyzidae Anthomyza gracilis Fin. July, in long grass, near Isle of Wight pond. Ephydridae Hyadina guttata (Fin.) March. April, May, in grass tufts at Eastern plain. Eastern Hollow and the margin of the Isle of Wight pond. Hydropota cardamines (Hal.) Aug., in Juncus at the margin of the Isle of Wight pond. H. thoracica (Hal.) Aug., in Juncus at edge of the Isle of Wight pond. Limnellia quadrata Fin. Nov., South Eastern wood. Sphaeroceridae Borborus ater Mg. March, Central plain and Central wood. Collinellula cryptochaeta (Duda) Jan. to May, found on a dead Blackbird and in grass tufts. Eastern plain, edge of Isle of Wight pond and Western Hollow. C. palustris (Collin) March. April, on fresh horse dung, in Juncus clump, edge of Upper Eastern pond, Western plain and Isle of Wight marsh. Coprophilo ferruginata (Stenh.) Nov., on dead mole, Central plain. Litnosina silvctica (Mg.) Jan., on horse dung. Central plain. Sphaerocera paracrenata Duda, Feb., in grass tufts. Eastern plain. Asteidae Leiomyza laevigata (Mg.) June. Bayfield plain. Drosophilidae Our member E. B. Basden has kindly examined all my specimens. Drosophila forcipata Collin Nov., South Eastern wood. D. kuntzei Duda Oct., Bayfield plain. D. melanogaster Mg. Aug., Oct., visiting flowers of Large Bindweed. Calystegia septum (L.) Roem. & Schult and flowers of Ivy, Hedera helix L. and fresh Stinkhom fungus. Phallus impudicus Pers., Central and South Eastern woods. D. subobscura Collin Feb., June, on sodden bread. Eastern plain, also on Bayfield plain. Scatomyza griseola (Zett.) March, Central wood. Agromyzidae My collection of these flies and their mines have been examined by Dr. E. M. Hering of Berlin, to whom my grateful thanks are tendered. Agromyza alnibetulae Hd. larvae found in June to Sept., mining leaves of Birch. Bctuia nendula Roth. A. cinerascens Macq. captured by C. N. Colyer on 11 April, 1948. A. dipsaci Hd. larvae found in July mining the leaves of Teasel, Dipsacus fullonum L. A. ( Domomyza ) mobilis Mg. June, Sept., Oct., South Eastern w'ood, found in a spider’s web. A. nana Mg. larvae in June to Oct., found mining the leaves of White Clover, Trifolium repens L. and Red Clover T. protense L. A. nigripes Mg. captured 14 May, 1942, in a clump of Juncus growing in the ditch of Isle of Wight plain. A nigrociliato Hd. captured on 25 May, 1953. A. reptans Fin. adult flies captured in Sept, in Central wood on the leaves of nettles, L rtica dioica L. in which larvae mine June to Nov. Liriomyza amoena (Mg.) larvae found in June to Oct. in the leaves of Elder, Sambucus nigra L. L. flaveola (Fin.) captured on 25 May, 1953, and 10 July. 1949, also larvae in mines found in June to Oct., in blades of the grass Yorkshire Fog, Holcus lanatus L. i. sonchi Hd. larvae found in August, mining the leaves of Corn Sow'thistle, Sonchus arvensis L. L. strigata (Mg.) larvae found in June to August mining leaves of Corn Sowthistle, Sonchus arvensis L. and Knapweed, Centaurea nigra L. L. taraxaci Hg. larvae found in June to August, mining leaves of Dandelion, Taraxacum officinale Weber. L. trifolii (Burgess) larvae found in July to Sept., mining leaves of Meadow Vetchling Lathyrus pratensis L., and Tufted Vetch, Vicia cracca L. Melanagromyza aeneiventris (Fin.) reared in June. 1951. from pupae found in the stems of Angelica sylvestris L. on 6 May, 1951 (M. Niblett, 1952). M. lappae (Lw.) a male captured on Central plain on 8 June, 1952. Flies reared on 3 June, 1950. from pupae found in the cambium of stems of Hogweed, Heracleum sphondylium L. M. nibletti Spencer reared from Pepper Saxifrage, Silaum silaus (L.) Schinz & Thell. Holotype 6 Aug., 1951, paratypes 6 and 8 July, 1951 (M. Niblett) and 3 April. 1957 (K. A. Spencer). K. A. Spencer in Proc. R. ent. Soc. Lond. (B.) 26: 180. M. pulicaria (Mg.) larvae found in May. mining leaves of Dandelion, Taraxacum officinale Weber. M. sativae Spencer Paratypes reared May, June, 1956, from stem of Wild Parsnip, Pastinaca sativa L.. K. A. Spencer Proc. R. ent. Soc. Lond. (B.) 26: 181-2. M. torilidis Spencer Holotype and paratypes reared from pupae from stems of Upright Hedge Parsley, Torilis japonica (Houtt.) DC. flies emerging 17-24 Mav, 1956, K. A. Spencer Proc R. ent. Soc. Lond. (B.) 26: 182. Napomyza glechotna (Kalt.) flies taken on 6 May, 1951, about Ground Ivy, Glechoma hederacea L. Larvae found mining leaves April to Nov. N. lonicerellu Hd. larvae found in June to Nov., mining the leaves of Honeysuckle, Lonicera periclymenum L. N. xylostei (Kalt.) a male reared May, 1949, from a mine in leaf of Honeysuckle, Lonicera peri¬ clymenum L. found on 14 November, 1948. Larvae found June to Aug. as well. 74 THE LONDON NATURALIST, NO. 39 Ophiomvia heracleivora Spencer Holotype reared 8 Feb.. 1957, from puparia collected 17 Sept., 1956, in the base of rotting leaves of Hogweed, Heracleum sphondylium L., K. A. Spencer Proc. R. ent. Soc. Lond. (B.) 26: 112-3. O. proboscidea Str. a female captured on 25 May 1941. O. senecionina Hg. reared from stems of Senecio sp. by M. Niblett, K. A. Spencer Ent. Gazette, 8, 26 Phytagromyza hendeliana Hg. larvae found in May to Oct., mining the leaves of Honeysuckle, Lonicera periclymenum L. P. lonicerae (R.D.) a male captured 23 March, 1951; larvae found in May and June mining the leaves of Honeysuckle, Lonicera periclymenum L. P. tremulae Hg. larvae in August, mining the leaves of Aspen, Populus tremula L. Phytobia ( Poemyzc ) atra (Mg.) June, Central plain. P. (Trilobomyza) labiatarum (Hd.) larvae in June to Oct., mining the leaves of Hedge Woundwort, Stachys sylvatica L. P. ( Dizygomyza ) luctuosa (Mg.) a male captured on 1 Sept., 1935, and one on 14 May, 1942, in an area of Juncus on Isle of Wight plain. P. ( Poemvza ) pygmaea (Mg.) larvae found in July and August, mining the leaves of Oatgrass, Arrhenatherum elatius (L.) Beauv. est J. & L. Presl. P. (Poem.) pygmella (Hg.) captured on 10 June, 1951. P. (Poem.) semiposticata (Hd.) captured on 1 Sept., 1935. Phytomyza affinis Fin. July found near Isle of Wight pond and resting on bracken on Central plain. Found mining the leaves of Centaurea nigra L. May, 1954, parasite reared 11 June, 1954, Rhizarcha nitetis Nixon (Hym. Braconidae) G. C. D. Griffiths, Ent. tnon. Mag., 92: 27. Also larvae found in July to Oct., mining leaves of Cirsium arvense (L.) Scop. P. albipennis Fin. a female captured on 12 June, 1949. P. angelicae Kalt. mines in leaves of Angelica sylvestris L., flies reared 20 to 26 April, 1952. Larvae found in May, August and September. P. angelicastri Hg. larvae found in July to September, mining leaves of Angelica sylvestris L. P. anthrisci Hd. larvae found in May, August, September, November, mining the leaves of Keck, Anthriscus sylvestris (L.) Hoffm. near Lower Eastern pond and as early as 14 Jan. A female captured in South Eastern wood on 12 Dec., 1948. P. atricornis Mg. larvae found mining Fleabane, Pulicaria dysenterica (L.) Bernh., Hoary Ragwort, Senecio erucifolius L., Bur-Marigold Bidens tripartita L. Also found mining the leaves of a “ Cineria ” Senecio cruentus DC. at Bayfield Hotel. Larvae found March to December. P. chaerophvlli Kalt. larvae found in June and July, mining the leaves of Chaerophyllum temulentuns L. P. conii Hg. larvae found in June, in mines in leaves of Hemlock, Conium maculatum L. P. conyzae Hd. larvae found in June to Oct. in mines in Fleabane, Pulicaria dysenterica (L.) Bernh. P. lappina Gour. larvae found in June to Oct., mining the leaves of Great Burdock, Arctium lappa L. P. leucanthemi Hg. empty mines found in Ox-eye daisy, Chrysanthemum leucanthemum L. on 3 July, 1955 — Field Meeting report Proc. S. Lond. ent. nat. Hist. Soc., 1955: 77. P. melana Hd. larvae found in June, August to October, mining the leaves of Burnet Saxifrage, Pimpinella saxifraga L. P. milii Kalt. captured in March and April, in grass tufts and long grass about Sheepbell pond, at Kelseys Clearing and on Eastern plain. P. notata Mg. empty mines found in the leaves of Creeping Buttercup, Ranunculus repens L. P. obscurella Fin. larvae found in June to August and October, mining the leaves of Goutweed. Aegopodium podagraria L. P. pastinacae Hd. mines found in July to November, mining in the leaves of Wild Parsnip, Pastinaca sativa L., flies reared in May, 1953. P. periclymeni de Meij. mines found in the leaves of Honeysuckle, Lonicera periclymenum L. 3 July, 1955 — Field Meeting Report. Proc. S. Lond. ent. nat. Hiwt. Soc., 1955: 77. P. primulae R.D. larvae found in June to September, mining the leaves of Primrose, Primula vulgaris Huds. P. pubicornis Hd. larvae found in May, mining the leaves of Goutweed, Aegopodium podagraria L. P. ramosa Hd. larvae found in July, mining the leaves of Teasel, Dipsacus fullonum L. P. silai Hg. mines found in August in the leaves of Pepper Saxifrage, Silaum silaus (L.) Schinz & Thell. G. C. D. Griffiths reared its parasite Priapsis dice Nixon (Hym, Braconidae), Ent. mon. Mag., 92: 28. P. spondylii R.D. larvae found in mines of leaves of Hogweed, Heracleum sphondylium L. reared Sept., 1952. Larvae found June to August and in October. Milichiidae Phyllomyza securicornis Fin. a male captured on 14 May, 1950, under the oak tree at the lunch place by the Isle of Wight pond. Chloropidae Chlorops serena Lw. captured on 10 June, 1951, and identified by J. E. Collin. Dicraeus vallaris Collin a male captured on 12 June, 1948, along the Central plain ditch. Elachiptera brevipennis (Mg.) March, April, in grass tufts on Bajfield plain and at margin of Isle of Wight pond. Oscinisoma cognat a (Mg.) captured on 8 April, 1951, in grass tufts at the margin of the Isle of Wight pond and identified by J. E. Collin. Tricimba lineella (Fin.) Duda June, Bayfield plain. Tachinidae Blepharomyia amplicornis (Zett.) a male captured in Central wood on 14 May, 1950. Brachicheta strigata (Mg.) a female found on the trunk of an oak tree, Central wood on 27 March, 1948. Dexia rustica (F.) a male captured on 11 Sept., 1949. Exorista simulium (Mg.) a male captured on 10 July, 1949. THE SURVEY OF BOOKHAM COMMON 75 Ocyptera interrupta Mg. a male found on bracken, near Bank’s Cottage on 29 June, 1947 by P. W. E. Currie. Phebellia glauca (Mg.) a female captured on 11 July, 1948, in Stents wood. Servillia lurida (F.) May, Hill House wood and Western plain. Zenillia insiduosa R.D. = roseanae B. & B. reared 10 July, 1952, from Large Marbled Tortrix, Sarrothripus revayana Scop. (Lep., Hylophilidae) by S. Wakely. Calliphoridae Blaesoxipha laticornis (Mg.) a female taken on Eastern plain on 8 July, 1947. W. Ruttledge reared a specimen, identified by Dr. F. van Emden, from the grasshopper Chorthippus parallelus (Zett.) on 21 June, 1951. Macronichia polydon (Mg.) reared on 2 April, 1950, from the nest of Clytochrysus cavifrons (Thoms.) (Hym, Sphecidae), found on Eastern plain. Melinda caerulea (Mg.) this was incorrectly printed as Melina caerula in the original list of 1950. Onesia aculeata (Pand.) male taken on 17 May, 1942. in Kelseys wood. Pachyophthalmus signatus (Mg.) a male captured on the 14 May, 1950, in Central wood. Sarcophaga haemorrhoa Mg. June, Bayfield plain. 5. nigriventris Mg. July, Eastern plain. Muscidae My friend E. C. M. d’Assis Fonseca has helped greatly in the identification of the specimens of this family. Achanthiptera inanis (Fin.) reared on 1 June, 1952, from a nest of the wasp, Vespula germanica (F.) by S. Wakely. Acroptena ambigua (Fin.) August, margin of Isle of Wight pond. Botanophila varicolor (Mg.) a female taken on 9 June, 1935. Caricea intermedia (Fin.) July, Eastern plain and Lower Eastern pond. C. tigrina (F.) August, in marsh by the Isle of Wight pond. Che'isia monilis (Mg.) July, Sept., in long grass — Eastern Hollow and near the Isle of Wight pond. Chirosia setifemur (Ringd.) taken on 10 June, 1951, on bracken. Coenosia distinguens Collin August, in marsh by the Isle of Wight pond. C. lineatipes (Zett.) June to Oct., Bayfield and Eastern plains. Lower Eastern pond. C. infantula Rond. Sept., on bracken, on Glade path. C. pulicaria (Zett.) July, Central plain. Craspedochaeta pullula (Zett.) April, August, swept from reeds and sedges. Delia cepetorum (Mde.) May, Hill House and Stents woods. D. cilcrura (Rond.) April and July, by the Isle of Wight pond and on Eastern plain, visiting flower of Large Bindweed, Calystegia sepium (L.) R.Br. D. exigua (Mde.) May, Bayfield plain and Stents wood. D. intersecta (Mg.) March, April, resting on path, on leaves of oaks and hollies along the paths in Central, Kelseys and Stents woods. Fannia aerea (Mg.) August, female visiting flower of Wild Parsnip, Pastinaca sativa L., Central plain. F. pallitibia (Rond.) Sept., females found resting on leaves of Sycamore tree. Hill House wood. F. polychaeta (Stein) August, Central wood. F. serena (Fin.) May, June, Western wood. F. similis (Stein) a male captured on 15 June, 1938. F. vesparia (Mde.) eight males and three females reared between 22 and 28 May, 1953, from a nest of the wasp, Vespula germanica (F.) by S. Wakely. He’oecnema affinis Mall. May, June, Oct. Western plain and on vegetation of the Isle of Wight ditch. Helina allotalla (Mg.) August, in an aera of Juncus at the margin of the Isle of Wight pond. H. depuncta (Fin.) sucking blackberries on Central plain in Sept., but found resting on leaves of oak trees and on bracken in Oct. in Central and South Eastern woods. H. marmorata (Zett.) a male taken on 12 June, 1941. H. obscurata (Mg.) July, Lower Eastern pond. Hydrotaea militaris (Mg.) June, Eastern wood. H. occulta (Mg.) the males cruise up and down under oak trees at the lunch place by the Isle of Wight pond in May. A female was found on a dead Rabbit on 14 May, 1942. Hylephila per sonata Collin A male taken by A. E. le Gros on 23 May, 1953. Lispocephala alma (Mg.) a female found in long grass by South Eastern pond on 27 April, 1947. Mydaea scutellaris R.D. July, Eastern wood. Nupedia dissecta (Mg.) April, May, August, visiting flowers of Creeping Buttercup, Ranunculus repens L. and of Wild Parsnip, Pastinaca sativa L. in Western Hollow and Central plain. N. latipalpis (Lw.) Collin May, Station copse. Oplogaster mollicula (Fin.) July, Eastern wood. Paregle aestiva (Mg.) visiting the flowers of Creeping Buttercup, Ranunculus repens L. in May. Pegohylemyia fugax (Mg.) May, July, Sept., about the ponds from Isle of Wight to Upper Eastern pond. Pegomya dentiens Pand. from pupae found in stems of Meadow-sweet, Filipendula ulmaria (L.) Maxim, in Oct., flies were reared by M. Niblett in the following April. P. flavipes (Fin.) Aug., Central wood. P. haemorrhoa (Zett.) found on leaves of hazel, on 14 May, 1942, Sheepbell wood. P. hyoscyami (Panz.) empty mines found in leaves of Bittersweet, Solanum dulcamara L. were attributed to this species by Dr. E. M. Hering. form biol. chenopodii (Rond.) larvae mining the leaves of Allseed, Chenopodium polyspernum L. 9 August, 1953, identified by Dr. E. M. Hering. P. seitenstettensis (Strobl) larvae found mining the leaves of Wood Sorrel, Oxalis acetosella L. by G. C. D. Griffiths on 3 July, 1955 [Recorded as P. steini Hend. in error in Proc. S. Lond. ent. nat. Hist. Soc., 1955: 77, confirmed G. C. D. Griffiths.] P. ulmaria (Rond.) July and Sept, visiting flowers of Ranunculus repens L. P. univittata (V.Ros.) Sept., resting on the leaves of Sycamore, tree, Hill House wood. Phaonia fuscata (Fin.) April, May, resting on tree trunks. 76 THE LONDON NATURALIST, NO. 39 Phorbia genitalis (Schnab.) a male taken on a leaf of oak tree by the path in Kelseys wood, on 9 April, 1946. P. unipila (Karl) Sept., Central wood. Pseudocoenosia longicauda (Zett.) August, in marsh by the Isle of Wight pond. Stomoxys calcitrans (L.) August, margin of Isle of Wight pond. REFERENCES ON BOOKHAM CARRINGTON, L. L, el ah, 1944, Some Preliminary Notes on the Birds of Bookham Common. Lond. Nat. for 1943, 23-29. JONES, A. W., 1954, The Flora of Bookham Common. Lond. Nat., 33, 25-47. NIBLETT, M„ 1951, Plant Galls in Surrey, 1950. Lond. Nat., 30, 11-13. - , 1952, Notes on some Diptera of Bookham Common, 1951. Lond. Nat., 31, 47-49. - , 1953, The Distribution of Trypetidae (Diptera). Lond. Nat., 32, 48-51. - , 1956, The Flies of the London Area: III, Trypetidae. Lond. Nat., 35, 82-88. - , 1957, The Gall Midges (Cecidomyiidae) of Bookham Common. Lond. Nat., 36, 51-54. NYE, E. R., 1955, The Flies of the London Area: II, Culicidae, Sub-Family Culicinae (Mosquitoes ) Lond. Nat., 34, 114-126. PARMENTER, L., 1952, The Flies of the London Area: I, Conopidae. Lond. Nat., 31, 25-29. - ~, 1950, The Diptera of Bookham Common. Lond. Nat., 29, 98-133. OTHER REFERENCES ELTON, C., 1933, The Ecology of Animals. London. MILES, P. M., 1952, The Entomology of Bird Pellets. Amat. Ent. Soc. Leaflet, 24, 1-8. OWEN, D. F., 1956, The food of nestling Jays and Magpies. Bird Study, 3, 257—265. PARMENTER, L., 1958, Flies (Diptera) and their Relations with Plants. Lond. Nat., 37, 115-125. - , and OWEN, D. F., 1954, The Swift. Apus apus L., as a predator of flies. J. Soc. Brit. Ent., 5, 27-33. WTTHERBY, H. F., et a/.. 1938, The Handbook of British Birds. London. The Aquatic and Wasteland Plants of Bookham Common By A. W. Jones In the years 1951 to 1956 surveys were made of the Ponds and Hollows, the streams, the site of a water pipeline, and waste places generally. It became apparent whilst making these seemingly unconnected surveys that the flora of the different habitats often had much in common and this paper attempts to show the dual nature of many of the plants involved. First, however, we will deal with the four individual surveys. Ponds and Hollows These were surveyed in 1951 and 1952 and may be grouped thus: — 1. The Hollows Valley including three major ponds and two hollows. 2. Sheepbell Pond. 3. Minor Ponds. The Hollows Valley The Ordnance Survey 1 inch map of 1887 shows five ponds in this valley and they are now represented (from east to west) by U.E. Pond, L.E. Pond, East Hollow, West Hollow and I.o.W. Pond (see sketch map on page 78). They have many points in common and are therefore treated here as a group. The whole valley is bordered with woods except for a small area on the south border of the east end of E. Hollow. The fall from the head of Greendell Ditch (to the immediate east of U.E. Pond) to I.o.W. Pond is 25 feet. The five units are now considered in detail, followed by suggestions as to the succession that probably took place. 1. I.o.W. Pond In the west Sparganium erectum stretched a little way along the north and south sides, almost enclosing a large area of Equisetum fluviatile THE SURVEY OF BOOKHAM COMMON 77 which was bounded on the east by a thick growth of Typha latifolia. The area thus described is the pond as shown on modern maps, and the north-east and south-east edges were bordered by Salix cinerea. Although the area was completely dry in 1952 it did not dry up in the six vears following. Further to the east were two extensive areas of Salix cinerea , one in the north and another in the south, followed by yet another line of scattered bushes as far as the west dam of West Hollow. East of the Typha latifolia was a mixture of Sparganium erection , Equisetum fluviatile and Galium palustre , which does not fit in at all well with the general pattern of the pond. This was followed by a marshy area with a local dominance of Ranunculus repens and Juncus effusus , which gave way to a very mixed vegetation in the extreme east. The pond could thus be divided into the pond proper, and a marsh to the east. A small square pit dug in December, 1948, in the south-west corner, lor clay to reinforce the dam, supported a shallow open-water community of Potamogeton natans. Ranunculus aquatilis, Apium inundatum , etc. 2. L.E. Pond The dam here was repaired shortly after the Second World War. Sparganium erectum dominates the west and Equisetum fluviatile the east with a border of mixed marsh vegetation including only a little Epilobium hirsutum. The north and south and to a lesser extent, the east are bordered with Salix cinerea. 3. U.E. Pond This was the most permanent pond in the valley, retaining some water even in the dry summer of 1952. Sparganium erectum was found only in the north-west and south-west comers, Equisetum fluviatile occupying the west half and Epilobium hirsutum the east half, of the rest of the pond, with a border of Salix cinerea in the north-east, east and south. 4. West Hollow Epilobium hirsutum was more or less dominant here with a mixed marsh vegetation. Salix cinerea bordered the north, east, and south but did not occur in the central portion. In the summer of 1954 it was cut down along the north edge together with part of the wood behind but the Salix cinerea merely suckered from the old stools. 5. East Hollow The west half was very wet (but less so than West Hollow) and a mixed vegetation occurred with Epilobium hirsutum only scattered; Salix cinerea only bordered the south and north and slightly at the east end, not occur¬ ring in the central portion. The east half, which was marshy along the stream, was largely domi¬ nated by Deschampsia cespitosa with characteristic associated flora. Salix cinerea was absent from the borders of this half, occurring only in the marshy area. 6. Succession It would appear that in 1887 there were five ponds in this valley but since then the ponds have become progressively more overgrown and silted up and two of the dams are permanently broken. The succession that 78 THE LONDON NATURALIST, NO. 39 0001 _ oos THE SURVEY OF BOOK HAM COMMON 79 has followed in the last 70 years has not been recorded but, as the vege¬ tation of each of the ponds is perhaps at a different stage, some inferences of their evolution can be drawn. It has been suggested that these ponds are quite ancient, being originally formed by the damming up of the valley at five points for fish ponds. Harvey (1943) says one existed as a fish pond in 1816. In each of the ponds the deeper end would have been by the dam which would also be the wider, the eastern end being very shallow and narrower. As the fall over the ponds is 25 feet and there would have been five dams, each would have been approximately 5 feet high to put the whole valley under water. Marsh vegetation would develop rapidly at the east ends of the ponds where the water would be very shallow and this would collect silt. A reduction in the amount of water in the ponds could arise from : _ (a) Dry summers. (b) Breaking of the dam. (c) Changes in drainage— Greendell Ditch now continues no further back than the edge of the Common where there is a very small garden pond; it appears that there was once further drainage into it from the east but building may have affected this. The chief drainage is presumably from the northern woods of the Common although the ditches from the woods are more or less derelict and now rarely contain water. S.E. Ditch is now permanently dry. (d) Silting up and general growth of vegetation raising the beds of the ponds (though this would not necessarily affect the water level). Plants of open water would probably be the first to appear in the ponds and may have been introduced. Potamogeton spp., Myriophyllum alterni- florum, Ranunculus aquatilis and Elodea canadensis are amongst those recorded in recent years. Marshland plants developing at the eastern ends would tend to advance westwards as the pond silted up and their place taken by plants requiring dryer habitats. If the assumption of an encroachment of marsh vegeta¬ tion from the east is feasible, the present westerly flora will have been the first to arrive in the ponds and so on. The zonation of such species as are dominant in parts of each of the ponds from west to east seems to be: _ (a) Sparganium erection (b) Equisetum fluviatile (c) Epilobium hirsutum (d) Mixed. (e) Deschampsia cespitosa (if E. Hollow at the east end was ever under water). Another feature is the growth of Salix cinerea at the edge of the water line where it germinates on the bare mud. The whole valley is bordered with woods except for a small area on the south border of the east end of E. Hollow. Many other ponds on the Common are bordered by woods and some are deeply shaded but in none was there any marked invasion by woodland plants. Usually an encroachment of two or three yards was the limit and presumably the areas were still extremely wet with the water level only just below the ground. In the I.o.W. Pond there were a number of lines of Salix cinerea presumably representing various old limits of the pond. They do not. however necessarily indicate continuous falls in the water level as they could well be formed after an increase of surface water. In the years following the survey the clump of Typha latifolia increased and the species started 8o THE LONDON NATURALIST, NO. 39 to colonize an area in the middle of the west side, ousting the Sparganium erectum. Selby (1955) points out that in the Epping Forest Ponds the rhizome of Typha latifolia grows within an inch of the surface of the mud and is 1-li inches thick and easily ousts the thinner rhizomes of Sparganium erectum which also occur near the surface. When the dam was repaired shortly after the Second World War, L.E. Pond would have had the greatest water surface for many years. This appears to have encouraged the growth of Sparganium erectum which was only locally dominant in 1944 when the centre of the pond was covered by Equisetum fluviatile surrounded by a mixed marsh vegetation (including Sparganium erectum). As will be seen these two plants had by 1952 occupied three-quarters of the pond between them. In U.E. Pond the only noteworthy change in recent years was that Equisetum fluviatile appeared to have encroached as far as the west edge since 1944. The broken dam of West Hollow resulted in the absence of any per¬ manent standing water. Probably the water drained out within a short time of the break as the Salix cinerea is confined to the borders and does not occur in the central parts as would have been the case had there been several widely separated falls in the level of the former pond. Equisetum fluviatile has disappeared from W. Hollow although Sparganium erectum still occurs. It would thus appear that, although Sparganium erectum is pushed out by Equisetum fluviatile on a slowly falling water level, complete drainage eliminates Equisetum fluviatile first. The west half of East Hollow was bordered by Salix cinerea but the bushes did not occur in its central portion so probably the water drained out in a short time after the dam was broken, as in West Hollow. Like¬ wise there was a little Sparganium erectum left but no Equisetum fluviatile. The absence of Salix cinerea from the borders of the east half of East Hollow suggests that the area was never permanently under water. It is strange that this half dominated by Deschampsia cespitosa adjoins the Molinia caerulea area of E. Plain, the latter plant being sparse in E. Hollow. Sheepbell Pond This was deeply shaded and had few interesting plants in it; never¬ theless it was the most permanent of the ponds, the water level appearing to be constant at all times of the year. The pond was normally covered with Lemna polyrhiza and L. minor but in the winter of 1953/54 it was noticed that the liverwort Riccia “ fluitans ” agg. had achieved a sudden dominance. Since then Riccia has remained dominant in the winter and co-dominant with the two Lemnas in the summer. No records of Riccia “ fluitans ” agg. prior to 1953 are known for the Common but it was recorded for Crater 264 in April, 1956, Lower Eastern Pond in Nov., 1957, and Bayfield Pond in May, 1959. Minor Ponds These are: — 1. Bayfield Pond. This pond was very shallow with no surface water for long periods in most summers. A marsh vegetation occurred in the south-east but the other half of the pond was rather barren al¬ though Ranunculus aquatilis, Potamogeton natans and Callitriche sp. each covered a fair area in their respective seasons. It is shaded by a number of old Salix fragilis, four probably being 100 years old. THE SURVEY OF BOQKHAM COMMON 8l 2. S.E. Pond. This pond is dry in most summers and shaded by trees on all sides. The vegetation had changed remarkably since 1944, Agrostis canina becoming dominant along the N.W., W. and S. edges and Solatium dulcamara , a striking feature in the autumn of 1944, was no longer frequent. A number of Salix cinerea bushes formed a rough circle at some dis¬ tance from, and within the edges of, the pond. Inside this, Sparganium erectum remained dominant and also occurred outside the circle to the north and east, this being a very different habitat from that in Hollow Valley. Equisetum fluviatile was not present. 3. Kelseys Pond. Shaded by trees on three sides, this pond was used by cattle which approached it from the north. It dried up completely in most if not all summers and had little vegetation, although when the pond is dry Callitriche sp. was fairly extensive on the mud. It does not appear to have changed since 1944. 4. Manor Pond. This had Bookham Stream running through it and was consequently always very marshy but had little claim to be a pond. Sparganium erectum , Epilobium hirsutum and Mentha aquatica are co-dominant. 5. W. Pond. This was only a marsh occurring further down Bookham Stream (and slightly to one side of it). 6. Banks Pond. Still further down Bookham Stream it had become almost merged into the general vegetation of the plain and its only distinction was the occurrence of Oenanthe fistulosa w'hich is found nowhere else on the Common. 7. Little I.o.W. Pond (Map reference 5712). This is very small (a few yards long), was shaded by a large Salix cinerea and dried up very quickly in the summer. It supported Symphytum officinale and S. peregrinum. 8. Three Mark Oak Ponds. These are all very small and deeply shaded and the principal plants were Juncus effusus and Solanum dulcamara. 9. Four Bomb-Craters (Map references 264, 544, 736 and 766). The first three contained permanent water despite their small size. Crater 264 was the only locality for Scirpus fluitans on the Common. The chief vegetation of Crater 544 was a colony of Typha latifolia and of Crater 736, Sparganium enter sum and Eleocharis palustris. These crater ponds have been dealt with by Castell (1955). The flooded Gun-Pits on Eastern Plain have not been included in this paper, the vegetation having been dealt with by Baneerter and Castell (1949 and 1951). Streams In 1955 a survey was made of the chief streams, each of which was divided up into divisions of approximately equal length: Bookham Stream into 6, Banks Stream 2, I.o.W. Ditch 3, and Central Ditch 4, a total of 15 divisions. It soon became obvious that most of the plants occurring along the banks were not aquatics. Their presence was chiefly due to the wasteland habitat created by mud being thrown on the banks when the ditches were 'cleared. Epilobium hirsutum often dominated a border for some yards on either side of many parts of the streams, often spreading into the stream itself, with Calystegia sepium twining over it. Urtica dioica was often abundant along the banks. Conium maculatum was locally 82 THE LONDON NATURALIST, NO. 39 abundant along I.o.W. Ditch and Bookham Stream, occasional along Banks Stream, but appeared absent from Central Ditch. The vegetation of the stream beds was very sparse indeed. Epilobium hirsutum often spread into the beds but otherwise Apium nodiflorum was the most frequent plant with occasional Scrophularia aquatica, Mentha sp., Myosotis scorpioides, Rorippa nasturtium-aquaticum and Glyceria fluitans agg. Pipeline In September, 1954, a trench about 5 feet deep was dug from Hundred Pound Bridge to the Tunnel. From Hundred Pound Bridge it ran to the west of, and roughly parallel to, Common Road (varying up to 20 yards away from it in Western Plain) until it reached Eastern Ditch when it crossed over to the east of Common Road (and never more than a yard from it) until it ceased just short of the Tunnel. A water pipe was laid in this trench and the earth replaced. This left a belt of bare earth about 5 yards wide right across the Common. In 1955 this belt was divided up into 9 divisions of approximately equal length and the species in each division listed. Many of the plants recorded were those found in the adjoining plains or woods and these have been largely ignored in the following lists. Many had, for example, sprouted from old roots, etc., or, at most, seeded from plants a few yards away. It must not be thought that the pipeline quickly reverted to its original flora. In the south it ran through S.E. Wood and the undergrowth in the belt was cleared, allowing a greater growth of woodland herbs. Across Western Plain the dominant Pteridium aquilinum was killed and a luxuriant stand of Deschampsia cespitosa took its place. The breaking of Pteridium aquilinum fronds weakens the plant but although it has some regenerative powers breaking up of the rhizomes usually kills it. In 1956 the 5-yard belt was almost free from Pteridium. Also across W. Plain young Quercus robur seedlings appeared in the cracks in the clay. If successful these seedling oaks may mark the pipeline in a very permanent way. It seems likely that if they fall in grass, acorns rarely reach the soil and therefore fail to take root, whereas the bare cracks in the clay provide an immediate germinating place. Holcus lanatus, which is locally abundant on the plains, became dominant in several places in the belt in I.o.W. Plain and by the I.o.Wight. Wastes In 1955 and 1956, 30 areas of disturbed soil or waste places were examined. These were a piece of rough ground by Rydall, used as a car-park, rough ground by the Tunnel, a bomb-crater in S.E. Wood completely overgrown, two disturbed areas and an overgrown allotment by the Shingled House, area by Banks Cottage periodically used for chickens, rough ground by entrance to one of the houses at I.o.Wight, rough ground at High Point, area of recently cleared woodland to north of marshy part at I.o.W. Pond, fresh plantation of trees to south of I.o.W., recently dug ditch (no water) in Central Plain, two small deturfed areas and 16 small dumps of earth, bricks or chalk (chiefly used for making up tracks) in various parts of the Common. The deturfed areas and the small dumps were poor floristically, supporting mainly a few casuals and some plants from surrounding areas and in all cases only the aquatic and wasteland plants are considered here. THE SURVEY OF BOOKHAM COMMON 83 It is tempting when considering dumps of materials to think that the plants occurring are introduced. Similarity to the pipeline does, however, throw doubt on this as the pipeline had no introduction of soil although admittedly seeds could have been introduced on wheels of vehicles. Undoubtedly some are introduced, as for example, a record of Cymbalaria muralis (a plant that cannot be considered a wasteland plant), amongst bricks used for making up a track in 1951. Many of the wasteland plants, however, probably exist precariously jumping from one area of disturbed soil to another, on the Common. The Tables All the plants found in the Surveys which can be considered aquatic or wasteland plants are now listed in five tables according to their general habitats as observed by the writer in Surrey. These tables show to what extent each plant was found in the Surveys — in the case of I. o. Wight, L.E., U.E., and Sheepbell Ponds the frequencies of each plant are given. Fourteen Minor Ponds, two Hollows, 15 divisions of the Streams, nine divisions of the Pipeline and 30 Wastes were observed, and in the tables is shown the number of these in which each species occurs. The nomenclature adopted in the tables and elsewhere follows Dandy (1958) for scientific names and Rayner (1927) for popular names as far as possible. Abbreviations used in the tables and elsewhere are: — r rare o occasional f frequent a abundant d dominant 1 local(ly) v very c co- I.o.W. Isle of Wight L.E. Lower Eastern S.E. South Eastern U.E. Upper Eastern Table 1 plants are those that in the author’s experience do not grow away from standing or flowing w'ater although some such as Callitriche sp. will tolerate a good deal of drying up whereas others such as Myrio- phyllum alterniflorum will not. The few records for the wastes and pipeline are for wet places. Nymphaea alba recorded for U.E. Pond was almost certainly washed down from a small garden pond at the top of Greendell Ditch. Equi- setum palustre occurred on the Common only in what were the three lower ponds of the Hollows Valley, viz., E. Hollow, W. Hollow and I.o.W. Pond in each case at their western ends, and the marsh below I.o.W. Pond. Table 2 plants are usually associated with standing or flowing water but are occasionally found away from it. One important feature of the aquatic habitat is the frequent occurrence of bare soil or mud due to a temporary or permanent fall in water level. This appears to provide the connecting link between aquatic, marshland and wasteland habitats and could account for much of their common flora. Bare earth or mud may ensure lack of competition in germination and/or growing periods either above or below ground. In addition the water may distribute seed or parts of plants capable of regeneration. Of the plants that require bare soil for germination, Salix cinerea is prominent, being characteristic of the edges of ponds where it germinates on the bare mud. On the City Bombed Sites it germinated in the early 84 THE LONDON NATURALIST, NO. 39 Table 1 Aquatics and Semi-aquatics c. £ 6 Equisetum fluviatile (Water Horsetail) Id E. palustre (Marsh Horsetail) ... ... 1 Ranunculus flammula (Lesser Spearwort) ... o R. sceleratus (Celery-leaved Crowfoot) R. aquatilis (Water Crowfoot) ... ... r Nymphaea alba (White Water-lily) ... Rorippa nasturtium-aquaticum (Water-cress) r Epilobium palustre (Marsh W'illowherb) ... r Myriophyllum alterniflorum (Water Milfoil) Callitriche sp. (Water-starwort) ... ... r Hydrocotyle vulgaris (Marsh Pennywort) ... r Apium nodiflorum (Procumbent Marshwort) A. inundatum (Least Marshwort) ... ... r Oenanthe fistulosa (Tubular Water-dropwort) Myosotis scorpioides (Forget-me-not) ... f M. secunda (Creeping Forget-me-not) M. caespitosa (Tufted Forget-me-not) Veronica scutellata (Marsh Speedwell) ... r V. anagallis-aquatica agg. (Water Speedwell) Mentha aquatica (VV ater Mint) ... ... f Ly copus europaeus (Gipsywort) ... ... f Stachys palustris (Marsh Woundwort) Scutellaria galericulata (Greater Skullcap) Galium palustre (Marsh Bedstraw) ... ... a Bidens cernuus (Nodding Bur-marigold) ... o Alisma plantago-aquatica (Greater Water-plantain) f Potamogeton natans (Floating Pondweed) . . 1 P. crispus (Curled Pondweed) Iris pseudacorus (Yellow Iris)... Lenina polyrhiza (Greater Duckweed) L. trisulca (Ivy-leaved Duckweed) ... ... f L. minor (Lesser Duckweed) ... ... o Sparganium erectum (Branched Burreed) ... Id S. emersum (Un-branched Burreed) ... r Typha latifolia (Broad-leaved Reedmace) ... Id Eleocharis palustris (Marsh Clubrush) ... f Scirpus fluitans (Floating Clubrush) Glyceria fluitans agg. (Floating Meadow Grass) f Q c u or y CL U4 pi JD Q. D u U C c J o o *— r 3 4> w 4> C/3 13 c. J D % t; -*-* Id Id 2 r 1 1 1 1 2 1 2 r 1 2 r r r 2 2 1 f 4 1 1 2 1 r r 2 1 11 r 1 1 f o r 2 2 3 1 r 2 1 1 o f 2 2 4 f o o 4 2 1 1 2 1 o r 5 2 o o o 1 f o 7 1 1 1 2 1 o cd 1 1 o o 1 o o cd 3 Id Id 4 2 ] 1 2 If 2 1 1 o f 5 2 years on the bare dust and rubble, but in neither case does it germinate when the area becomes overgrown. It might be pointed out that Salix cinerea is less resistant -to drought than S. caprea which is included in Table 3. Other plants also found in such permanently dry places are Rorippa islandica, Epilobium hirsutum, Salix fragilis and S.viminalis. Most of the other plants listed are plants found in grassy or disturbed places, or woods which in many cases would be reasonably damp at least at some time of the year. Scrophularia aquatica although characteristic of ponds and streams is an occasional plant on chalk slopes in Surrey (chiefly by woodland paths). To a lesser extent Cirsiurn palustre and perhaps Pulicaria dysenterica have this odd trait. Table 3 plants are more often found in grassy places (which may or may not be damp) than in ponds and streams. Some of them, e.g. Equisetum arvense , can be found in very dry places; on the other hand Cardamine flexuosa is found elsewhere only in damp woods. Solatium dulcamara is exceedingly versatile, its frequent habitats being ponds, streams, chalk downs, hedgerows and dry places such as the City THE SURVEY OF BOOKHAM COMMON 85 Table 2 Plants Usually Associated with Water -3 Barbarea vulgaris (Winter Cress) Rorippa islandica (Marsh Yellow Cress) Lychnis flos-cuculi (Ragged Robin) ... Stellaria alsine (Bog Stitchwort) Lotus uliginosus (Greater Birdsfoot Trefoil) Filipendula ulmaria (Meadowsweet) ... Peplis portula (Water Purslane) Epilobium hirsutum (Great Hairy Willowherb) Conium maculatum (Hemlock) Angelica svlvestris (Wild Angelica) ... Polygonum hydropiper (Water Pepper) Rumex conglomeratus (Sharp Dock)... Salix frag ills (Crack Willow) S. viminalis (Osier) S. cinerea (Grey Sallow) Lysimachia nummularia (Creeping Jenny) . . . Scrophularia aquatica (Water Figwort) Mentha x verticillata (Whorled Mint) Scutellaria minor (Lesser Skullcap) ... Galium uliginosum (Bog Bedstraw) Pulicaria dysenterica (Common Yellow Fleabane) Gnaphalium uliginosum (Marsh Cudweed) ... Cirsium palustre (Marsh Thistle) Juncus bulbosus (Lesser Jointed Rush) Car ex otrubae (Fox Sedge) Alopecurus geniculatus (Kneebent Foxtail Grass) I.o.W. Pond L.E. Pond U.E. Pond a. v JO o. u V JC Minor Pond Hollows C/5 E « 0) u Co Wastes Pipeline 6 1 1 1 f 1 o 1 2 6 r 1 f 1 Id 4 2 15 3 8 1 1 4 r r r f 3 2 3 4 o r o 1 2 8 3 r r 1 2 1 Id o a f 8 2 3 2 1 f o f 2 2 1 7 r 1 1 2 o 2 2 1 6 1 r 6 2 2 1 2 1 1 f o 2 2 5 r Bombed Sites. Salisbury (1952) mentions it as a frequent plant of chalk scrub and says it occurs on diverse types of soil, but especially where rich in bases or in hollows or in water where the soil is enriched by bases leached out from higher ground. It is of course possible that one form of a species may live in dry habitats and another form in wet habitats, this applying to plants in Table 2 as well. Agrostis canina in the wet conditions of I.o.W. Pond and S.E. Pond is usually the fasciculate sub-species canina. Glyceria fluitans agg. listed in Table 1, grows erect in muddy places, but seems to adapt itself to some extent when in deep water by having floating leaves. Table 4 perennial and biennial wasteland plants are normally able to maintain themselves in competition with grassland vegetation for some years and are not usually considered plants of wet places. Most of them occurred in the wasteland habitat on either side of the streams caused by the dumping of mud from stream clearing. Mention must be made of some plants whose relations with the streams or ponds cannot, however, be lightly dismissed: — 1 . Anthriscus sylvestris, although largely a hedgerow plant is to be found occasionally in abundance along streams in Surrey, often occurring as at Bookham Common with Alliaria petiolata which is of similar character. 2. Dipsacus fullonum is not normally found in wet places but on Bookham Common it was confined to or near to the banks of I.o.W. Ditch, 86 THE LONDON NATURALIST. NO. 39 Table 3 Plants often Associated with Water Equisetum arvense (Field Horsetail) ... ... r Ranunculus repens (Creeping Buttercup) ... f Cardamine pratensis (Cuckoo Flower) C. flexuosa (Perennial Hairy Bitter Cress) . . . Hypericum tetraplerum (Square-stalked St. John’s Wort) Potentilla anserina (Silverweed) ... ... f P. erect a (Upright Tormentil) ... ... r Epilobium cf. obscurum (Dull-leaved Willowherb) r Salix caprea (Sallow) Solanum dulcamara (Bittersweet) ... ... f Mentha arvensis (Com Mint)... Juncus tenuis (Slender Rush) ... /. bufonius (Toad Rush) ... ... ... r J. inflexus (Hard Rush) ... ... ... o /. effusus (Loose-flowered Soft Rush) ... a J. conglomeratus (Soft Rush) ... ... r J. acutiflorus (Sharp-flowered Jointed Rush) J. articulatus (Shining-fruited Jointed Rush) r Scirpus setacea (Bristle Clubrush) Carex /lava agg. (Yellow Sedge) C. hirta (Hairy Sedge) . . ... ... ... 1 C. remota (Remote-spiked Sedge) ... ... r C. ovalis (Oval Sedge) ... ... ... r Agrostis canina (Brown Bent Grass) ... f r o o r r o o r r o C/2 £ o "5 X 1 2 2 2 1 2 2 1 2 T 1 C/2 £ C3 V C/3 s. V C/2 73 £ u c "u c. '£ 1 1 7 8 3 1 1 1 1 4 2 3 1 5 3 5 4 4 1 1 5 5 1 9 1 1 1 1 2 1 1 Bookham Stream and Banks Stream. This is possibly the only suit¬ able wasteland habitat available to it ; the plains and other grassy places normally being too overgrown. 3. Calystegia sepium, occasional along streams and in ponds and the Hollows (but also elsewhere), was apparently limited in its distribu¬ tion on the Common, not, directly by wetness or dryness nor by requiring a wasteland habitat, but chiefly by the occurrence in turn of Epilobium hirsutum over which it commonly twines. On the other hand Calystegia silvatica was on the Common, confined to a wire fence near Peacedene. Both species are normally found more in wasteland habitats than grassy places. 4. Urtica dioiea occurs frequently along the streams and many of the ponds and the Hollows but is probably dependent upon the bare soil. Urtica dioiea is very tolerant of flowing water and occurs, for example, in abundance on the low banks of the Beverley Brook on Wimbledon Common where every winter it is swept by the brook in flood. The creeping stems may well be scoured out and deposited further along where they root. This may be the means of distribu¬ tion of many stream plants such as Apium nodiflorum, Rorippa nasturtium-aquaticum and Epilobium hirsutum. 5. Epilobium parviflorum occurred in several spots in standing water in I.o.W. Pond apparently hybridizing freely 'with E. palustre. Table 5 annuals are purely casuals and they exist only where there is bare and/or disturbed soil. Polygonum persicaria is very tolerant of standing or flowing water and in Surrey is occasionally to be found in the water at the edges of ponds THE SURVEY OF BOOKHAM COMMON Table 4 Perennial and Biennial Plants of Waste Places 87 A lliaria petiolata (Garlic Mustard) ... Silene alba (White Campion) Malva neglecta ( Dwarf Mallow) Potentilla reptans (Creeping Cinquefoil) Epilobium parviflorum (Small-flowered Willowherb) o Oenothera sp. (Evening Primrose) ... Anthriscus sylvestris (Wild Chervil) Aegopodium podagraria (Gcutweed) Foeniculum vulgare (Fennel) ... Heracleum sphondylium (Hogweed) Rumex crispus (Curled Dock) R. obtusifolius (Broad-leaved Dock) Urtica dioica (Common Nettle) ... ... r r Calystegia septum (Hedge Bindweed) ... o Lamium album (White Deadnettle) ... Dipsacus fullonum (Wild Teasel) Tussilago farfara (Coltsfoot) Matricaria matricariodes (Rayless Mayweed) Chrysanthemum parthenium (Feverfew) Artemisia vulgaris (Mugwort) Arctium sp. (Burdock) Cirsium vulgare (Spear Thistle) C.arvense (Creeping Thistle) ... ... ... r Centaurea nigra (Black Knapweed) Lapsana communis (Nipplewort) Lactuca serriola (Prickly Lettuce) Crepis vesicaria ssp. taraxacifolia (Beaked Hawksbeard) Taraxacum officinale agg. (Dandelion) Dactylis glomerata (Cocksfoot) c c a D y y ir. o la 2 2 1 3 1 1 Si c 1 '/ r. y '■J £ .rz u V 13 r ■ > IT. > CL 6 3 1 4 1 1 5 1 1 1 5 1 1 1 1 6 1 4 16 3 5 2 11 5 4 7 1 3 6 1 3 3 4 1 1 3 1 1 1 4 13 4 1 1 1 1 112 1 1 1 2 5 3 1 3 or streams. Galium aparine is occasional along the streams of the Common chiefly associated with Urtica dioica over which it climbs. By the Beverley Brook on Wimbledon Common it is abundant again with Urtica dioica and is flooded every year. Cerastium glomeratum recorded in several places along the pipeline is occasional elsewhere on the Common in the wet ruts of woodland tracks. Summary 1. Ponds and Hollows. (a) The Hollows Valley (i) Originally fish-ponds formed by damming the valley at five points. (ii) Two of these ponds are now' only marshes and the remaining three are very overgrown. (iii) The sequence of dominant plants after the open water community is inferred as Sparganium erectum, Equisetum fluxiatile, Epilobium hirsutum , finally degenerating into a mixed marsh and then possibly a community of Deschampsia cespitosa. (iv) Salix cinerea forms lines of trees at successive water levels at the edge of each of the ponds. (b) Sheepbell Pond A deeply shaded but permanent pond dominated by Lemna polyrhiza , L. minor and Riccia “ fluitans ” agg. 88 THE LONDON NATURALIST, NO. 39 Table 5 Annual Plants of Waste Places (None of these species was recorded from U.E. or Sheepbell Ponds) •o c o 0. i 6 t3 C o a. tu J Papaver rhoeas (Corn Poppy) Fumaria officinalis agg. (Common Fumitory) Raphanus raphanistrum (Wild Radish) Coronopus squamatus (Swine’s Cress) C. didymus (Wart Cress) Capsella bursa-pastoris (Shepherd’s Purse) Erysimum cheiranthoides (Treacle Mustard) Sisymbrium officinale (Hedge Mustard) Cerastium glomeratum (Broad-leaved Mouse-ear Chickweed) Stellaria media (Common Chickweed) Spergula arvensis (Com Spurrey) Chenopodium polyspermum (Many-seeded Goosefoot) C. album agg. (White Goosefoot) C. rubrum (Red Goosefoot) ... A triplex pa tula (Spreading Oracbe) A. hastata (Halberd-leaved Orache) Aphanes arvensis agg. (Field Lady’s Mantle) Euphorbia peplus ( Petty Spurge) Polygonum aviculare agg. (Knotweed) P. persicaria (Common Persicaria) ... r r P. lapathifolium (Pale Persicaria) P. convolvulus (Climbing Buckwheat) Anagallis arvensis (Scarlet Pimpernel) Solanum nigrum (Black Nightshade) .. Chaenorhinum minus (Small Toadflax) ... r Veronica arvensis (Wall Speedwell) ... V. hederifolia (Ivy-leaved Speedwell) V. persica (Buxbaum’s Field Speedwell) Galeopsis tetrahit agg. (Common Hempnettle) Lamium purpureum (Red Deadnettle) Plantago major (Greater Plantain) ... Galium aparine (Cleavers) S. sylvaticus (Heath Groundsel) S. vulgaris (Common Groundsel) ... ... r Conyza canadensis (Canadian Flea-bane) ... Tripleurospermum maritimum ssp. inodorum (Scentless Mayweed) Sonchus oleraceus (Common Sowthistle) S. asper (Rough Sowthistle) Lolium multiflorum (Italian Rye Grass) Poa annua (Annual Meadow Grass) C/5 •o c o a. u O c -si 5 _c o 1 1 1 1 2 1 C/3 £ C/3 V u c