30 Aliens - Urtica membranacea in Warwick / Primula helodoxa at Studland, Dorsetlished for several years. Eric Clementconfirmed the identity and thought it likely thatthis was a first British record.This annual nettle has a Mediterranean andWestern European distribution, extending toNorthern France (lR. Edmondson, FloraEuropaea (2 nd Edn.) 1, 80). It could bemistaken for the Small Nettle, Urtica urens,which also is annual and monoecious, withmany female inflorescences and fewer maleones. However, U membranacea has unilateralmale racemes which lack flowers on theirunder-surfaces, which are expanded andmembranous. These terminal racemes arepurple-tinged when immature, contrasting withthe pale green leaves, a character lost in driedmaterial (see back cover).Unlike both of the common British nettleswhich have four small linear stipules on thestem near the petiole junctions, this alien nettlehas apparently two ovate stipules, formed by thefusion of adjoining pairs of stipules ('connate').The photographs (see back cover) by John andVal Roberts clearly show these easily overlookeddistinctions.Eric Clement suggested that this nettle'sarrival and persistence may be a further instanceof the effects of climate change; Britain may beacquiring a more Mediterranean element to itsflora. Warwick, a Midland town, has experiencedrecent winter temperatures of -10°C, butthe location of the plants, in a town centresurrounded by buildings, would have protectedthem. They have also survived at least oneattempt at eradication by the town's weed-killer,protected by wheelie-bins and parked motorbikes!Thanks to Eric Clement for his prompt andencyclopedic help, and also to John and ValRoberts for the photographs.Primula helodoxa at Studland, Dorset (v.c. 9)EnwARD PRATT, 7 Bay Close, Swanage, Dorset. BH191RESteve O'Connell, the National Trust wardenwho discovered Scorzonera humilis (Viper'sgrass)on Corfe Common a few years ago, foundPrimula helodoxa Balf. f. making a splendiddisplay by a small stream lOOm from the sea atthe south end of Knoll Beach car park(SZ034.832) in May 2006 (see Colour Section,Plate 2). Eric Clement (EJC), who kindly determinedit, says it is the first escape of this speciesinto the wild known to him in Britain. Therewere fifty-eight flowering stems, and other nonfloweringplants. The species is grown in agarden upstream, in which they propagate freelyby seed.The stems are 60 to 110cm tall, and mealybelow the whorls of flowers. They arise from arosette of broadly lanceolate obtuse leaves up to40cm long, widest above their middle, irregularlyserrate, and which taper gradually intotheir base. They have sparse very short hairs onthe upperside and are shortly pubescent underneath.The cowslip-coloured flowers are in upto 8 whorls on the stem, with from 10 to 22flowers in a whorl. The lowest whorls comesinto flower first and so on upwards, so theflowering season of a colony is over twomonths. Their corollas tubes are 16mm long,and their lobes are 25 to 27mm in diameter. Thecalyces are mealy and 6mm long, includingacute lobes of 2mm. The pedicels elongate infruit and are 6 to 19mm. The bracts are linearand 6 to 16mm long.EJC has kindly told me that P. helodoxa is anative of Yunnan (S.W. China) and is part of acomplexity of taxa that extend from India toIndonesia. Some recent literature, e.g. TheEuropean Garden Flora, Vol. 5, p. 527 (1997),takes a very broad view and lumps all the taxainto P. prolifera Wallich.EJC adds that the epithet helodoxa is presumablyderived from the Greek - helos, marsh, anddoxa, glory - a very appropriate description. Nosatisfactory English name appears to exist. Ihave heard Campanula Primula used, but it hasbeen also used for a group of similar species.Candelabra Primula has been used, but is alsoused for a similar species. Bearing in mind thatStace (1997) uses Japanese Cowslip for asimilar whorled species, I suggest YunnanCowslip.ReferencesRICHARDS, A.J. & RICHARDSON, J.E. 1997. PrimulaLinnaeus, in CULLEN, J. et al. (eds.). The EuropeanGarden Flora 5: 511-535. Cambridge UniversityPress.STACE, C.A. 1997. New Flora of the British Isles.Cambridge University Press.
Colour Section1Fig. 2. Ripe nuts of Isolepis setacea (left, E.Norfolk, June 2002( and I. cernua (right, HoltLowes, E. Norfolk, June 2002)Fig. 1. Spikelet of Isolepis cernua showing threestamens projecting from a single glume(Holt Lowes, E. Norfolk, June 2002)Fig. 3. Semi-ripe fruits of Isolepis cernuashowing three filaments (i.e. stamens) and threestigmas (Beeston Common, E. Norfolk, August2006)Fig. 4. Isolepis cernua showing long bracts(Bees ton, E. Norfolk, June 2006).All Isolepis photos (see p. 13) S. Harrap © 2006Gentiana verna (Spring Gentian) on limestonegrassland, Northern Pennines (see p. 8).Photo L. Robinson © 2005
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