has been proposed for one or other of them, but Tausch's description (1834) is too vague: “Batrachium; caule abbreviato natante, foliis omnibus immersis petiolatis capillaceo-multifidis, floribus minimis sub-12-andris oligocarpis, carpellis hispidulis obtusis." Of the two it rather applies to R. divaricatus. Segregatory grouping of the plants here comprised under R. aquatilis L. var. y: I. R. DIVARICATUS Schrank (1789). lusus MACRANTHUS. Var. 2. ERADICATUS = R. aquatilis var. eradicatus Læstad. (1842). lusus MACRANTHUS. lusus FURCATUS. R. Rionii Lagger (1848). · Var. 3. RIONII = == Var. 5. SPHÆROSPERMUS R. Aschersoni Freyn (1881). = R. sphærospermus Boiss. et Var. 6. CABOMBOIDES = R. hydrocharis var. cabomboides Var. 7. TERRESTER = R. Drouetii f. terrestris G. C. Druce (1897). II. R. TRICHOPHYLLUS Godron (1847). Var. 1. COMMUNIS. forma TYPICA. forma FILICAULIS Rouy et Fouc. (1893). forma DOLICHOPODA = R. dolichopodus A. Kerner forma NUTANS. (1893). forma CARNOSA = Batrachium confervoides var. car nosum J. M. Norman (1893). forma NANA Beauverd (1904). Var. 2. TERRESTER Godron. I. forma CREBRIOR. forma GERMANICA. RANUNCULUS DIVARICATUS Schrank. The history of this species from 1539 to 1739 is epitomized in the following list of names of the plant, verified by comparison of the text and figures in the authors cited: Sam Kreut, Bock (afterwards Tragus) Kreutterbuch, ii. ch. 43, p. xxxii (Strassburg, 1539), reprinted as Kreuter Buch (Strassburg, 1546). Alga prima, Tragus (formerly Bock), Latin edition by D. Kyber, lib. ii. cap. 44, p. 687 (Strassburg, 1552). Ranunculus chamameli foliis, Gesner Tab. Collect. 104 (Strassburg, 1553). Millefolium aquaticum quoddam, Gesner, l. c. p. 90b. Ranunculus tertius, Gesner Hort. Germ. p. 275 (Köln, 1561). Alga palustris et fluviatilis, Gesner Stirp. Collect. (Zürich, 1587). Millefolium maratriphyllon tertium, flore et semine Ranunculi aquatici Hepaticae facie, Lobel Icones, 791 (1581); Johnson (1633). Ranunculus aquatilis alter, Cesalpini De Plantis, lxiv. c. 2 (1583). Foeniculum aquaticum tertium, Tabernaemontanus, Kräuterbuch, p. 71 (1588); it is on the figure of this plant, which very clearly represents the water-fennel, that R. divaricatus is founded. Millefolium aquaticum flore albo, Clusius Rar. Plant. Hist. (1601). Ranunculus aquaticus foeniculaceus trichophyllus, Fabio Colonna Ecphrasis, t. ad p. 316 (1616); a most expressive name and the best and most characteristic figure of the plant in preLinnean works. Millefolium aquaticum, foliis abrotani, ranunculi flore et capitulo, Bauhin Pinax, lib. iv. sect. 3, n. vi. p. 141 (1623). Ranunculus aquaticus capillaceus, Bauhin, l. c. lib. v. sect. 3, n. vi. p. 180; Morison Plant. Hist. Univ. ii. p. 442, s. 4, t. 29, f. 32 (1680); Tournefort Instit. Herb. 291 (1700). Ranunculus aquaticus omnino tenuifolius, J. Bauhin Hist. Plant. iii. p. 781, f. 2 (1651); Ray Hist. Plant. p. 586 (1686); Syn. Meth. Stirp. Brit. p. 249 (ed. 2, 1696). Fine Water Crowfoot, Petiver Herb. Brit. Cat. t. 39, f. 2 (1713). Ranunculus aquaticus albus fœniculi folio, Barrelier Pl. Hisp. Gall. Ital. Obs. Íc. p. 57, t. 566 (1714). Ranunculoides foeniculo folio breviore, Vaillant in Bot. Paris, 1727, p. 170. The earliest reference to our plant is that of Bock in 1539, where he says: "Im wasser findt man vilerley Sam Kreutter wachsen etlichs ist gantz zinnelecht mit wilen gewerblin, darumb würt es lang wie das Weggrass. In Kyber's Latin edition of 1552, which is a book nearly as rare as the German editio princeps, the plant is called "Alga prima," and is described in these words: Primum genus nostræ Algæ, herba est geniculata et prælonga, Centumnodiæ vulgo vocatæ non absimilis, foliis admodum incisis. Hæc Junio mense elegantissimos, candidos, herbæ Fragariæ similes flores profert, quibus decedentibus capitula rotunda, echinata, instar Ranunculi succedunt. Herba est viridis, et quæ aquis fluentibus gaudeat." The character which suggests that the plant belongs here rather than to R. fluitans is "capitula rotunda, echinata," as in the latter species the fruiting-spike of pistils is rather oblong and glabrous; but the fine distinctions of modern species can scarcely be gauged with precision in the earliest descriptions not supplemented with a figure. The description which follows was drawn up mainly from plants seen growing in the Lower Brent district of Middlesex, between Greenford and Perivale, on a detached patch of alluvial soil surrounded by the London clay, coloured yellow in the map in Trimen and Dyer's Fl. of Middlesex. Several descriptions of the species, and the examination of many plants from other localities, were also laid under contribution (all generic characters being eliminated). RANUNCULUS DIVARICATUS Schrank Baiersche Flora, ii. p. 104, n. 859 (1789); et Prim. Flor. Salisburg. p. 145, n. 527 (1792); Mönch Meth. Plant. p. 214 (1794); non Koch in Sturm Deutschl. Fl. heft 67 (1835), nec Ledeb. Fl. Rossica, i. p. 28 (1842), nec Gren. et Godr. Fl. de France, i. p. 25 (1847), nec plurium aliorum. Aquatilis, ac simul omnino submersus (vel casu ad loca siccanea terrester), gracilis, perennis, 2-4 dem. Caulis basi et ad nodos inferiores radicans, fibris radicalibus albis, fistulosus elongatus obtuse quadrangulus multum ramosus, hispidulus vel glaber. Folia læte viridia, omnia uniformia flaccida plus minus petiolata multifido-capillacea, repetite laxiuscule trifurcata, ambitu divergentia, internodium subæquantia vel eo paullum breviora; laciniæ divaricatæ in segmento sphæræ undique obvie patentes, haud in planum orbiculare disposita, partitionibus primariis subsequentibus subæquilongis vel parum longioribus, extra aquam plantâ ablatâ collabentes. Stipulæ parvæ latiusculæ petiolo -adnatæ vaginantes membranacea breviter auriculatæ, sæpius glabræ vel solum superiores pilosæ. Alabastra primum ovata, modo ante anthesin oblonga. Pedunculi oppositifolii uniflori, foliis plus minus æquilongi vel paullum excedentes, florem versus haud attenuati, teretes striati, glabri vel hispiduli, 21–31-vel 4 ctim.; fructiferi graciles longius incrementum capientes, crassitie receptaculi, basi recurvi superne subrecti. Flores 9 mm. in diam. et minores, stellati, proterandri. Sepala primum patentia demum reflexa, elliptica concava glabra, viridia sed maculis sæpe atro-violaceis picta, marginulo albentia. Petala alba, ungue flavo, oblongo-cuneata, non contigua, calycem vix superantia, basi foveâ flavâ nectariferâ rotundatâ nudâ instructa, angusta, in unguem inferne non contracta, striolata, venis approximatis 5-7; mox caduca. Stamina 5-10 (vel interdum 12), pistilla plerumque superantia. Spica fructifera globosa. Receptaculum valde hispidum, ovato-oblongum. Carpella in capitulum lateraliter alligata, 20–35 vel ad 45, interdum usque ad 60 vel etiam ad 85; turgida stylo deciduo terminata, pilis brevibus crassis griseis hispida vel sæpe quidem demum glabra, 13-14 vel tantum 1 mm. longa, semi-obovata immarginata tenuiter carinata, apice rotundato-inflata, sed secus oram sublongiorem superiorem planiuscula, transverse corrugata et demum magis rugosa, rugis 7-9; stylus brevis exilis, fere ad extremitatem pistilli diametri longi insertus, hinc subcentralis, stigmate oblongo-ovato papillis albidis densis longis cylindricis instructo. Hab.-World-wide in its distribution. The northern limit of the species is Berlevåg, in the amt of Finmarken, on the north coast of Norway, lat. 70° 50' (T. Fries, ex J. M. Norman, Norges Arktiske Flora, ii. [1895] 33)-var. eradicatus. The southern limit of the species is in Tasmania along the Lake River, near Grindelwald and Formosa, in the county of Westmorland (Gunn, n. 1938, in Herb. Kew. coll. 1844), see also Hooker f. Fl. Tasmaniæ, i. 5 (29 Oct. 1855), and along the South Esk River and near Evan dale, in the county of Cornwall, lat. 42° (C. Stuart in herb. F. Mueller, et ex Bentham, Fl. Australiensis, i. 1863, p. 10)-var. cabomboides. I have not seen Fries's Norwegian specimens; the most northerly examples I have examined being those collected by Berggren (1870) at Claushavn, on the west coast of Greenland, lat. 69° 15' (in Herb. Kew.), examples cited also by Lange, Consp. Fl. Groenland. p. 54 (1880). Fries's examples are referred to in Botaniska Notis. 1864, in a paper, "En botanisk resa i Finmarken 1864." In general floras the northern limit of the species is given as Iceland, from which island there are specimens in Herb. Kew. collected by C. C. Babington, near Reykjavik, in 1846-but this is some distance south of the Arctic Circle. This var. eradicatus is the "Ranunculus aquatilis" of Linnæus's Fl. Lapponica, but there is no specimen in Herb. Linn. In one of the most recent local floras, MM. L. & M. Gortani, in Fl. Friulana, ii. 208 (Maggio 1906), give five varieties under R. aquatilis, of which three include vars. trichophyllus, paucistamineus, and fœniculaceus. The first is stated to be common in still and slow-moving water. The second occurs in slow-moving and muddy water. The last, which is obviously intended for R. circinatus, is found growing in water issuing from lakes. According to Grenier, Fl. de la Chaine Jurassique, 16 (1865), the present species grows in the ponds of the plain, but is not found in the mountains nor in the fir zone, where it is replaced by R. trichophyllus. See also Rapin, Guide du Botaniste dans Vaud, ed. 2, p. 12, n. 3 (1862). Var. 1. COMMUNIS: ut supra. Lusus MACRANTHUS.-Flores majores, 15 mm. in diam., petalis minus caducis. Pedunculi firmiores longiores, sub anthesi 2-3 cm., post anthesin fructiferi usque ad 4-5 cm. Caulis magis angulatus. Syn.-R. trichophyllus f. Martini Lamotte, Prodr. Fl. Plat. Centr. France, 43 (1877), not a species as given in Ind. Kewensis. Named by Lamotte after M. Martin, President of the Civil Tribunal of Romorantin, who studied the Batrachian Ranunculi and drew his attention to this large-flowered form. Hab.-France: Saint-Loup in the Department of Loir-et-Cher (E. Martin); Riom, in deep ditches along the railway, and near Clermont-Ferrand, in the Department of Puy-de-Dôme (Lamotte); and Les Gazeriers, commune of Sussat, near Ebreuil, in Allier (Lamotte). Var. 2. ERADICATUS. con Pusillus, 2-3 dem., depauperatus. Folia 12-18 mm., fervoidea. Pedunculi 1-2 cm., filiformes. Alabastra non depressa. Flores 7-8 mm. in diam. Petala calyci æquilonga. Stamina 5-10. Carpella 20-25, in statu juniore hispida demum glabrescentia, primum olivino-atrescentia, demum brunnea; stylus reflexus. Geogr. limits.-W.-Claushavn, on the west coast of Greenland, as stated above (Berggren). N.-At Berlevåg, in the amt of Finmarken, Arctic Norway, as stated above (T. Fries). E.-E. Siberia, on the Sajan Mountains (E. Regel, Pl. Raddeanæ i. p. 39, n. 50, 1861—“ Ř. aquatilis var. Sajanensis "). S.-Russian Turkestan: Ala-Tau Mountains, north of Lake Issik-kul, in the province of Semirietshensk (ex Hiern, in Journ. Bot. 1871, p. 102)-lusus furcatus. In the British Isles found only on Fingask Loch, Perthshire, and on Rescobie Loch and Balgavie Loch in Angus, flowering and fruiting under water two to five feet below the surface (see Journ. Bot. 1880, p. 344). Its reported occurrence near Dublin (Corry in Journ. Bot. 1882, p. 222) is very doubtful, both from the nature of the locality and from the fact that a careful observer like Mr. N. Colgan does not record its occurrence in his Fl. of Dublin (1904). In France it is found only in three departments: BassesAlpes, on the Lake of Ligny near Annot (Reverchon); AlpesMaritimes, in mountain-pools (Reverchon); Savoie, at the bottom of a pool in the forest of Aut-du-pré on Mt. Mirantin, in the commune of Conflans, on a cliff of talc-schist at 1000 metres above sea-level (Billot, exs. n. 2605, R. lutulentus "). It is found also in Iceland (C. C. Babington, 1846, in Herb. Kew.), Swedish Lappland (the earliest record of this plant, by Læstadius, 1842), Finnland, W. Central Russia, in Germany only in the Hartz Mountains (Hampe), Austria, in the province of Tirol (A. Kerner, Sched. Fl. exs. Austr. Hung. n. 1706), also in Switzerland. The south limit in Europe is in the Alps of the Alpes-Maritimes (Reverchon ex Burnat, Fl. des Alpes-Maritimes). Syn.-R. aquatilis var. eradicatus Læstad. (1842); Batrachium eradicatum Fries (1843); B. confervoides Fries (1845); Ranunculus confervoides Fries (1846); R. paucistamineus var. borealis Beurl. in Bot. Notiser, 1852, p. 156; R. aquatilis var. Sajanensis Regel (1861); R. lutulentus Song. et Perrier (1859); B. admixtum Nyl. et Saell. (1859); R. trichophyllus var. demersus N. E. Brown, in Engl. Bot. ed. 3, Suppl. 12 (1891). The stipules are more adnate to the petiole (three-fourths of its length), thus more of the nature of a true sheath, and more usually quite glabrous, but not so in the Scottish plant, where they are pubescent. As compared also with the previous variety, the sepals are dark violet with a green median nerve. I can find no specific difference whatever in authentic specimens of R. eradicatus, R. confervoides, and R. lutulentus, not even in size. In Arctic Norway it is in flower from 7th July to 15th September, and after 13th August it may be found in fruit. (To be continued.) WATSON EXCHANGE CLUB REPORT, 1906-7. [IN accordance with our usual practice, we give some extracts from the most recent Report of the Watson Botanical Exchange Club. The Report contains a large number of notes on critical species, those on Rubi, by the Rev. W. M. Rogers, occupying |