Darwinianprinted version  ISSN 0011-6793

Vol.46 no.2 Darwinian San Isidro Aug. / Dec. 2008

 

SYSTEMATICS AND TAXONOMY OF VASCULAR PLANTS

District of Rebutia Minuscula (Cactaceae, Cactoideae)

Nora B. Muruaga 1 , Mary R. Romero Figueroa ? & Roberto Kiesling2

¹ Miguel Lillo Foundation, Laboratory of Plant Taxonomy Fanerogámica, Miguel Lillo 251, 4000, Tucumán, Argentina; nmuruaga@yahoo.com.ar (corresponding author). ² IADIZA. Argentine Institute for Arid Zones, Mendoza, Argentina.

Original received on 7 April 2006, accepted on April 4, 2008

Summary.

Species Rebutia distributed from northwestern Argentina to southern Bolivia (Cochabamba to Tarija). Five species growing in Argentina, including the type species of the genus: R. lowercase. Phenotypic diversity, very common within species Rebutia, has led to the publication of numerous specific and infraspecific names, producing a real confusion in the nomenclature and synonymy distinctness of species, particularly R .lowercase, which overlaps the boundary of R. wessneriana. The purpose of this study was to reevaluate the definition of R.lowercase. 's exo-micromorphological characteristics of natural populations inhabiting the upper montane forest and high pastures of the provinces of Catamarca, Tucumán, Salta and Jujuy were analyzed. The data were documented with illustrations and photographs, information of geographical distribution, ecological and phenological observations is provided. Includes synonyms and nomenclatural types for some of them are designated. Is considered to R. wessneriana as a subspecies of R. lowercase and proposes a new combination and a new range for naming: Rebutia lowercase subsp. wessneriana.

Keywords . Argentina; Cactaceae; Cactoideae; Rebutia; Taxonomy.

Abstract . circumscription of Rebutia lowercase (Cactaceae, Cactoideae).

Species of Rebutia are distributed from northwestern Argentina to southern Bolivia (Cochabamba to Tarija). Five species grow in Argentina, including the type species of the genus: R. lowercase. phenotypic The diversity, very varying Within the species of Rebutia, Promoted publication of the multitude numerous specific and infraspecific names, leading to significant confusion in nomenclature, synonymy, and distinctive characters of its species, Particularly for R. lowercase, Whose delimitation overlaps With That of R. wessneriana. The aim of this work is to reevaluate the circumscription of R. lowercase. Exo-micromorphological Characteristics of Natural Populations growing in the upper mountain forest and highgrasslands of Catamarca, Tucumán, Salta and Jujuy provinces, Were analyzed. Data Were documented with illustrations and photographs; geographic distribution of information is provided as well as ecological and phenological observations. Synonyms are included and the nomenclatural types for some of them are established. Rebutia wessneriana is Considered as subspecies of R. lowercase and a new combination and a new rank is Proposed: Rebutia lowercase subsp. wessneriana.

Keywords . Argentina; Cactaceae; Cactoideae; Rebutia; Taxonomy.

INTRODUCTION

Rebutia lowercase K. Schum. is the type of the genus and one of the five cited by Kiesling (1999) for Argentina species. It presents a great variability in their habit, shape and size of the stem, dis position of their hubs, number, length and color of the thorns, so does the color of its flowers between red and orange and the arrangement of flowers along the stem. The areolas floral ornamentation, presence or absence of hairs and bristles, and the degree of welding of style with the floral tube, are also variable traits within the species, which can be interpreted in different ways. Buxbaum (1953) mentions that in R. lowercase floral areolas have hairs or bristles and the floral tube is welded to the base of the style. In contrast, and using that name in a broader sense, Hjertson (2005) distinguishes R. lowercase , among other characters, by having floral areolas hairy, with or without bristles and "solid floral tube", ie, style, partly welded to the tube. Moreover, Hjertson (2005) recognizes R. wessneriana Bewer. as a synonym of R. lowercase characters but does not specify that it is based to synonymy, whereas Kiesling (1999) treated R. wessneriana as a synonym of R. marsoneri Werderm,. throughout the previous literature R. wessneriana and R. lowercase are treated as different species, mainly by the soldier style floral tube flower larger and more intense red in R. wessnerianaand freestyle in R. lowercase . The purpose of this research was to circumscribe R. lowercase based on the exomicromorfológicas characteristics presented in their natural habitat, and discuss its relationship with R. wess-neriana . The characteristics studied are documented with illustrations and photographs, geographic distribution information is provided both altitudinal and latitudinal, ecological and phenological observations.

MATERIALS AND METHODS

A comprehensive assessment of the exo-micromorphological characteristics in natural populations in the upper montane forest and high pastures of the provinces of Catamarca, Tucumán, Salta and Jujuy was performed. Original descriptions and herbarium specimens available in BAB, CTES, LIL, SI, SGO (Holmgren et al., 1990) were analyzed. Pollen and seed materials come from samples collected from their habitat. Pollen grains were acetolyzed according technique Erdt-man (1960) and mounted in glicerinagelatina. The observations were made with an optical microscope (OM) Wild. For analysis of sculpture exine material not acetolizado was used metallized do with gold vapor and microfotogra-rays were obtained with a scanning electron microscope (SEM) Jeol 35 CF Service Electron Microscopy, National University of Tucumán . to observe seed SEM, washed repeatedly with distilled water and mounted in synthetic enamel specimen holder and coated with gold vapor, then photomicrographs were obtained with the same scanning electron microscope (SEM). For descriptions of the terminology seeds Barthlott & Hunt (2000) was followed.

RESULTS AND CONCLUSIONS

Rebutia wessneriana shares with R. lowercase the following morphological features: simple, globose stem, globosodeprimido to cylindrical, sometimes clavate, then pendulum always mamelons tetrahexagonal base; numerous spines (-30), straight and usually weak, lateral flowers, small, 5 ( -6) cm long, infundibular, long, narrow tube, red to orange,. stamens numerous spirally arranged along the floral tube, partially welded to the floral tube at its base, then freestyle; floral areolas almost all glabrous; a Sometimes, some of the basal pericarpelo have a few hairs and bristles. Both entities pollen is similar: isopolar, lobed-fosaperturado, tricolpate; exine (SEM) puntitegilada with scattered spinules and perforations ( Figs 1. , and 2 ).

 Fig 1. bean pollen R. lowercase subsp. wessne-Saharan Africa . A, polar view. B, equatorial

view. C, detail of exine (of 390 Muruaga, LIL).

 Figure 2. Pollen Grain R. lowercase subsp. lowercase . A, equatorial view. B, detail of exine

(of 298 Muruaga , LIL).

The seeds in both taxa are oval, small (0.8-1.2 mm long.), Brilliant black, the head cells are generally isodiametric, tetragonal to hexagonal, with limit anticlinal ribbed, straight and well intracellular gap differentiated and embossed convex; testa cells seed apex shaped projections have acuminata or are truncated and the side of lower dome shaped cones, gradually become smaller in the edge region hilomicropilar; which is oblique and large ( Figs 3.and 4 ).

 Figure 3. seed R. lowercase subsp. lowercase . A, detail of testa cells of the apex of the

seed. B, testa cells of striated anticlinal walls ( Muruaga 298, LIL).

 Figure 4. seed R. lowercase subsp. wessneriana . A, detail of apex cells of the seed. B cells

testa smooth anticlinal walls (Muruaga 390 , LIL).

These data indicate that R. lowercase and R. wessneriana share most morphological characteristics and is therefore difficult to draw boundaries between them. We also note that in R. lowercase and R. wessnerianastyle floral tube and soldiers are always greater or lesser extent, and both flower size and color are not enough to keep them as distinct species, as these characters vary in natural populations. Furthermore, analysis of pollen grains and seeds reinforce the similarities between the two taxa tudes. However, R. lowercase and R.wessneriana differ in the degree of welding floral tube, in the ornamentation of the anticlinal cell walls of the seed coat in the geographical distribution and, hence, we consider that there are two distinct species, but R.wessneriana is a subspecies of R. lower case , on the basis of differential characters you can see in the Table 1 .

Table 1. Differences between subspecies of Rebutia lowercase. 

Moreover, R. marsoneri differs from R. lowercase for having a depressed-globose stem to 4 cm diam., areolas with 9-15 spines 3-5 mm long. and red or yellow flowers.

TAXONOMIC TREATMENT

Rebutia lowercase K. Schum., Monatsschr. Kakteenk. 5 (7): 102. 1895. Echinopsis minus culaFAC Weber in Bois, Dict. Hort. 1: 471. 1896. Echinocactus minusculus FAC Weber in Bois, Dict.Hort. 1: 467. 1896. TYPE: sn icon in Schumann, Monatsschr. Kakteenk. 5 (7): 102. 1895, reproduced by Schumann in Gesamtb. Kakteen: 395, fig. 67. 1898 (lectotype been appointed by M. Hjertson, Cact Init Syst 19:.... 20 2005). Fig.   Six  .

Figure 5. flower detail. A, R. lowercase subsp. lowercase (for Muruaga 298 , LIL). B, R. lowercase subsp. wessne-Saharan (of 390 Muruaga , LIL).

 Fig 6. Rebutia lowercase subsp. lowercase . A, general

appearance. B, areola. C, flower. D, longitudinal section of flower and detail of the insertion of the filaments. E, abaxial view of a flake floral pericarpelo where the areola is observed with

some hairs. F, fruit. G,seed (of 298 Muruaga , LIL).

Stems usually solitary, globose-depressed to cylindrical, 1-14 cm long. x 2-8 cm diam., exceptionally clavate, then pendulums up to 20 (-40) cm long., olivaceous-green to green. Hubs base tetra arranged in a hexagonal spiral. Thorns (10 -) 25 (-30) or whitish tip and chestnut, dark yellow or brown basis up to 25 mm long, straight and generally weak.. Numerous flowers (± 15 simultaneous), 3-5 (-6) cm long. x (2 -). 3-4 cm diam, laterally located in the stem, never apical infundibular completely red, sometimes red-blood, or the yellow receptacle basal, middle or upper portion and red perigonio Brown reddish-violet to orange or pink. Numerous stamens (± 63), with yellowish-white or pink filaments arranged spirally along the floral tube ± 14 mm long. Style white to reddish; whitish stigma. The floral Areolas usually glabrous receptacle, sometimes some baseline pericarpelo tube and with few short hairs, with 1-5 (-10) bristles or without. Fruit globose to subglobose,

sometimes pyriform, greenish, yellowish to reddish pink, triangular to broadly triangular scales of ca. 2mm long. x 1 mm lat., somewhat fleshy at the base and membranous at the apex, glabrous or glabrescent. Seeds numerous, generally small 0.8-1.2 mm long, shiny black testa,. Testa cells at the apex of the seed-truncated conical projections or conical acuminate that you have roughly grouped into a ridge or are scattered.

Key to the subspecies of Rebutia lowercase

1. Style welded on (1 -) 3 mm long. the floral tube at its base. Seeds with testa cells of striated anticlinal walls. Dispatched from Jujuy Catamarca up ............ 1a. R. lowercase subsp. minuscule 1. Style soldier in 7 (-10) mm long. the floral tube at its base. Seeds with testa cells smooth anticlinal walls. It lives in the town of Volcan, Jujuy Province ....... 1b. R. lowercase subsp. wessneriana

1a. Lowercase R. K. Schum. subsp. lowercase

Rebutia senilis Backeb, Freund Kakteen-1 (11). 124. sn 1932 fig. TYPE: sn icon in Backeberg, KakteenFreund 1 (11): 124. 1932 (seen lectoti-po appointed by M. Hjertson, Cact Init Syst 19:... 21 2005.).

Rebutia senilis var. hyalacantha Backeb, Freund Kakte-in-1 (12). 131. 1932. TYPE: Argentina, Salta, Chicoana, Escoipe Gorge, 1600 m sm, 15-IX-2005, NB 404 Muruaga (LIL neotype here designated).

Rebutia senilis var. stuemeri Backeb, Freund Kakteen-1 (12). 131. fig. sn 1932. TYPE: sn icon in Backeberg, Kakteen-Freund. 1 (12): 131. 1932 (lectotype here designated).

Rebutia xanthocarpa Backeb, Freund Kakteen-1 (12). 131. fig. sn 1932. TYPE: sn icon in Backeberg, Freund Kakteen-1 (12): 131. 1932 (lectotype been appointed by M. Hjertson, Cact Syst Init:... 19: 22 2005.).

Rebutia dasyphrissa Werderm., in Fedde, Repert. Spec. Nov. Regni Veg. Sonderbeih. C. t. 103.1935. Rebutia xanthocarpa var. dasyphrissa (Werderm.) Backeb., Beitr. Sukkulentenk.Sukkulentenpflege: 3. 1939. TYPE: sn icon in Werdermann, bluh. And kakteen. Sukk. Pflanzen 26: t. 103. 1935 (lectotype here designated).

Rebutia violaciflora Backeb., Blatt. Kakteenf. (Unnumbered) 8. 1935. fig. sn 1935. Rebutia lowercase K. Schum. . subsp violaciflora (Backeb.) Donald, Ashingtonia 2 (3): 43. 1975. TYPE: sn icon in Backeberg Blatt. Kakteenf. (Unnumbered) 8. 1935 (lectotype here designated).

Rebutia chrysacantha Backeb in Backeberg & Knuth, Kaktus-ABC. 276, 416. "1935", 1936.Rebutia senilis Backeb. subsp. chrysacantha (Backeb.) Donald, Ashingtonia 2 (3): 50. 1975.TYPE: Argentina, Jujuy, El Carmen, Abra Santa Laura, 1336 m sm 3-XII-2004, NB 391 Muruaga(LIL neotype here designated).

Rebutia grandiflora Backeb in Backeberg & Knuth, Kaktus-ABC. 277, 416. "1935", 1936. Rebutia lowercase var. grandiflora (Backeb.) Krainz in Krainz, Die Kakteen, 15.VII.1960. CVC. (No pagination, sub R. lowercase var. grandiflora ). Rebutia lowercase subsp. grandiflora (Backeb.) Donald, Ashingtonia 2 (3): 43. 1975. TYPE: Argentina, Salta, Chicoana, Quebrada Escoipe 12-XI-1995, R. Kiesling et al. 8723 (SI neotype here designated).

Rebutia knuthiana Backeb in Backeberg & Knuth, Kaktus-ABC. 277, 416. "1935", 1936. Rebutia violaciflora var. knuthiana (Backeb.) Donald, Nat Cat Succ. J. 12: 11. 1957. TYPE: Argentina, Salta, Rosario de Lerma, Campo Quijano, 18-XI-1942, A. Burkart 13162 (SI neotype here designated).

Rebutia senilis Backeb. var. aurescens Backeb in Backeberg & Knuth, Kaktus-ABC. 278, 416."1935", 1936. TYPE: Argentina, Salta, Chicoana, El Rodeo, before The Trench, 2300 m sm, 16-IX-2004, NB 385 Muruaga (LIL neotype here designated).

Rebutia senilis Backeb. var. lilacinorosea Backeb in Backeberg & Knuth, Kaktus-ABC. 416."1935", 1936. TYPE: Argentina, Salta, Chicoana, 22 Km west of El Carril, 2770 m sm, 10-X-2004,NB 386 Muruaga (LIL neotype here designated).

Rebutia xanthocarpa Backeb. var. citricicarpa Fric ex Backeb., Cact. Succ. J. (U.S.) 23 (3): 83.1951. TYPE: Argentina, Salta, La Caldera, from Yacones to Potrero de Castilla, 1800 m sm, 14-IX-2004, M. Cecotti & NB 383-ga Murua (LIL neotype here designated).

Rebutia xanthocarpa Backeb. var. elegans Backeb., Cact. Succ. J. (U.S.) 23 (3): 83. 1951.Rebutia chrysacantha var. elegans (Backeb.) Backeb. Die Cactaceae 3: 1539. 1959. TYPE: Argentina, Tucuman, Trancas, San Pedro de Colalao, 1500 m sm, XI-1933, CR 9742 Schreiter(LIL neotype here designated).

Rebutia xanthocarpa Backeb. var. luteirosea Backeb., Cact. Succ. J (U.S.) 23 (3): 83. 1951.TYPE: Argentina, Salta, Guachipas, Torino, 1100 m sm, 14-IX-2005, NB 402 Muruaga (LIL neotype here designated).

Rebutia xanthocarpa Backeb. var. salmonea Fric ex Backeb., Cact. Succ. J. (U.S.) 23 (3): 83.1951. TYPE: Argentina, Tucuman Tafi Viejo, Cumbres del Cerro Cabra low Horco, 1900 m sm, 17-IX-1999, NB 324 Muruaga (LIL neotype here designated).

Rebutia senilis Backeb. var. schieliana Bewer., Kakt. And. Sukk. 8 (7): 105. fig. sn 1957. TYPE: sn icon in Bewerunge, Kakt. And. Sukk. 8 (7): 105. 1957 (lectotype here designated).

Style floral tube welded to the base to 3 mm long., Then free ca. 33 mm long., Whitish. Seeds with testa cells of striated anticlinal walls.

Geographic distribution and habitat . Schumann (1895) mentioned that R. lowercase probably came from Argentina, according to information received from Mr. Pierre Rebut, French time grower who is dedicated the genus name.

Subsequently Weber (1896) Quote for the province of Tucumán and Schumann (1898) repeats the town of Weber, who quite possibly got the plants directly from F. Schickendantz of Tucumán. Spegazzini (1905) Quote for Tucuman and Salta, like Kiesling (1999). campaigns conducted in northwestern Argentina ratify its allowed range for the provinces of Tucuman and Salta, Jujuy expand its presence where the but under other names known as the province of Catamarca, where there had been summoned. grows in rock crevices exposed upper montane forest in rocky or hilly relief sites in grassland environment, between 1100-2800 m sm is a component of the stratum herbaceous and grows with Viguiera tucumanensis(Hook. & Arn.) Griseb. var. oligodonta (Blake) Cabrera, Stevia yaconensis Hieron., Tagetes terniflora Kunth,Ipomoea rubriflora O'Donnell and Lamprothyrsus hieronymi (Kuntze) Pilg., among other species.

Phenology . Both cultured and wild stocks of different species of the material, it was observed that R.lowercase begins to bloom in mid-August and flowers and fruits simultaneously. The period of greatest production of flowers and fruits is at the end of the dry season and beginning of the rainy season (October-November).

Anthropogenic factor . Collection sites generally do not show any significant alteration produced by man.However, as a result of livestock in some high mountain sites, dry grass burned in the months of September and October. This activity significantly affects populations living there.

Observations . In most cacti described based on a specimen grown herbarium materials or locations not mentioned, but the names are valid through 1957 were published (Greuter et al, 2000 Art.. 37.1), but several descriptions are accompanied by an illustration that the only existing original material observed by the author, have been designated as lectotypes here. Designate neotypes for taxa described before January 1, 1958 of Backeberg publications (in Cact. Succ. J. (U.S.) 23 (3), 1951) and Backeberg & Kunth (in Kaktus-ABC, "1935", 1936) was not designated as type material by the authors. Also, not to Bäckerberg herbarium specimens, so that almost all species published since 1958 are invalid.

While following synonyms were already established by other authors, we consider it appropriate to comment on our observations based on wild material: In Rebutia senilis specific epithet refers to the white color of the spines, a quality that is quite variable within a population. To our knowledge, this name was created for individuals who are depressed-globose stem 7 cm long. x 8 cm diam., completely covered with thorns about 2.5 cm long. Rebutia senilis var. stuemeri was created by Backeberg (1932) for their

flowers up to 4 cm long., red-tile inner tepals yellow to reddish white throat; these characters, highly variable within a population, are not sufficient to accept a variety within the species. Variety Rebutia senilis var. lilacinorosea is not accepted because the difference allocated in the color of the flower is not relevant and .'s color variations between the species having Backeberg & Knuth (1936) mention the presence of very thin, sharp, long and dense spines, yellow plants inRebutia senilis var. aurescens , these characters are highly variable within a population for which the assigned differences are not relevant. Rebutia grandiflora is distinguished, among other characters, by the size of the flower (6.5 cm long.) size we observed in individuals flowers locality El Rodeo, Apt. Chicoana, Province of Salta, corresponding to R.lowercase . 's name Rebutia xanthocarpa was based on the yellow color of the fruit, but this color is part of the variation that can be found in the fruits of the species. Rebutia xanthocarpa var. salmonea as its varietal epithet implies, I think for individuals with salmon flowers, varying in color in different individuals. Rebutia xanthocarpa var. elegans is characterized by long and wispy spiral spines and ribs. The length and consistency of the spines are variable characters within the group. Sometimes the hubs are arranged vertically aligned together giving the appearance of ribs. However, this feature is not constant within the species. 's name Rebutia chrysacantha was created for individuals who have the yellow gold spines. Observations in natural populations show that the color of the spines is variable and may be whitish, yellowish or dark brown. Backeberg (1977) quotes Rebutia violaciflora to northern Argentina, in Salta and in the upper part of the Gorge Escoipe. The material collected by us in flowers exhibit the same red-violet shades that this taxon is based, which are within the variation of colors presented floral species.

Representative material examined

ARGENTINA. Jujuy . Dept.. Dr. Manuel Belgrano, way Tiraxi 3-XI-1974, Schinini 10014 (SELV), from Laguna Tiraxi Treasurer, 1517 m sm, 16-IX-2005, 405 Muruaga (LIL). Tucuman . Dept..Trancas, Quebrada de la Hoyada, 1500 m sm, 26-XI-1920, Schreiter 66740 (LIL); Hualinchay, Quebrada Pozo del Rio Grande, 1500 m sm, 9-IX-1999, 298 Muruaga (LIL). Dept.. Tafi del Valle, Ñuñorco base of Cerro Grande, 2800 m sm, 17-IX-2000, Boero sn (LIL 605758). Catamarca.Department. Andalgalá The Banderita, 2000 m sm, 20-X-2001, 357 Muruaga (LIL).

1b. Rebutia lowercase K. Schum. subsp. wess-neriana (Bewer.) Muruaga, stat. & Comb. nov. Rebutia wessneriana Bewer. Sukkulentenkunde 2: 24. 1948. Rebutia krainziana Kesselr. var. wessneriana (Bewer.) Krainz & Haarm., Katalog. Städt Zürich. Sukk. Samml. Ed 2. 107. 1967. TYPE: sn icon in Bewerunge, Sukkulentenkunde 2: 24. 1948 (lectotype been appointed by M. Hjertson, Cact Init Syst 19:.... 21 2005).

Rebutia calliantha Bewer. Sukkulentenkunde 2: 25. 1948. Rebutia wessneriana Bewer. var. calliantha (Bewer.) Donald, Nat Cact. Succ. J. 14 (1):

5. 1959. TYPE: Argentina, Jujuy, "Volcano unten" F. Ritter 58 . Loc 2 (sa) (SGO-124559 neotype here designated).

Style floral tube welded to the base to 10 mm long., Free in ca. 12 mm long., White, red to pink. Seeds with testa cells smooth anticlinal walls. Geographical distribution and habitat. It lives in the town of Volcano, Province of Jujuy, and grows rooted in the clefts of the rocks on the rocky hillsides.

Observations . With no existing material on which the name of the original taxon was based Rebutia calliantha neotype is designated.

Representative material examined

ARGENTINA. Jujuy . Dept.. Tumbaya, Volcano, Laguna, 19-I-1998, Kiesling 8901 (SI), Volcano, 31-X-1974, MC-8 (BAB), Volcano, Laguna, 2092 m sm 11-X-2004, 390 Muruaga ( LIL).

Invalid Names

Rebutia hyalacantha (Backeb.) Backeb in Backeberg, Die Cactaceae 3:. 1551. 1959. nom. illeg.as superfluous, by including R. wessneriana between synonyms and therefore its type (Greuter et al., 2000. Art. 52.1). Rebutia permutata Heinrich in Backeberg, Descr. Cat Nov. 3: 13.1963. nom. inval. lack of mention of type item (Greuter et al., 2000. Art. 37.1). Rebutia wessneriana Bewer. . var permutata (Heinrich) Buining & Donald, succulenta 51 (12): 225, 1972. comb. inval. because its basionym is invalid. Rebutia xanthocarpa Backeb. var. violaciflora (Backeb.) Backeb in Backeberg, Descr. Cat Nov. 1: 31. 1956. nom. inval. lack of mention of the basionym (Greuter et al., 2000. Art. 33.3).

Acknowledgements

The authors thank the Fundación Miguel Lillo by the total support that has enabled this work to be carried out. Reviewers for their valuable suggestions, Mr. Alberto Gutierrez conducting sheets and the curators of the herbaria for the loan of the requested material.

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12 Schumann, KM 1898. Gesamtbeschreibung der Kakteen, Vlg. J. Neumann, Neudamm : 1-832. [  Links  ]

13 Spegazzini, C. 1905. Cactacearum Platensium Tentamen. Anales Mus. Buenos Aires Nat 11: 477-521. [  Links  ]

14 Weber, FAC 1896. Dictionnaire d'Horticulture , Bois (ed.). P. Klincksieck, Paris. [  Links  ]