The Botany of Iceland - 01.12.1942, Page 76

302
M. P. CHRISTIANSEN
Planta parva, 10—15 cm alta. Folia obscure- vel atro-viridia, brunnescentia, parce
crispa, sat dense araneosa, lingulato-lanceolata, integra et dentata—parum lobata,
petiolis alatis, purpureis, nervo medino fere ubique purpureo, lobis approximatis,
2— 3 utrinque, brevibus, deltoideis, patulis—hamatis, acutis, o—parce dentatis, lobo
terminali parvo-mediocri, ovato-sagittato—sagittato, obtuso—mucronato.
Involucrum basi sat turbinatum. Squamae exteriores erecto-patentes, lanceolatae,
3— 2 X 7—10 mm, subtus obscure olivaceo-virides, + obscure purpurascentes, supra
laete virides, + coloratae, interiores apice atro-purpureo.
Calathium c. 40 mm latum, planum, sat radians, obscure luteum, ligulae mar-
ginales subtus stria laete cano-rosea notatae, dentibus purpureis.
Antherae valde polliniferae.
Stigmata lutescentia—virescentia.
Achenium fusco-stramineum (162—153), c. 3.0—3.4 mm longum, c. 1.1 mm
latum, superne crebre et acute, incurvo-spinulosum, ceterum laeve—parce tubercula-
tum, in pyramidem latum, 0.3—0.5 mm longam, conicam abiens. Rostrum c. 9 mm
longum.
This very slender species recalls T. subeximium in the form of the fruit and the
colour and form of the leaves—especially in the cultivated herbs—but because of
its small size it cannot be mistaken for that species. On the other hand, it may be
confused with T. triste, which often has the same colour of leaves, the same size,
etc.; but in T. triste the fruit is fumished with long teeth and has a long, narrow,
cylindrical pyramid. It seems most closely related to T. ostrinum. On cultivation it
retained its small and slender habit, whereas offspring of T. ostrinum grew large
and robust.
It is spontaneous.
Habitat: Grassy spots in lava-field.
Localities: Skútustaðir at the south end af Mývatn, 28.VII.1935, fr., phot. N.
Geogr. Distr. : Only found in Iceland.
71. Taraxacum ostrinum M.P.Chr. n. sp.
Spec. orig.: Iceland, Vaglaskógur in Fnjóskadalur, 23.VII.1937, leg. M. P.
Christiansen. Plate VI, fig. 71. Plate XXIX, fig 173 and XXX, fig. 174.
Planta 15—25 cm alta, sat gracilis. Folia obscure viridia, fere glabra, longa,
leptalea, lingulata, integra et distanter dentata, dentibus 2—3 utrinque, brevibus,
hamatis, acutis vel anguste lanceolata, sat profunde lobata, petiolis alatis-—latis, +
purpureis, nervo mediano, praesertim eo fol. interiorum, ubique et lucide purpureo,
lobis 4—5 utrinque, sat patentibus, acutis, antice leviter concavis, denticulatis, lobo
terminali parvo, triangulari-hastato, integro vel uni-dentato.
Involucrum basi ovatum. Squamae exteriores 3.5—2.0 X 7—11 mm, erecto-
patentes, subtus olivaceo-virides, pruinosae, apice purpureo, subtus laete glaucescentes,
interiores apice atro-purpureo.
Calathium 40—50 mm latum, planum, valde radians, dilute—sat obscure luteum.
Ligulae marginales c. 2.8 mm latae, subtus stria cana vel cano-violacea notatae.
Antherae luteae, polliniferae.
Stigmata sat obscura—virescentia.
Achenium fusco-stramineum, c. 3.9 mm longum, c. 1.3 mm latum, superne dense,
breviter incurvo-spinulosum, ceterum tuberculatum—laeve, in pyramidem c. 0.6 mm
longam, late conicam sat sensim abiens. Rostrum 10—11 mm longum.
T. ostrinum has lingulate—lanceolate, entire—regularly lobed leaves with a
bright purple-coloured midnerve, somewhat dark, strongly radiating heads and broad
fruit with a broad conic pyramid like T. cordatifrons, a typical Eu-Spectabilia-íruit,
and the species is therefore classed with this group, although it differs very much