The Botany of Iceland - 01.12.1942, Blaðsíða 44
270
M. P. GHRISTIANSEN
T. declive seems to be closely related to T. subreduncum and T. sagittifrons, but
differs from these species especially by its dark-green outer bracts, dark grey-green
leaves and strongly spinous fruits. T. devexum which also has dark-green outer bracts
has the fruits spinous only above.
Habitat: Home-field.
Localities: ísafjörður, 12.VII.1935, fr., phot. N.W.
Geogr. Distr.: Only found in Iceland.
22. Taraxacum acutatum M.P.Chr. n. sp.
Spec. orig.: Iceland, Stórólfshvoll, 9.VII.1937, leg. M. P. Christiansen. Plate II,
fig. 22. Plate XII, fig. 120.
Planta 15—25 cm alta. Folia saturate viridia—sat cano-viridia, sat dense araneosa,
lingulato-lanceolata, integra et dentata—breviter 3—4-loba, petiolis sublatis—angustis,
pallidis—paulo roseis, nervo mediano lucide sed laete purpureo, lobis approximatis,
perlatis, brevibus, in apicem + reflexum, subulato-acuminatum abeuntibus, praesertim
inferioribus valde subulato-dentatis, superioribus antice + sigmoideis, lobo terminali
ovato-sagittato—cordato-hastato, acuto, 1—2-dentato, lobulis basalibus acutis.
Scapi + colorati, parce araneosi.
Involucrum basi turbinatum. Squamae exteriores adpressae, 4—2 X 10—12 mm,
ovatae—ovato-lanceolatae, apice breviter attenuatae, subtus olivaceo—virides, haud
vel angustissime albido-marginatae, ecorniculatae, supra glaucescentes.
Calathium c. 40 mm latum, planum, subdensum. Ligulae marginales c. 14 mm
longae, c. 3.5 mm latae, subtus stria grisea—paulo purpurea notatae, dentibus
brevibus, latis, purpurascentibus.
Antherae polline carentes.
Stigmata lutea, subtus albido-pilosa.
Achenium dilute stramineum (c. 162), c. 3.6 mm longum, 1.1-—1.2 mm latum,
superne latissimum, crebre, minute, interdum longe spinulosum, ceterum laeve, in
pyramidem conicam—conico-cylindricam, 0.4—0.5 mm longam abiens. Rostrum
8—10 mm longum.
T. acutatum, in its habit and the shape of the fruit, closely resembles T. devexum
and similar species, but differs from them by the strongly acuminate—subulate end
of the lobes, its lighter green leaves and more purple-coloured midnerve.
It is no doubt spontaneous.
Habitat: Mó, meadows.
Localities: Stórólfshvoll, 9.VII.1937, fr., phot., plentiful, Laugarvatn, 11.VII.
1937. S.
Geogr. Distr.: Only found in Iceland.
23. Taraxacum devexum M.P.Chr. n. sp.
Spec. orig. : Iceland, Þingvellir, 7.VII.1935, leg. M. P. Christiansen. Plate II,
fig. 23. Plate XV, fig. 130.
Planta 20—30 cm alta. Folia sat obscure—obscure viridia, parce araneosa, lingu-
lata—anguste lanceolata, regulariter 4—5-loba, petiolis pallidis, nervo mediano +
rubescenti, lobis basin versus latis, deltoideis, sensim acuminatis, saepe valde reflexis,
superioribus interdum hamatis vel in apicem + angustum, acutum abeuntibus, lobo
terminali longo, sagittato, acuminato, interdum + cordato et mucronato. Fol.
interiorum lobis in apicem + patentem abeuntibus.
Involucrum obscure olivaceo-viride.