The Botany of Iceland - 01.12.1942, Qupperneq 46

272
M. P. CHRISTIANSEN
24. Taraxacum perdevexum M.P.Chr. n. sp.
Spec. orig.: Iceland, Reykjavík, 6.VII.1935, leg. M. P. Christiansen. Plate II,
fig. 24. Plate XXII, fig. 150.
Planta sat gracilis, 15—25 cm alta. Folia obscure viridia, sat dense araneosa,
anguste lanceolata, regulariter 3—5-loba, petiolis sat latis, pallidis, nervo mediano
praesertim ad medium dorso + brunneo-rubescenti, lobis approximatis, basin versus
latis, deltoideis, acuminatis—subulatis, saepe valde reflexis, integris—inferioribus
denticulatis, lobo terminali sat longo, sagittato, integro, acuto, lobulis basalibus
subulatis.
Scapi folia superantes, pallidi— + colorati, parce araneosi.
Involucrum dilute viride. Squamae exteriores angustae, 1.0—1.5 mm latae,
adpressae—erecto-adpressae, subtus laete olivaceo-virides, claro- vel albido-marginatae,
apice + purpureo, supra laete virides.
Calathium c. 25 mm latum, densum, obscure luteum. Ligulae marginales c. 3 mm
latae, subtus stria obscure purpurea notatae, dentibus purpurascentibus.
Antherae polline carentes (vel parce polliniferae).
Stigmata luteo-viridia, extus obscura.
Achenium dilute stramineum (162), 3.0—3.5 mm longum, c. 1 mm latum,
superne latissimum, crebre et acute, interdum longe spinulosum, ceterum laeve—
+ tuberculatum, in pyramidem late conicam, c. 0.4 mm longam sensim abiens.
Rostrum 7—8 mm longum.
T. perdevexum has dark-green, narrow leaves with strongly reflexed, deltoid,
acuminate lobes, a long, sagittate terminal lobe and narrow, + appressed outer
bracts. The leaves are very like those of T. pergracile; but the latter has a fruit
with a long, narrow, cylindrical pyramid. See also T. devexum.—The species was
cultivated in my garden and differs strongly from all other Icelandic species.
It is no doubt spontaneous.
Habitat: Home-fields, mó, meadows, ditches.
Localities: Stórólfshvoll, 9.VII.1937. S.-—Rcykjavik, 6.VII.1935, fr., phot.,
plentiful, Laugarna at Reykjavík, 9.VII.1935, Þrastarlundur, 10.VII.1937. S.W.—
Stykkishólmur, 10.VII.1935. W.—Bilðudalur, 11.VII.1935, Flateyri in önundar-
fjörður, l.VIII.1937. N.W.
Geogr. Distr.: Only found in Iceland.
25. Taraxacum subscolopendricum M.P.Chr. n. sp.
Spec. orig.: Iceland, heath near Þingvellir, 30.VI.1937, leg. M. P. Christiansen.
Plate II, fig. 25. Plate XXVI, fig. 164.
Planta parva. Folia lingulata, saturate viridia, glabra—parce araneosa, parum
profunde lobata, petiolis late alatis, pallidis, nervo mediano pallido—paulo colorato,
lobis lateralibus 2—3 utrinque (in speciminibus cultis 3—-5 utrinque), approximatis,
late deltoideis, reflexis, acuminatis, superioribus integris, inferioribus + subulato-
dentatis, fol. interiorum magis dentatis, lobo terminali sat brevi—mediocri, triangulari
—ovato-sagittato.
Involucrum olivaceo-viride. Squamae exteriores ovatae—lanceolatae, + adpressae,
2.0—2.5(—3) mm latae, 5—6 mm longae, subtus olivaceo-virides, saepe late albido-
marginatae, supra laete virides.
Calathium c. 30 mm latum, planum, sat radians, laete luteum, ligulae marginales
planae, c. 3 mm latae, subtus stria lata, cano-violacea notatae.
Antherae polline carentes.
Stigmata virescentia—atro-virescentia.
Achenium stramineum (162), c. 3.9 mm longum, c. 1.3 mm latum, superne