201 2 
ca R. indecora, Sprague.et Riley, comb. nov.—Oenothera indecora, 
amb 
R. ‘laciniata (Hill), Rose. 
R. littoralis (Schlecht.), Rose. 
. longiflora, Sprague et Riley, comb. nov.—Oenothera 
hongehrs Jacq. 
oa (A. Gray), R 
mendocinensis, Sprague at “Riley, comb. nov.—QVenothera 
mendocinensis, Gill. 
- mexicana (Spach), Woot. et Standley. 
ima, Sprague et Riley, comb. nov.—Oenothera 
mollissima, Linn 
octurna, Sprague et Riley, comb. nov.—Oenothera nocturna, 
ac 
R. odorata, Sprague et Riley, comb. nov.—Oenothera odorata, 
acq. 
R. Punae, Sprague et Riley, comb. nov.—Oenothera Punae, 
Kuntze. Oe. Mandoni, Léveillé. Oe. Kuntziana, Léveillé. 
R. rhombipetala (Nuit.), Rose. 
SPECIES EXCLUDENDA. 
R. coronopifolia, Rose = Anogra coronopifolia, Britton. 
XXIII. THE GENUS THERORHODION. 
J. HouTcHInson. 
For some time the writer has held the opinion that the 
curious and rare plant met with in a few of our gardens under 
the name Rhododendron camtschaticum,* Pall., would be better 
regarded as a separate genus from Rhododendron proper. This 
treatment has been accorded it by Mr. J. K. Small i in the North 
American Flora, vol. 29, pt. i, p. 45 (1914), wherein Maximowicz’s 
section Therorhodion is” raised to generic rank. Mr. Small 
describes a new species, “ Therorhodion glandulosum, Standley,” 
from near Port Clarence, Alaska, distinguished from 7'. camt- 
schaticum by its leaves being glandular-ciliate and its glabrous 
corolla with relatively longer lobes than tube. This species is 
not so far represented in our collections at Kew. To these two 
species should be added a third, Therorhodion Redowskianum, 
Hutchinson, a Manchurian plant described by oe as 
Rhododendron Redowskianum. This species has c 
botanical history. As far back as 1826, in the first volume 
of “‘ Linnaea”’ (p. 513), it was identified by Chamisso an 
Schlechtendal with a European plant, Rhodothamnus Chamae- 
* This is the ——— spelling; later authors have generally spelled 
it kamtschaticum 
