BALFOUR—NEW SPECIES OF RHODODENDRON. 53 
Rh. neriiflorum. It is not rash to expect that further explora- 
tion of this extreme west boundary of Yunnan will bring to 
light other allied species. 
Rh. neriiflorum and this new species Rh. dimitrum do not 
leave us in doubt about their affinity. They belong to a large 
group of species with beautiful flowers that includes the 
Forrestii series, the Sanguineum series, and the Haematodes 
series. Their characters which entitle them to rank as a series 
and to be spoken of as the Neriiflorum series alongside of those 
mentioned are the great reduction of the under-leaf indumentum 
—restricted to a floccose covering of the midrib—and the great 
development of the calyx. The large group embracing all these 
series and perhaps others may be looked upon as one parallel 
with but differing from that of Thomsoni, to which I have 
referred elsewhere.* 
Rh. neriiflorum has been in cultivation for some years— 
introduced in 1910 by Bees, Ltd., through seed collected by 
Forrest,— and has flowered freely. Of itself a charming 
plant it will be doubtless the parent of many hybrids in our 
gardens. No artificial hybrids of flowering age have yet been 
raised in cultivation, but two distinct remarkable plants have 
appeared in gardens—one with Mr. J. C. Williams at Caerhays, 
the other with Mr. Magor at Lamellen,—which it has been 
suggested may be natural hybrids that have sprung from seed 
introduced with the seeds of one of their respective parents. 
To these reference must be made here. 
In spring of 1918 Mr. J. C. Williams sent to me a truss of 
a ‘“‘rogue’’ of which several individuals had appeared amongst 
his plants of Rh. callimorphum, Balf. f. et W. W. Sm. This 
rogue - plant has flower - characters resembling those of Rh. 
nertifiorum, and vegetative characters belonging to Rh. calli- 
morphum. The flowers are smaller than those of Rh. neriiflorum. 
The calyx shows the unequal large-fringed lobes and the same 
splitting in front as we find in Rh. neriiflorum, but both calyx 
and corolla are spotted with crimson, and this is unknown in 
Rh. neriiflorum. The ovary is more truncate at the top, and 
the style is glabrous, not floccose, at the base. The flower is 
altogether different from that of Rh. callimorphum, where the 
pedicels are glandular not floccose, the calyx minute, corolla. 
openly campanulate and rose-coloured, and the ovary is glandular, 
as is the base of the style. The vegetative character in which 
the rogue resembles Rh. callimorphum and differs altogether from 
Rh. neriiflorum is the setulose-glandular surface of the young 
stems of the petioles and of the lamina of the young leaves. 
The setae are not very long, but densely clothe the parts. In 
* See Notes, R.B.G., Edin., x (1917), 98. 
