BALFOUR—NEW SPECIES OF RHODODENDRON. I7I 
studied for prescription of limitation. When describing Rh. 
eudoxum 1 placed it as an aberrant form of the Sanguineum 
series. When describing Rh. temenium I emphasised its relation- 
' ship to Rh. neriiflorum. In Rh. pothinum and Rh. trichomiscum 
we have now two new forms which add to our data for framing 
phyletic lines, but Iam not to discuss them in detail here. There 
is still a mass of related material of Forrest’s collecting that 
requires analysis before sound deductions are possible. I will 
only say that these new species are closely allied to the forms 
already known and show the same character intermediate to 
Rh. sanguineum on the one side and Rh. neriiflorum on the 
other. The prominent character of relation—one which appears 
at sight—is that of the underleaf indumentum which in RA. 
eudoxum is a thin white veil of interwoven floccose hairs—only 
requiring thickening to represent fairly well a typical Sanguineum 
series indumentum—which is more or less detersile and in RA. 
pothinum is absent altogether from the first and so we are taken 
to Rh. neriiflorum.* Additional material which has reached 
us from Forrest since the date of my previous writing on this 
subject enables me to establish as a character possessed by all of 
the four species here mentioned the development of bristles on 
the young stems, leaf-petioles, and even on the lamina-bases. 
These bristles sometimes disappear early: and this explains 
omission of mention of them in the description of Rh. eudoxum. 
In that species as in the others they occur. In a key which I 
framed of diagnostic marks between some of the members of 
the Sanguineum series,} Rh. eudoxum is included and occupies 
an isolated position, and to shorten my writing the following 
extension of that portion of the key which refers to Rh. eudoxum 
will suffice to bring out the relation between it and its three 
allies of which we"have been speaking, and with which it forms 
without question a subsidiary phylum between that of Rh. 
sanguineum and that of Rh. neriiflorum :— 
Underleaf surface grey-green, glabrou 
Scale-leaves of the bud falling at cena 
. Stems, ohne sig midrib in part ped sctnlose 
Pedicels and oats “densely fasciate-floccose 
landular. 
Calyx 3m mm. long ; cup and lobes pap 
n ba na lobes deep red floccose 
ersisten 
Corolla eran seine dark rose unspotted. 
Staminal filaments glabrou : 
Style shorter than corolla . pothinum. 
* See Notes R.B.G. Edin., xi (1919), pp. 76, 123. 
+ Ibid., 80 
