THE ORCHID REVIEW. 329 
peared on two different occasions, is only known to me by description and 
a coloured figure. It originally appeared in the collection of M. Dallemagne, 
of Rambouillet, early in 1894, when it was described under the name of 
Odontoglossum X Impératrice de Russie. It is said to be intermediate 
between O. Hallii and O. Kegeljani, both in shape and colour. 
A little over a year later it appeared at L’Horticulture Internationale, 
Brussels, and was figured and again described as new, under the name of 
O. X Hallii-xanthum. It is said to have flowered out of an importation 
from Ecuador, and to be unmistakably intermediate between the two species 
above named. The sepals and petals are less acuminate than in O. Hallii, 
and the ground colour more yellow with fewer spots. In the details of the 
lip and column it approaches most nearly to O. Hallii. 
The following are the references :— 
Odontoglossum X Impératrice de Russie, L. Lind. in Journ, des Orch., 
I, Ps 360. 
O. X Hallii-xanthum, L. Lind. in Lindenia, x., p. 73, t- 467. 
So far as I am aware, no hybrid has yet appeared between O. cirrhosum 
and O. Kegeljani, though if the two species grow anywhere intermixed such 
a plant may some day occur. It is the only other possible combination 
between the four Ecuadorean species above mentioned. 
j R. A. ROLFE. 
St 
ONCIDIUM ONUSTUM. 
This extremely rare and very pretty Oncidium has just flowered in the 
collection of W. Thompson, Esq., Walton Grange, Stone. It has clear 
bright yellow flowers an inch in diameter, which are borne on an arching 
raceme about a foot long, the flowers being all turned to one side, some- 
what as in Rodriguezia secunda. It was originally described by Lindley in 
1833 from dried specimens collected by Cuming (Lindl. Gen. and Sp. Orch., 
p- 203), and on its appearance in cultivation in 1861, in the collection of 
Herr Borsig, at Moabit, near Berlin, was re-described by Reichenbach 
under the name of Oncidium holochrysum (Hamb. Gartenz., xvii. p. 33): 
Shortly afterwards Dr. Krause collected it for Messrs. Backhouse & Son in 
Ecuador, where it had previously been found by William Lobb. This is 
probably its native habitat, as, although Cuming’s specimens were localised 
Le PoAcins and Western Columbia,” it is known that some of his plants 
came from further south. It technically belongs to the section Equitantia, 
which is not well named, as the leavesof some species are not equitant. The 
column wings are falcate, erect, and longer than the column, and the crest 
of the lip broadly oblong, nearly flat, and with a couple of thin erect plates 
in front. It is very free flowering, and a really handsome little plant. 
