30 
weeks earlier than those of the Catawbiense Hybrids. There is much 
confusion in regard to the history of many of these plants and their 
breeding. The most satisfactory of them here is called Boule de Neige. 
Judging by the name, it was raised in France or Belgium. Only the 
name appears in the most elaborate work on Rhododendrons which has 
been published, and nothing now appears to be known about its breed- 
ing. Boule de Neige has white flowers faintly tinged with pink when 
they first open and is one of the best Rhododendrons which can be 
planted in New England. The Arboretum will be glad of information 
about its history. Other good plants here of the Caucasian race are Mont 
Blanc, with deep rose-colored flower-buds and expanding flowers which 
soon become pure white. This is a taller and not as wide-spreading a 
plant as Boule de Neige. Sultana and Cassiope are dwarf white-flow- 
ered plants of less vigorous growth and dwarfer habit than Mont Blanc. 
A plant of R. coriaceum, not rare in English nurseries, has been in the 
Arboretum for many years, and although it flowers a week or two later 
than the plants already mentioned it appears to be of Caucasian blood. 
R. venosum with bright rose-colored flowers, usually found in nurseries 
under the erroneous name of R. Jacksonii, is a hybrid of R. caucosi- 
cum, and R. arboreum raised in England in 1829. It is highly thought 
of in England, where it has been much planted, but in the Arboretum 
is less hardy .than the other Caucasian hybrids. A plant which has been 
growing in Mr. HunnewelTs garden at Wellesley for at least fifty years 
is evidently a hybrid of R. caucasicum. The original specimens were 
imported from England and are now round-topped bushes about six feet 
high. For at least thirty years they have never suffered from heat or 
cold, and have never failed to flower freely. The leaves show the in- 
fluence of R. catawbiense, but the size of the flower-clusters point to 
R. caucasicum. The early flowers, for this is one of the earliest of 
the hardy Rhododendrons to bloom in this climate, show also the cau- 
casicum influence. Whatever its name or parentage this is a valuable 
plant, for it is certainly one of the hardiest hybrid Rhododendrons 
which have been planted in this country. In the Arboretum collection 
there are only small specimens. 
In England several hybrids of Rhododendron Smirnoivii have been 
raised. Some of these which originated at Kew have been tried in 
the Arboretum but without much success. Of more promise are a 
number of plants raised at Holm Lea by Charles Sander by crossing 
R. Smirnowii with a Catawbiense Hybrid. They have now flowered in 
the open ground for several years and appear perfectly hardy. The 
flowers are large, in large compact clusters and vary from clear pink 
to deep rose color. The leaves are longer than those of either parent, 
but are without a trace of the felt which covers the lower side of the 
leaves of R. Smirnowii. We have here perhaps an early-flowering race 
which may add greatly to the possibilities of Rhododendron cultivation 
in this country. 
By crossing Rhododendron Fortunei from southern China with some 
of the Indian species some of the handsomest of all Rhododendrons 
have been obtained in English gardens. These are not hardy in this 
climate, but hybrids of R. Fortunei, crossed probably with hybrid Cataw- 
