62 JOUENAL OF THE KOYAL HORTICULTURAL SOCIETY. 
OBSERVATIONS ON SO^[E PLANTS EXHIBITED. 
By the Eev. Prof. G. Henslow, M.A., V.M.H. 
Delivered May 10, 1899.] 
Ceeasus pseudo-Cekasus, "James H. Yeitch." — This new importa- 
tion of Mr, Yeitch's is valuable, inasmuch as it is in full bloom three 
weeks later than the old one, and bears leaves simultaneously with the 
blossoms. It was introduced by Mr. J. H. Yeitch from Japan. 
Amherstia nobilis, a leguminous tree from the Malayan Peninsula, 
is remarkable for the distorted arrangement of its petals, the cause of 
which Mr. Henslow had previously explained in the case of other flowers 
in which it occurs (as the Horse-chestnut) ; viz. the visits of insects, 
which, resting on the stamens, cause them to become declinate, and by 
their searching for honey the petals have assumed irregular positions. 
Cleanthus puniceus, another plant of the Leguminosas, has peculiar 
flowers resembling the claw^ of a lobster. It is also called Parrot's-bill in 
New Zealand. It was introduced in 1831. Another species, C. Dampieri, 
is a native of desert regions of Australia. 
Alpine Plants. — Besides a selection of species with brilliantly 
coloured corollas, a peculiar Campanula, C. thyrsoides, was exhibited, a 
dwarf plant with small, densely compacted and greenish flowers. The 
native Primula auricula, and a much improved garden form, as well as 
the old-fashioned Centaurea montana, precisely like its present wild 
congeners of Alpine slopes, as about Muren, were taken as other represen- 
tations of the Swiss flora. 
Euphorbia. — A species with brightly coloured bracts— greenish-yellow 
— afforded material for observing the diversity of the powers of nature in 
constructing flowers. For instead of having a coloured corolla there was 
neither calyx nor petals, but only bracts ; w^hile the inflorescence, com- 
posed of a number of males represented by a single stamen apiece, 
surrounded one female flower consisting solely of a pistil of three coherent 
carpels. 
Dicentka, sometimes misspelt Dielytra, illustrated an ingenious appa- 
ratus for protecting the stamens and stigma by means of a cap which 
was hinged to the petals. This was pushed to one side when an insect 
visited the flower and exposed them, scattering the pollen thereby on to 
it, and so securing cross-fertilisation. 
Cut-leaved Elder. — A specimen of this afforded material for the 
explanation of the origin of compound leaves from single ones : by first 
making the blade lobed, then by separating the two lobes as leaflets, and 
by thus repeating the process, a trefoil, cinquefoil, or 7-leaflets might be 
obtained, as in Potcntilla reptans ; Blackberries and Raspberries illus- 
trating transitions from one to five leaflets to a leaf. 
Pelargonium, new Double. — A new double scarlet was shown in 
which the numerous petals were narrow. This feature is characteristic 
of tbe wild form with " windmill-sail " petals, and the peculiarity of the 
