415 
leaves. The cause of the persistent bitter taste, possessed 
especially by P. Buchanani, Hook., P. eugenioides, A, Cunn., P. 
rhombifolium, A. Cunn., and P. undulatum, Vent., has not yet been 
investigated ; an alkaloid is only present in traces. Bullardiera 
longiflora, Labill., closely allied to Pittosporum also contains saponin. 
At Haarlem I found saponin a good many years ago in the leaves 
of Pittosporum Tobira, from the University Botanic Garden at 
Leiden. 
The fruits of P. phillyraeoides, DC., yielded an extract frothing 
at 1-4000 and haemolytic at 1-1500. The dry leaf of P. undu- 
latum, even gives an extract frothing at 1-1200, with haemolysis 
at 1—1500. 
The fairly common occurrence of saponin in this natural order 
has already been repeatedly remarked. Some species (P. coriaceum, 
Ait., P. viridiflorum, Sims), are even known as soap-substitutes in 
their native countries. The use of P. javanicum, Bl., as a fish 
poison doubtless also depends on the high saponin content of this 
plant. The saponin of P. undulatum, Vent., was examined in 
London in 1904 by Miss Hooper, and the essential oil in 1906 by 
Power (Pharm. Journ. 1904, 588 ; 1906, 755). 
Platanus (Platanaceae). 
In the spring of this year (1909) I first observed that the be 
foliage of the plane-tree undoubtedly contains hydrocyanic acid = - 
_ distilled it and converted it’ into Prussian blue. The jeune Be 
not large and when the leaves grow older the HCN content fa : 
off to small traces. The hydrocyanic acid is not a 
benzaldehyde, but probably with acetone. At Kewl . 9 ) 
analyse side by side four species of Platanus and to confirm all my 
o leaf: in P. cuneata, Willd., the largest amount wa 
found, i.e. about 0°05 per cent. Indeed, in the peang acai 
of the London streets (P. acerifolia), there 1s 80 — he Meare 
acid present that the amount from every London plane- 
be g. i ndon sparrow. 
cena ee pena was not known bag ods wil a, 
harmful property than that the bristly hairs of the fruit may , 
on inhalation the so-called plane-cough. 
Polemonium (Polemoniaceae). found to contain 
At Kew the leaves or F. epee re dine. 
Willd., P. or .. 
le, Willd.), an 
Wats., and P. Richardsonii, R. Srah. (= = ar lane i 
found that they all contain saponm, — in larg 
haemolysis with all species at about 1-300. been examined chemi- 
he ‘genus Polemonium has hitherto not : te taiied a 
cally, or hardly so, ‘The shoot of © a a Gureties 
antisyphilitic and the root of P. reptans, Li, % 
i e). . ‘cosa, Li. ? 
The lal oP dain et (i ey 
a plant from China, cultivated at Kew, “h 
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