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and powerful odour of roses. Although the odour of roses (or 
geraniol) is not particularly rare among plants (the rose-like 
scent of young Willow foliage is well known and is especially 
noticeable in Salix babylonica, L., and S, elegantissima, C. Koch), 
know no other plant which has such an intense rose-scent as this 
Potentilla leaf. In the Jodrell laboratory I prepared from it an 
“aqua rosarum” of good quality. ‘The leaves of this species of 
Potentilla are said to be used in Russia instead of tea. 
Prosopis (Leguminosae-Mimoseae). : 
The leaf of P. juliflora, DC., contains saponin. An extract of 
the seeds only frothed at 1-200 and haemolysed at 1-125. 
The bark of Enterolobium cyclocarpum, Griseb., had already been 
noted as containing saponin. The pods of the species examined are 
considered poisonous to cattle. 
Protea (Proteaceae). 
The leaf of P. cynaroides, L., bruised with water, sets free a 
small quantity of hydrocyanic acid. In my second Kew report I 
hope to give further details about this plant. 
The natural order Proteaceae is still a “ terra incognita ” for the 
chemist. The case of Macadamia, mentioned in the present report, 
is evidently not an isolated one, and there is reason to suspect the 
presence of hydrocyanic acid in other genera also (e.g., Brabejum, 
Helicia). 
Psoralea ( Leguminosae-Papilionaceae). 
have examined the leaf of P. macrostachya, DC., at Kew and 
the seeds at Haarlem; both contained saponin, especially the leaf. 
any members of this suborder contain saponin. The root of 
P. glandulosa, 1, acts as an emetic and the leaves for instance are 
used as an anthelmintic. P. tenuiflora, Pursh., is regarded as 
poisonous and is avoided by cattle. 
Ptelea (Rutaceae). 
The leaf of P. trifoliata, L., contains saponin but I did not 
detect any in the seed. 
The leaves of the species examined are used in North America 
as an anthelmintic. 
Roupala (Proteaceae). 
The leaf of R. Pohlii, Meissn., contains saponin; a smaller 
amount also occurs in that of R. ‘ervaineana, Hort. (a variety of 
_R. elegans, Pohl?) : in addition leaves of both contain tannin. 
Ruscus (Liliaceae). 
The foliage, but not the seeds, of R. aculeatus, L., must be 
noted as containing saponin, 
The species examined has z.a. been regarded as an abortive ; in 
former times, and even now in some countries, it is much in 
request as a remedy, e.g.,as diuretic (and also a substitute for 
sarsaparilla). The same virtue is ascribed by Arabian physicians 
to the leaves of R. Hypoglossum, L., and R. Hypophylium, Li. 
_ Saururus (Saururaceae), 
Py ~The lea of S. lucidus, Donn (= S. cernuus, .), contains 
saponin, This natural order is closely related to Piperaceae where 
