38 Report of Schimmel § Co. 1922. 



•In the Alpes Maritimes in France, from 25 to 80000 kilos (on an average 40000 kilos) 

 per hectare and year can be obtained on well irrigated, artificially manured soil, if 

 great care is taken of the plants. In the Var department, the yield may come up to 

 75 and even 100000 kilos per hectare, according to L. Robertet. 



In Algeria the crops are estimated at from 25 to 27000 kilos per hectare. 



Blandini obtained from Pelargonium roseum, Willd., in Italy 26000 kilos of herb and 

 3945 kilos of flowers per hectare. 



. R. Knuth 1 ) has published an extensive article on geranium oil (botany, distribution, 

 cultivation and yield of the mother-plant and its varieties, chemistry of the oil and its 

 components), with several good pictures of Pelargonium species. The author thinks 

 that the plants cultivated in the various countries may be considered either as varieties 

 of cultivation or hybrids of other species, whose origin is now unknown or has been 

 forgotten long since. In the beginning of the nineteenth century, there was a sort of 

 fad to hybridize Pelargonium species, so that, for instance, the Geraniacece of Sweet 2 ) 

 (London 1820—1830) contain almost 500 of such artificial hybrids, whose origin already 

 at that time had been partly unknown. In the course of time, the origin of each cross 

 became more and more obscure, so that at the present time we are unable to determine 

 te exact origin of a large part of the pelargoniums found in our botanical gardens. 

 This is especially the case with regard to the species which were called lemon-geraniums 

 as early as the time of Sweet, and with which the rose-geranium must be included 3 ). 



Andrews 1 ), in his Geraniums (1805), mentions a Pelargonium oxoniense 5 ), closely 

 related to Pelargonium grareolens and Pelargonium capitatum, which was first cultivated 

 in Oxford on account of its rose-odour and sold under the name of Oxoniense roseum. 

 Knuth thinks it very probable that the parent plant of the rose-geranium was originally 

 purchased under the name of Oxoniense roseum and is related to Pelargonium oxoniense. 

 Heuze 6 ) and Cordemoy 7 ) are mistaken in thinking that the species chiefly cultivated in 

 Algeria and Reunion is Pelargonium capitatum, as the plant found there has leaves 

 entirely different in shape from those of P. capitatum. This species rather belongs to 

 the group of Pelargonium graveolens, L'Herit. 



It is probable that in France, in addition to rose-geranium, Pelargonium ocloratissimum 

 (L), Ait. (belonging to the section of Peristera, according to Harvey) and Pelargonium 

 fr.agrans. Willd. (a hybrid of Pelargonium ocloratissimum and P. exstipulatum, L'Herit.) 

 are cultivated, though to a smaller extent. Both plants have a delicate texture and 

 differ also in other ways from the rose-pelargonium. In Algeria and Reunion the two 

 species are certainly not cultivated. 



The oil is furnished by the glands of the plant. These are found, as in all pelar- 

 gonium species, in the green parts, especially on the surface bf the leaves, where they 

 are shorter than on the stem and the peduncles. In most cases they are from V 18 to 

 1 /i-> mm. long and can be seen with the naked eye. They consist of from one to three 

 small cylindrical base cells and a small globular head, in which latter the oil is 

 generally to be found When young, the end cell is colourless, later on it is coloured 

 by a yellow substance and finally becomes brown. The oil glands are of great use to 

 the plant, as they protect it against insects and snails. As a matter of fact, all pelar- 

 goniums are but little damaged by such enemies. 



x ) Americ. Journ. Pharm. 93 (1921), 302. — 2 ) Died as a market-gardener in London. — 3 ) Knuth 

 calls "rose-geranium" the chief parent plant of geranium oil. See lower down. — 4 ) Herbalist in London, 

 who published precious copper plates of foreign plants. — B ) Pelargonium oxoniense, van Eeden (Index 

 Kewensis). — «) Revue Horticole 65 (1893), 305. — 7 ) Revue Cult. Colon. 1904, 170. 



