118 Report of Schimmel § Co. 1922. 



When repeating the experiment with water on which oleic acid had been spread 

 out previously, a halo was likewise formed, the diameter of which allowed of comparing 

 the relative surface tension. Hereby the following figures resulted: — dimethylpyrolidone, 

 31.5; dimethyl campholic acid amide, 29.7; isobutylborneol (-camphol), 20,4; menthol, 

 20.4; ^-toluidine, 16.7; camphor, 13; thymol, 12.1; borneol, 11.1; propylcamphocarbonic 

 acid methyl ester, 9.4; benzal camphor, 0.94. 



According to F. Hogewind 1 ), nearly all odoriferous bodies, after long standing of 

 their aqueous solution, show colloid properties. The odour was then found to be but 

 slightly less intense than with the original oil; in addition, a layer of pure water, 

 when poured carefully on such a colloidal solution, was found to assume the odour 

 of the aromatic in question. These phenomena are readily explained by the well-known 

 fact that the bodies mentioned show more or less the tendency to polymerise and 

 resinify partly. In this process products are always formed which are far less soluble, 

 and which, owing to the low concentration of the initial solutions, yield stable hydrosols. 



A. Miiller 2 ) describes and recemmends an apparatus for determining the viscosity 

 of essential oils termed "viscosostalagmometer". As years ago 3 ) we established by 

 way of experiment that the determination of this constant is of but little value when 

 judging essential oils, we need not enter into a description of Muller's apparatus, 

 which in its main features differs but slightly from the ^viscosimeters devised by 

 Arrhenius, Ubbelohde, Engler, and others. 



Botanical Notes. 



Two hybrids of spike and lavender are described by M. Humbert 4 ). 



Hybrid A, growing up to 1 m. height, resembles in general habit and appearance 

 a strong L. latifolia and is found here and there, more or less isolated, in the north 

 of St. Saturnin-les-Apt at about 800 m. altitude, also near Buis-les-Baronnies about 

 400 m. altitude, in the Nyonais, and in the Causses. The flower stalks, divergent as in 

 L. latifolia, generally bear in the axils of two higher leaves a pair of secondary flowering 

 branches. At the base of the bushy, more or less interrupted inflorescences, often 

 exceeding 10 cm. in length, the pairs of lower leaves form false rosettes. The bracts, 

 in whose axils 6 to 12 flowers stand, remain green a long time even after flowering, 

 at least in their upper part. 



Hybrid B, whose height varies between 30 and 80 cm., resembles more L. officinalis, 

 is found in great abundance throughout the entire zone of contact between L. latifolia 

 and L. officinalis, often as numerous as the parents. The flower stalks are more or 

 less divergent, generally simple, but sometimes bear in the axils of two higher leaves 

 a pair of secondary branches. The lower leaves, approaching the base of the flower- 

 bearing branches, form false rosettes but not so distinct as in L. latifolia or in 

 hybrid A. The bracts are brown and membraneous after flowering. The slender 

 inflorescence is 1.5 to 6 cm. long, usually not interrupted; 1 <to 5 flowers stand in 

 the axil of each bract. 



The following characters are common to both hybrids:— 1. The flowering begins 

 later than in L. officinalis and earlier than in L. latifolia. 2. The seeds are almost always 

 sterile. 3. On bruising the plant a camphoraceous odour is noticed. 



x ) Archives ne'erland. dePhysiol.de Vhomme et des animaux 5 (1920), 153. — 2 ) Chem.-Ztg. 45 (1921), 759. 

 — 8 ) Cf. Report April 1901, 31. — *) Perfum. Record 12 (1921), 177. 



