•:?111'ontribute a considerable de ee of •d•ii::•:tonal support, and this can be supple- '•(g,f•.mented by galbanum, myrrh, scam- •:•?i?mony, patchouli and vetivert, but !•i:iii!!i as the choice of commercially avail- •}•}•:able oak moss extracts, resins and •?}?absohtes a•ords such considerable •/•,•?•:latitude, the perfumer who has in ?:?mind elegant creations of cr•p•, :•}{?•:•:Chypre, foug•re and similar fant•y is not particularly inter- in syffthehc imitations of this ::.•i½:(:::.:vi•ually indispensable item. THE ODOURS OF FERNS 9.•" • ::•}::?• As is readily perceived, the fern : •?:::.•ødour links the verdure-lichen note ::j •th the earthy tones, and although •?::the odour of the rhizome of the :•:•.?'MMe fern (Dryopteris filix-mas) is not very pleasant, somewhat resem- • •bling thi oily dankness of octyl •:}' butyrate, yet the foliage odours of many other species of ferns is particu- larly attractive to the perfumer. Many examples of this are to be found in the Adiantum•the scented maiden-hair ferns, and particularly with the D. aemula•the hay-scented Buckler fern, and this coumarinic note is also well evidenced in the •oup comprising the Hound's or Deer-tongue family (Liatris odoraris- sired), as is seen by some of the common names of these plants' wild vanilla and sweet vernal. From the pe•umery angle, how- ever, the scented-fern or foug•re odour is fundamentally that of oak- moss Mlied with patcho•i, as t•s combination seems to a•ow a •adual unfoldment of a peculiarly attractive PERFUMES - sweet, velvety cassia-clove under- tone, which when slightly augmented by a woodruff-vanilla shading and extended by lavender, constitutes a foundation upon which many inter- esting variations can be made. For instance, the replacement of the coumarin by some of the methyl- or i hydro-coumarins, or simulations of Melilot, based upon di-methyl hydro- quinone, Melilotal (p-methyl aceto- phenone) and ani.syl esters, ethers and ketones, provides some very pleasing and intriguing notes. Furthermore, upon more deliber- ate consideration, it is noted that there are four adjuvants which are integral to the make-up of "fern- frond" perfumeg, namely, a slightly herbaceous thyme note which may be obtained by the judicious addition of carvacryl acetate or benzoate' also the incidence of the odour of freshly bruised fern stems, which will be found in cuminic acetaldehyde there.is also a touch of the pungency associated with ethylamyl, methyl- hexyl and similar "lavender" ketones' and, f•nally, bearing in mind the relationship of the primeval giant ferns with the coniferae--in iso-bornyl propionate will be found the requisite pine inflection to com- plete the foug•re gamut. THE ]EARTHY ODouR This-is a somewhat recondite section and may perhaps be intro- duced by calling attention to a very apt excerpt from W. H. Hudson's "Hampshire Days." Writing in 1902, he says, "It here comes into 191

JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS my mind that the very smell of the earth, in which we all delight, the smell which fills the air after rain in summer, and is strong when we turn up a spadeful of fresh mould, which the rustic calls "good," believing, perhaps rightly, that we must smell it every day to be well and live long, is yet after all, an odour given off by a living thing--Cladothrix 'odori- fera--too small for human eyes . . . yet they are able to find a passage to us through the other subtler sense and from the beginning of our earthly journey even to its end, we walk with this odour in our nostrils, and love it .... " It would seem, however, that Dr. Hugh Nicol has assembled most of the references to the scanty litera- ture on this subject, in an article published in 1933 and a later contri- bution entitled "The production of odorous substances by the aid of micro-organisms.' ,4 These papers con- tain many items of interest to the thoughtful perfumer. The second contribution mentions that the basic earthy odour has been ascribed to .the Actinomycetes (or ray-fungus), but I think the point of outstanding interest is that dealing with the .fungal decomposition of glucose, resulting in the production, not only of ethyl acetate, but of other sweet, ethereal "woody and autumnal" esters. In practical perfumery, the earthy odour may perhaps be best described as a blend of the oakmoss fundamen- tal, with a moderate ferny undertone which includes a trace of a sweet fungal element. Light touches of 192 such bases add a desirable similitude of naturalness to folial compositions, and these in their turn can be used to impart a distinctive tonality to cyclamen, gardenia, mignonette, muguet and tuberose compositions. In so far as synthetics are con- cerned, an unmistakably earthy odour is associated with iso-butyl quinoline and linalyl-heptyl ether, and this is even more evident when they are blended with fenchyl alcohol but the approach to the odour of freshly turned earth can be simulated with greater fidelity by incorporating such elementary bases with anethole-containing oils such !, as dill or fennel, shading with basil, :: pennyroyal, rue and sage, and add- ing, as a final touch, a little of a ß: rhodinol fraction exhibiting the char- acteristic wet-straw note. THE F-UNGAL AROMA This term needs a little clarifying,.'::: because the natural odour varies.: . from the pleasantly culinary (and sometimes perfumed) aroma of the edible mushrooms to the unpleasanti:: I dankness of the poisonous toadstools ' we have also the s.ickly sweetnessi' exhibited by .many types of mildew: " and the sour or vinous "secondaryl .. fermentation" odour associated with: various moulds. Furthermore, there is a wide:i .: diversity in these aromas in the fresh ::i• and damp stage as compared with?if_! those of the humus or air-dried?i? spores, but from the perfumery view-..[?i point it is probable that the pleasanti',7i Champignon prototype is found tø?-i :!