The ability to distinguish the character of odours seems to be a later development than taste differentiation. At least this is the case with regard to the enjoyment of agreeable smells. Among children of various ages experimented on by Perez, one of ten months showed some appreciation of the perfume of a rose,[34] but most children are probably first rendered susceptible to pleasure from scents by their association with flavours. Girls, however, seem to enjoy sweet smells as such more than boys do, though M. Guyan relates that he recalls vividly the _émotion penetrante_ which he experienced on inhaling for the first time the perfume of a lily.[35] With reference to adults, the same writer may be cited: “In spite of its relative incompleteness, the sense of smell has much to do with our enjoyment of landscape, whether actually viewed or vividly portrayed. No portrayal of Italy is complete without the softened atmosphere which recalls the perfume of its oranges, nor of Brittany or Gascony without the crisp sea air which Victor Hugo has so justly celebrated, nor of pine forests without suggestions of its aroma.” “The passion for smoking,” says Pilo (I give this to show how complicated our apparently simple enjoyments may be), “is so general because almost all the senses are flattered impartially by it; visceral, muscular, and taste sensations are involved in the use of the lungs which it calls for, the lips, tongue, teeth, and salivary glands through feelings of temperature; the senses of taste and smell through the piquant, aromatic flavour; hearing, in a very direct and intimate way, through the crackling of the leaves and the rhythmic inhaling and exhaling of the breath; and, finally, the sense of sight in gazing at the glowing cigar and soft, gray ashes and curling smoke which winds and glides upward in a fantastic spiral; while the brain, under the soothing influence of the narcotic, enjoys a repose enlivened by dreams and visions.”[36] Complete as this description appears, it yet misses one point—namely, the sucking movements which, from the recollections of the earliest months of life, we associate with pleasurable feeling. We may find the Des Esseintes of Huysmans’s romance useful once more. “Wishing now to enjoy a beautiful and varied landscape, he began to play full, sonorous chords, which at once called up before the vision a perspective of boundless prairie lands. By means of his vaporizer, the room was filled with an essence skilfully compounded by an artist hand and well deserving of its name—Extract of the Flowery Plain.... Having completed his background, which now stretched itself before his closed eyes in bold lines, he breathed over it all a light spray of essences, ... such as powdered and painted ladies use—stephanotis, ayapapa, opoponax, chypre, champaka, sarkanthus—and added a suspicion of lilac, to lend to this artificial life a touch of natural bloom and warmth of genuine sunshine.