(From Folium 3814 a leaf). A leaf; called folium, to distinguish it from the leaf of a flower, which is called petalum. See Petala.

A leaf is termed: 1. Folium abruptum pinnatum, abruptly pinnate, when they have neither leaflet, nor tendril, nor clasper at the end. 2. Acinaciforme, sabre-shaped. 3. Acuminatum, awl-winged, or Integerrimum, entire. 4. Acutum, acute. 5. Bifidum, bifid. 6. Bt-natum, two lobed. 7. Canaliculatum, channelled. 8. Cartilagineum, cartilaginous. 9. Ciliatum, ciliated. 10. Cirrhous, winged leaf. 11. Conjugatum, conjugated. 12. Cordato hastatum, heart arrow pointed. 13. Cor-datum, heart shaped. 14. Crenatun, cvenated. 15. Cre-natum acutum, acute crenated. 16. .Crenatum duplex, double crenated. 17. Crenatum obtusum, obtuse crenated. 18. Crisfium, curled. 19. Cuneiforme, wedge shaped. 20. Decompositum, decomposite. 21. Decur-rens, running winged. 22. Deltoidea, deltoid, resembling the Greek A. 23. Digitatum, resembling a hand with the fingers extended. 24. Dolabriforme, hatchet shaped. 25. Duplicatio pinnatum, vel Pinnato pinna-turn, doubly winged. 26. Duplicato serratum, doubly serrated. 27. Erosum, eroded. 28. Hastdtum, pike, or javelin shaped. 29. Hispidum, thorny, stinging. 30. Integerrimum, perfectly entire. 31. Lacerum, lacerated, or torn. 32. Lanciniatum, jagged. 33. Lanceolatum, spear shaped. 34. Lineare, linear, narrow. 35. Lin-guiforme, tongue shaped. 36. Lunatum, moon shaped. 37. Lyra turn, lyre shaped. 38. Nervosum, nervous, fibrous. 39. Oblong. 40. Obtuse. 41. Obtusum cum acumine, blunt pointed. 42. Orbiculum, round. 43. Ovatum, oval. 44. Oval, or Elliptic. 45. Palmatum, palmated. 46. Papillosum, warted. 47. Pilosum, piled, or like velvet. 48. Pinnatifidum, wing pointed. 49/ Pinnato pinnatum,double winged. 50. Pinnatum abrup-tum, abrupt winged. 51. Pinnatum cum impari, winged, with one pinna in excess. 52. Plicatum, plaited. 53. Praemorsum, bitten. 54. Quinque angulare, five-cornered. 55. Quinque partita, divided into five parts. 56. Racemosum, branching. 57. Reniforme, kidney shaped. 58. Repandidum, notched. 59. Pugosum, wrinkled. 60. Sagittatum, arrow pointed. 61. Serratum, sawed. 62. Sinuato dentatum, indented, sinuated. 63. Sinua-tum, sinuated. 64. Subrotundum, roundish. 65. Su-bulatum,awl shaped. 66. Supra decomposite. 67. Teres, taper. 68. Ternatum, trifoliate. 69. Tomentosum, downy. 70. Triangulare, triangular. 71. Trilobum, trilobated. 72. Triplicato ternatum, triply trifoliate. 73. Wing leaf, with membranous foot stalks.

Leaves consist of a parenchymatous matter dispersed in the meshes of a net work, and the whole is covered by an expansion of the epidermis of the pedicle or footstalk. The upper pagina of the leaf seems designed to throw off the excrementitious exhalations of the plant, and the under to imbibe moisture. It is necessary for these purposes that the light should have access to that part which is designed for the separation of the oxygen; and if a leaf is forcibly turned, by an opposite curvature of its foot stalk, it restores the upper pagina to the sun's rays. Leaves have been consequently supposed to beat-some analogy to the lungs of animals.

Folium. It is the name of the philosopher's stone: and of that triangular membranaceous sinus, where the sagittal and coronal sutures in infants meet: it signifies a relaxed uvula in Arnaldus. See also Dexamene.

FoliUm, called also fol. Indum, malabathrum, mala-batrum, tamalapatrum; cardegi Indi; catou-karua, pseudocassia; India leaf; is of a firm texture, of an oblong oval shape, pointed at both ends, smooth and glossy on the upper side, and less so on the under; of a yellowish green above, and of a pale brownish colour beneath, furnished with three ribs running its whole length, one very protuberant on the lower side, and two smaller ones which bound the edges. Both the leaves and their pedicles are very mucilaginous; chewed, they render the saliva slimy or glutinous; infused in water, they yield a large quantity of strong tenacious mucilage; but they possess little of the strong aroma of the bark. These leaves, according to Ray, are diuretic. It is an ingredient in the theriaca, and supposed by Bosc, from an examination of different specimens, to be the leaves of the laurus cassia Lin. Sp. Pl. 528. See Lewis's Materia Medica.