311 



Geography. The earliest Flora of the globe, that indicated by the fossil 

 remains in the coal measures, was composed of Ferns, almost to the exclusion 

 of other plants ; and even in these islands, where the tribe now forms an incon- 

 spicuous feature in the vegetation, grasses, herbs, and trees, were represented 

 by herbaceous and arborescent Ferns, and Fern-like plants. An approach to 

 this enormous disproportion between Ferns and the rest of the Flora is even 

 now exhibited in certain tropical islands, such as Jamaica, where they are l-9th 

 of the Phaenogamous plants ; New Guinea, where D'Lrville found them as 28 

 to 122 ; New Ireland, where they were as 13 to 60 ; and in the Sandwich 

 Islands, where they were as 40 to 160 ; and it is clear, from the collections of 

 Dr. Wallich, that Ferns must form a most important feature in the Indian Ar- 

 chipelago. Upon continents, however, they are far less numerous : thus, in 

 equinoctial America Humboldt does not estimate thp.m higher than l-36lh ; 

 and in New Holland Mr. Brown finds them l-37th. They decrease in pro- 

 portion towards either pole : so that in France they are only l-63d ; in Portu- 

 gal, 1-1 16th; in the Greek Archipelago, 1 -227th ; and in Egypt, l-971st. 

 Northwards of these countries their proportion again augments, so that they 

 form l-31st of the Phsenogamous vegetation of Scotland ; l-35th in Sweden ; 

 l-18th in Iceland ; l-10th in Greenland ; and l-7th at North Cape. (See a 

 very good paper upon this subject by D'Urville, in the Ann. des Sc. Nat. 6. 

 51. ; also Brown's Appendix to the Congo Voyage, 461.) Mr. Brown has ob- 

 served (Flinders, 584), that it is remarkable, that although arborescent Ferns 

 are found at the southern extremity of Van Diemen's Island, and even at 

 Dusky Bay in New Zealand, in nearly 46° south latitude, yet they have in no 

 case been found beyond the northern tropic. 



Properties. The leaves generally contain a thick astringent mucilage, 

 with a little aroma, on which account many are considered pectoral and leni- 

 tive, especially Adiantum. pedatum and Capillus Veneris ; but almost any 

 others may be substituted for them. Capillaire is so called from being prepared 

 from the Adiantum Capillus Veneris, a plant which is considered to be un- 

 doubtedly pectoral and slightly astringent ; though its decoction, if strong, is, 

 according to Dr. Ainslie, a certain emetic. The Peruvian Poly podium Cala- 

 guala, Acrostichum Huacsaro, and Polypodium crassifolium, are said to be 

 possessed of important medicinal properties, especially the former ; their effects 

 are reported to be solvent, deobstruent, sudorific, and antirheumatic ; antivene- 

 real and febrifugal virtues are also ascribed to them. See the Pharmacopozia 

 Madritensis, 1792, and Lambert's Illustration of the Genus Cinchona, 114. 

 The leaves of Adiantum melanocaulon are believed to be tonic in India. Ains- 

 lie, 2. 215. The tubes of the pipes of the Brazilian negroes are manufactured 

 from the stalk of Mertensia dichotoma, which they call Samanbaya. Pr. Max. 

 Trav. 96. The bruised fronds of the fragrant Angiopteris evecta are employed 

 in the Sandwich Islands to perfume the Cocoa-nut oil. Polypodium phyma- 

 todes is also used for the same purposes. D'Urv. The stem is, on the con- 

 trary, both bitter and astringent ; whence that of many species, such as Aspi- 

 diurn Filix Mas, and Pteris aquilina, has been employed as an anthelmintic. 

 They have also been given as emmenagogues and purgatives. Osmunda 

 regalis has been employed successfully, in doses of 3 drachms, in the rickets. 

 The rhizoma of Aspidium Filix Mas has been analyzed, and found by M. Morin 

 to contain, 1st, volatile oil ; 2d, a fat matter composed of elaine and stearine ; 

 3d, gallic and acetic acids ; 4th, uncrystallisable sugar ; 5th, tannin ; 6th, 

 soap ; 7th, a gelatinous matter insoluble in water and in alcohol. It contains 

 also the subcarbonate, sulphate, and hydrochlorate of potash, carbonate and 

 phosphate of lime, alumine, silex, and oxyde of iron. Brewster, 2. 176. The 

 roots of Nephrodium esculentum are eaten in Nipal, according to Dr. Buchan- 

 an. Don Prodr. 6. Those of Angiopteris evecta are used for food in the 



