MONOCHLAMYDEiE. 653 



formerly much used as a crimson dye. Oak trees are especially liable to 

 be attacked by insects, which thus produce excrescences, commonly called 

 ffalls. The more important of these excrescences are the Nut Galls of com- 

 merce, and the large Mecca or Bussorah GaUs of Pereira. The latter are 

 also called Bead-sea apples, ii»ad apples, and apples of Sodom : they are pro- 

 duced by Cynips insaita on the Quercus infectoria. The former are pro- 

 duced on the branches of Quercus infectoria by the Diplolepis Gallce tinc- 

 torial. They are extensively employed in tanning, for making ink. andfor other 

 purposes in the arts. They likewise possess tonic, astringent, and anti- 

 periodic properties. Pereira also regarded them as a valuable antidote in 

 poisoning by Tartar Emetic. The best Nut Galls come from the Levant. 

 Two kinds are especially distinguished under the names of blue and white 

 galls. The dai'k coloured imperforate galls are the most valuable. The 

 round smooth galls, noAV commonly found on the lower branches of the 

 Oaks in this country, although containing tannic acid, are far less valuable 

 than commercial nut-galls. The acorns of some species of Quercus, as Q. 

 Ballota, Q. Gramuntia, Q. ^sculus, and Q. Hiiidsii, are edible. 



Natural Order 230. Myricace^. — The Gale or Bog-Myrtle 

 Order. — Character. — Shrubby plants, with alternate simple 

 resinous-dotted leaves. Flowers unisexual, amentaceous. Male 

 flowers aehlamydeous ; stamens definite. Female flowers with a 

 1 -celled ovary, and 1 erect ovule ; fruit drupaceous ; seed solitary, 

 erect ; embryo without albumen ; radicle superior. 



Distribution, cfc. — Natives of the temperate parts of Europe 

 and North America, and of the tropical regions of South America, 

 India, and the Cape of Good Hope. Examples of the Genera : — 

 Myrica, Comptonia. There are about 20 species. 



Properties and Uses. — The plants of this order are chiefly 

 remarkable for aromatic and astringent properties. 



Comptonia aspJenifolia, Sweet Fern, is employed in the United States as 

 an astringent and tonic in diarrhcea. 



Myrica. — M, cerifera, the Waxben-y, Candleberry, or Wax Myrtle. The 

 bark of the root is extensively used in the United States as a stimulant as- 

 tringent in diarrhoea and dysentery. The fruits when boiled yield the kind 

 of wax known as Myrtle Wax. Other species of Myrica yield a somewhat 

 similar waxy substance. The fruit of M. sapida is eaten in Nepaul. Its 

 bark is an aromatic stimulftnt, and is employed in some parts of India as a 

 rubefacient and sternutatory. 



Natural Order 231. CASUARiNACEiE. — The Beef wood Order. — 

 Character. — Trees, with pendulous jointed striated branches, 

 without evident leaves. Flowers in bracteated spikes or heads, 

 unisexual. Male flowers with 2 sepals united at their points, 

 and 2 alternating bracts ; 1 stamen, and a 2-celled anther. 

 Female flowers in dense spikes or heads, naked, but each having 

 2 bracts; ovary 1-celled, with 1 — 2 ascending ovules, and 2 

 styles. Fruits winged, indehiscent, collected together into a 

 cone-shaped body under the thickened bracts. Seeds without 

 albumen ; radicle superior. 



Distribution, ^'c. — They are principally natives of Australia. 

 They are called Beef-wood trees from the colour of their timber 

 resembling raw beef. In general appearance they much resemble 

 tlie branched Equiseta. There is 1 genus, and about 32 species. 



