946 ARBORETUM ET FRUTICETUM BRITANNICUM. 



climate of London, attaining the height 

 of 10 or 12 feet in 10 years ; and, in 

 40 or 50 years, the height of as many 

 feet. The wood of the ginkgo is said by 

 Kaempfer to be light, soft, and weak ; but 

 Loiseleur Deslongchamps describes it as of 

 a yellowish white, veined, with a fine close 

 grain, and moderately hard. It is easy to 

 work, receives a fine polish, and resem- 

 bles in its general appearance citron wood. 

 The salisburia, judging from the speci- 

 mens in the neighbourhood of London, 

 thrives best on a deep sandy loam, perfectly 



dry at bottom ; but it by no means prospers in a situation where the subsoil is 

 wet. The situation should be sheltered, but not so much so as for many 

 exotic trees which have longer leaves and more widely spreading branches. 

 Propagated by layers of two-years-old wood, which generally require two 

 years to be properly rooted ; but, on the Continent, it has been found that, 

 by watering the layers freely during the summer, they may be taken off in the 

 autumn of the year in which they were made. Cuttings made in March, of 

 one-year-old wood, slipped off with a heel, root in a mixture of loam and 

 peat earth in the shade ; and their growth will be the more certain if they have 

 a little bottom heat. Cuttings of the young wood, taken off before midsummer, 

 and prepared and planted with the leaves on, in sand, under a bell-glass, will, 

 we have no doubt, succeed perfectly. 



ORDER LXXVII. CONFFER^, OR PINA^CEJE. 



Identification. Lindl. Nat Syst. of Bot., p. 31a. .-, Richard Mem. Conif., in part. 



Synonymes, Coniferae Rich. Mem. Conif. The Coniferae, till lately, included the order Taxaceae, 



already given, p. 938., which has been separated from it by Dr. Lindley. Conacese Lindl. Key, 232. 

 Affinities. The Taxacea* have been separated from this order on the one hand, while, on the other, 



the Cycadaceae are considered as approaching very near it. 



ORD. CHAR. Flowers unisexual ; those of the two sexes in distinct catkins 

 which are situated upon one plant in most of the species, and upon two plants 

 in the rest. Male catkin longer than broad. Each flower a scale or 

 body, bearing pollen contained within either 2 cells formed within the scale 

 or body, or 3 or more 1 -celled cases; in Araucaria Juss., in 2-celled cases, 

 exterior to, but united with, the scale or body : a part of the scale or body 

 is free above the cells or cases containing the pollen. Female catkin more 

 or less conical, cylindrical, or round, in figure ; composed of many, several, or 

 few flowers, each, in most species, subtended by a bractea. The catkin, in 

 the state of fruit, is rendered a strobile of much the same figure. Each 

 flower is constituted of 1 3 ovules, borne from an ovary that resembles a 

 scale, and is in some instances connate with the bractea that subtends it. 

 Ovules regarded as receiving impregnation from direct contact of the pollen 

 with the foramen of the ovule. Bracteas imbricated. Carpels, which are 

 the ovaries in an enlarged and ripened state, imbricated. Seed having in 

 many species a membranous wing. Embryo included within a fleshy oily 

 albumen, and having from 2 to many opposite cotyledons, and the radicle 

 being next the tip of the seed, and having an organic connexion with the 

 albumen. Brown has noticed a very general tendency in some species of 

 Pinus and J^bies to produce several embryos in a seed. 



Leaves simple, alternate, exstipulate, evergreen, rarely deciduous ; needle- 

 shaped, scale-like, or lanceolate ; in some species disposed in groups, with 

 a membranous sheath about the base of the group, at least in most of 

 these ; in some in rows ; in some oppositely in pairs, decussate in direction ; 

 imbricately in several. Floivers in catkins ; April and May. Fruit a cone ; 



