ALE 



[12] 



A L G 



bable, that the new layers of albur- 

 num and liber, which are produced 

 each year on the outside of all 

 that preceded, are formed by the 

 descending fibres, or roots, of the 

 leaf-buds. 



ALCYO'JSTIUM:. A genus of zoophytes, 

 the characters of which are, that 

 the animal grows in the form of a 

 plant ; the stem, or root, is fixed, 

 fleshy, gelatinous, spongy, or coria- 

 ceous, with a cellular epidermis, 

 penetrated with stellated pores, and 

 shooting out tentaculated oviparous 

 hydree. Encyclop. 



From the experiments of Hat- 

 chett, it appears that these animals 

 are composed principally of carbo- 

 nate of lime and a little gelatinous 

 matter. The alcyonium belongs to 

 the class Vermes, order Zoophyta. 

 Guvier places the alcyonium in 

 the order Coralliferi, class Polypi. 

 Much obscurity prevails in the 

 distribution even of the recent 

 species of the families of alcyonium 

 and spongia. Ellis makes their 

 distinction to consist in the presence 

 of polypi, as inhabitants of the 

 cells of alcyonia, and believes the 

 sponges to possess none of these 

 animalcules, but to be simply in- 

 vested with a living gelatinous 

 flesh. Lamark, however, supposes 

 the sponges to have polypi, like 

 the alcyonia, differing only in the 

 greater solidity of the fleshy parts 

 of the latter, which permit them 

 to be observed when removed from 

 the water; while those of the 

 former dry up instantly on being 

 taken out of their natural element. 



ALCY'ONITE. Alcyonites are fossil 

 alcyonia, or zoophytes nearly allied 

 to sponges, the production or habi- 

 tation of polypi. BaJzewell. 



ALE'MBIC. (alamUc, Fr. lambicco, It. 

 alenibicum, Lat.) A vessel used in 

 the process of distillation, usually 

 made of glass or copper. Of alem- 

 bics there are two different forms, 

 the beaked and the blind, the former 



having communication with the re- 

 ceiving vessel, the latter being 

 without such. The use of the 

 alembic has yielded to that of the 

 retort. 



ALE'PIDOTE. (from , priv. and XeTrJ?, 

 squama, a scale.) Any fish destitute 

 of scales, as the eel, cod-fish, &c. 



A'LGA. (Lat.) Sea-weed. 



A'LG^E. An order, or division, of the 

 Cryptogamas class of plants. It is 

 one of the seven families, or natural 

 tribes, into which Linna3us distri- 

 buted the vegetable kingdom. The 

 whole of the sea-weeds are compre- 

 hended under this division. The 

 plants belonging to this order are 

 described as having their leaf, stem, 

 and root all one. The depths at 

 which, according to Syell, some 

 of the alga3 live, is extremely 

 great, being no less than one thou- 

 sand feet ; " and although in such 

 situations there must reign dark- 

 ness more profound than night, at 

 least to our organs, many of these 

 vegetables are highly coloured." 

 Principles of Geology. 



M. Lainouroux states that the 

 groups of alga3, or marine plants, 

 affect particular temperatures or 

 zones of latitude, though some few 

 genera prevail throughout the 

 ocean. Some of the algse grow to 

 the enormous length of several 

 hundred feet, and are all highly 

 coloured, though many of them 

 must grow in the deep caverns of 

 the ocean, in total, or almost total, 

 darkness. From the observations 

 of Humboldt, who discovered green 

 plants growing in complete dark- 

 ness at the bottom of one of the 

 mines of Freyberg, it may be con- 

 cluded that light is not the only 

 principle on which the colour of 

 vegetables depends. 



ALGALMA'TOLITE. Figure-stone. A 

 mineral, the finest varieties of 

 which we receive from China. A 

 sub-species of talc-mica. See Agal- 

 matolite. 



