

THE FARMER AT HOME. 147 



the exterior. In the first case the plant is called endogenous, and in 

 the last, exogenous. All trees belonging to the family of palms, the 

 date, cocoa-nut tree, bread-fruit tree, the bamboo, sugar cane, and 

 indeed most of the trees belonging to tropical climates, as well as all 

 gramineous and lilaceous plants, are endogenous. On the contrary, 

 most of the trees of temperate or northern regions, such as the oak, 

 pines, and elms, and the various fruit trees, are exogenous. In the 

 first, each successive addition is made from within, like, drawing out 

 an additional slide to a telescope ; in the last the addition is made 

 between the bark and the Avood of the previous year's growth, and 

 these successive layers determine the age of the tree, as the joints of 

 the palm do that class. The stems of endogenous plants, after they 

 become consolidated, never increase in size ; they can only increase 

 in height ; while the exogenous ones continue to increase in circum- 

 ference as well as in height during their whole life. 



ENRICHING-PLANTS. A term used by lull and other 

 farmers to designate such plants as are found to improve land, rather 

 than to exhaust it, and in consequence of which the same piece of 

 land will produce a good crop of corn, though it would, without the 

 assistance of their having been planted on it, have yielded a very 

 poor one. The mystery of this difference between plants, some of 

 which are found to burn up, that is, impoverish lands, while others 

 enrich it, and leave it fitter for succeeding crops than they found it, is 

 explained by Mr. Tull. This author having observed, that breaking 

 the earth, by digging or horse-hoeing between the plants, gave them 

 great increase, found that it was this practice that enriched the earth ; 

 and that, while corn and such plants as stand close, and cannot be 

 hoed between, impoverish the ground, and suffer no means of enriching 

 it again to be used, there were some other things, the crops of which 

 being planted thinner, gave room to the earth to be ploughed, dug, or 

 hoed between, and that these were the plants which were called the 

 enriching kinds by farmers ; and the whole secret lay in this, that the 

 hoeing, ploughing, or otherwise breaking the earth between them, in 

 order to kill the weeds, enriched the ground greatly more, in propor- 

 tion, than these plants exhausted it ; arid the consequence was, that 

 though they had thriven very well, yet the earth was left richer than 

 before, notwithstanding all that they had imbibed from it. 



EPIDERMIS. In botany the exterior cellular coating of the 

 *rk, leaf, or stem of plants or trees. It is composed of cells com- 

 peted together into a stratum, varying in thickness in different spe- 

 cies, and is often readily separable by gentle violence. It is believed 

 to be intended by nature as a protection of the subjacent parts from 

 the drying effects of the atmosphere. 



ERA. An account of time, reckoned from any particular period, 

 term, or epoch. The Jews had several eras, as from the creation of 



