BOTANY. 



chaffy appearance. The elegant wood- 

 sorrel has an elastic arillus, like a little 

 bag, serving to project the seeds to a dis- 

 tance. In the carex the same part is in 

 some degree inflated and membranous. 

 The covering of the seeds in the cyno- 

 glossum is considered by Dr. Smith as a 

 testa* rather than an arillus. Pappus, the 

 seed-down, in its most strict sense, is the 

 chaffv, feathery, or bristly crown of seve- 

 ral seeds that have no seed-vessel as in 

 the dandelion, thistle, scabious, and others. 

 In a more general sense, pappus is ap- 

 plied to any feathery or downy appen- 

 dage to seeds, even though lodged in a 

 pericarpium. Canda, a tail, is an elon- 

 gated appendage, originating from the 

 permanent style. It is generally feathery, 

 as in the virgin's bower, clematis. Ros- 

 trum, a beak, has a similar origin, but 

 usually belongs to a seed-vessel. Jtta, a 

 wing, is a dilated membranous appen- 

 dage, serving to waft seeds along in the 

 air. To all the above may be added va- 

 rious spines, hooks, scales, and crests, 

 generally serving to attach such seeds as 

 are furnished with them to the rough 

 coats of animals, and so to promote their 

 dispersion. This appears to be the final 

 purpose of the awns of grasses in gene- 

 ral. 



6. Receptaculum, fig. 48, the receptacle, 

 is the common base or point of connection 

 of the parts of fructification. It is essen- 

 tial, inasmuch as it must exist in some 

 form or other. This part, however, comes 

 chiefly into notice when it assumes any 

 peculiar form, as in compound flowers ; 

 the dandelion, daisy, and thistle, for in- 

 stance. In some of this class it is naked, 

 scaly, hairy, or cellular, and such circum- 

 stances afford excellent generic charac- 

 ters. Such of the natural order of Pro- 

 teaceae as have aggregate flowers are also 

 furnished with as conspicuous a recepta- 

 cle as the compound flowers. The re- 

 ceptacle of the seeds is a term used for 

 the part to which they are attached in a 

 seed-vessel. 



OF THE CLASSIFICATION OF KLAXTS. 



The species of plants, as well as of all 

 otl-er natural productions, are so im- 

 mensely numerous, that the most super- 

 ficial observer must be aware of the ne- 

 cessity of some regular mode of arrang- 

 ing them, as well as of naming and dis- 

 tinguishing them, in order to acquire or 

 to retain any clear knowledge of their na- 

 tures, differences, or comparative uses 

 Hence the distribution of plants into trees, 



shrubs, and herbs, into eatable, medici- 

 nal, or hurtful kinds, was very early con- 

 ceived ; for the human mind is naturally 

 prone to method and combination. When 

 the subject came to be scientifically stu- 

 died, various plans were formed, as dif- 

 ferent in ingenuity and utility as possible, 

 proceeding on various principles, but all 

 aiming at the same end, the commodious 

 arrangement of plants. The authors of 

 these various schemes seem all, as far as 

 they considered the matter with any such 

 view, to have thought their own plan 

 most consonant with that natural classifi- 

 cation, which every one at first sight per- 

 ceived to exist in the creation ; but a little 

 experience proved that the clue of nature 

 soon eluded their grasp. 



Linnxus, the first person who took a 

 very comprehensive and philosophical 

 view of the laws of system, and at the same 

 time carried them most happily into effect, 

 for the purpose of utility and facility, was 

 the first to perceive the difference be- 

 tween a natural arrangement and an arti- 

 ficial one. He ever considered the former 

 as the great desideratum of philosophical 

 botany, and indeed as necessary to be 

 kept in view by all who describe or de- 

 fine new discovered plants ; while the 

 latter was to be adopted for ready use and 

 convenience, just as words are arranged 

 in a dictionary according to their spell- 

 ing, without any regard to their deriva- 

 tions or analogical meanings. The same 

 great naturalist was also, from the first, 

 aware of the essential importance of the 

 principle laid down by Gesner and Cae- 

 salpinus, as we have already stated, that 

 plants ought to be arranged by their 

 parts of fructification alone, and not by 

 their general habit or structure indepen- 

 dent thereof. Hence he denominates 

 heterodox, all such systematics as class 

 vegetables by their leaves, roots, uses, 

 times of flowering, or places of growth, 

 for, strange to tell ! there have been 

 such ; and he esteems truly orthodox, 

 those botanists only who derive the cha- 

 racters of their systems from the flower 

 and fruit, in which, as he expresses it, the 

 true form or essence of their being is dis. 

 played. On this point all botanists are now 

 agreed, but they differ widely concerning 

 the eligibility of a natural or an artificial 

 system for daily use, as well as the princi- 

 ples upon which each ought to be founded. 



The earlier systematics began with the 

 consideration of the seed and seed-vessel, 

 forming their classes upon the situation 

 of the embryo, whether at the top or base 

 of the seed," and the number of the seeds 



