CLASSIFICATION OF PLANTS. 



105 



plants often assume the form of a flat expansion (thallus), 

 whence they derive their name of ThaHophytes, or plants 

 growing in flat masses. Lichens, Fungi, and Sea-weeds, 

 constitute this last, and lowest class of vegetation. 



NOMENCLATURE. 



You have seen that every plant is a species of some Genus, and that this 

 genus is again included under some Order. These orders, genera and species, 

 iinvr Latin names. The names of the Orders are Latin adjectives, mostly de- 

 rived from some prominent genus in the order, and usually ending in acea; 

 the noun plunhr being understood, sis Rosaceae, derived from Rosa, and mean- 

 ing plants of the Rose tribe. Sometimes they have names which were given 

 before the Natural System was adopted, and have been retained on account of 

 their significance, such as Leguininoste, plants with a pod, and Conifene, Cone- 

 bearing trees. 



The names of the Genera arc Latin nouns. These are sometimes the an- 

 cient names, as Viola, the Violet, Urtica, the Nettle. They are often formed 

 arbitrarily from Latin, or more frequently from Greek words, to denote some 

 quality of the plant, or some peculiarity of its structure, as Liriodendron (Lily- 

 tree), derived from two Greek words, signifying respectively, Lily and Tree. 

 They are also formed from the names of some, distinguished Botanist, or patron 

 of Botany, as Linnsaa, from Linnieus, Magnolia, from Magnol. 



The Species are designated by Latin adjectives, or substantives used as ad- 

 jectives, which are placed alter the generic name; and the two together form 

 what is called the Botanical name. These adjectives generally denote some 

 quality, or peculiarity of the plant, or sometimes its native district, as Rosa alba, 

 the White Rose, Quercus tinctoria, the Oak used in dying, Cornus Canadensis, 

 a Cornus native in Canada. The specific name is also often derived from the 

 same of a person. If the person was the discoverer of the species, the specific 

 name i- in the genitive singular, as Desmodium Dillenii, a Desmodium dis- 

 covered by Dillenius ; otherwise it is an adjective ending in ntts, na, or num, 

 according to the gender, as the Carex Deweyana, a Cares named in honor of 

 Prof. Dewey. 



The names of Classes, Orders, and Genera, always begin with capitals, being 

 proper names, and also all specific names derived from persons, or places, or 

 from nouns used as adjectives, as Daucus Carota, where the specific name is a 

 noun. 



In order that those unacquainted with Latin may find no difficulty in pro- 

 nunciation, all words of three or more syllables are marked with an accent, 

 thus, Lupinus, to denote the accented syllable. Words of but two syllables al- 

 ways have the accent on the fkst 



In all names derived from ftie Latin or Greek, that is, all but personal names, 

 or names derived from some locality, the pronunciation of which is of course 

 determined by the original word, every letter must always be pronounced, 

 thus, in Andmone, the final e, so often silent in English, must be sounded. The 

 final a must have the sound of ah, but less prolonged. Thus we pronounce 

 Malva MalvaA, and not Malcay. Ch should always have the sound of *; and 

 all the other letters have the same sound as in English. 



BOTANICAL ANALYSIS. 



The examination of a plant, in order to determine its class, order, and botan- 

 ical name, is called ANALYSIS. A thorough knowledge of all these particulars is 

 indispensable to a full understanding of the true nature and affinities of the va- 

 rious plants which come under our observation. The continual habit of analyz- 

 ing plants gives us an acquaintance with their structure, their qualities and 

 habits, more complete and thorough, than can be obtained by the most faithful 

 study of books. I would, therefore, enjoin it upon the sincere student of the 

 science, to seize every opportunity of studying the plants themselves, and thus 

 add to his theoretical ideas the still more valuable practical knowledge. 



In order that this object may be attained by the beginner, with the greatest 

 possible ease and certainty, the descriptions of the Orders have an artificial 

 analysis prefixed to them; and almost all the Orders have an artificial analy- 

 sis of the Genera comprehended under them, the use of which will be ex- 

 plained. For the examination of minute flowers, or parts of a flower, a good 

 magnifying glass is necessary. 



In the choice of specimens for analysis, those in full bloom should always 

 be preferred. Beginners will do well to select those flowers which have their 

 parts pretty large and well defined, such as the Rose and Lily ; but those which 

 are rendered double by cultivation should always be avoided, for their essential 

 organs (357) being changed to petals, it becomes extremely difficult to identify 

 them. In getting specimens, it is best to examine and see if the flowers are 

 perfect (874). If they are not, both the staminate and pistillate flowers should, 

 if possible, be obtained. 



Having procured a specimen, as of the Wild Rose, we proceed in our ex- 

 amination, finding that it has a proper flower, with proper stamens and pistils, 

 and thus obviously belongs to Pbienogamous plants. The stem being distin- 

 guished into pith, wood, and bark, would be sufficient to determine it to be an 

 Exogen, which is further confirmed by the net-veined leaves (269), and the 

 sepals and petals in fives, a number never found in Endogens. On all these 

 grounds we may safely conclude that our plant is an Exogen. Examining still 

 further, we find that the ovules are not arranged on the open surface or margin 

 of a scale, and therefore conclude that the plant belongs to Angiosperms. This, 

 also, is confirmed by the fact that the Cone-bearing trees, to which the Rose 

 does not belong, alone constitute the sub-class, Gymnosperms. 



Having thus ascertained that our plant belongs to the class Exogens, and the 

 sub-class Angiosperms, we turn to the description of the Orders to determine 

 its place there. The parts of the corolla are distinct ; but we are not yet certain 

 that it belongs to Polypetalae, for there are polypetalous plants jn both the other 

 sections. Referring to the Polypetalons plants not included under that section, 

 we commence examining the list. The first order, Ericaceae, has the " leaves 

 alternate, simple" which disagrees; for the leaves of the Rose, though altern 



14 



ate, are pinnate. " Aquifoliacese. Shrubs, petals 5," agrees. But the petals of 

 the Rose not being linear, we pass to Plumbaginncere. "Acaulescent herbs," 

 disagrees. We, therefore, pass to Oleaceae. But as " Stamens 2 " disagrees, we 

 proceed to the next. But as the Rose Is neither an evergreen shrub, nor monoe- 

 cious, it cannot belong here ; and, therefore, not being included in this excep- 

 tional list, we know that it belongs to I'olypetaliB proper. Passing to this sec- 

 tion, wo commence examining the Synopsis at the beginning, in order to find 

 its proper group. The description of Group 1 " Leaves flat, alternate; Sepals 

 distinct, and corolla regular," agrees ; but " Stamens inserted on the receptacle," 

 disagrees; for, on examination, we find the stamens inserted on the calyx. We, 

 therefore, pass to Group 2, but as these are all herbs, and the Rose is a shrub, 

 we go to the third, with which it disagrees, for the same reason. The fourth 

 group consists of " Herbs ; or Shrubs with yellow flowers." The Wild Rose is a 

 shrub, but its flowers are not yellow; therefore we proceed to Group 5. This 

 group has the " leaves alternate," which agrees, and " 20 or more stamens not 

 inserted on the calyx," which disagrees. The sixth Group includes only Herbs, 

 or Suffmticose plants, therefore the Rose cannot belong here. Group 7 

 " Trees, shrubs, or woody vines," agrees. But stamens 10 or less," disagrees, 

 and we pass to Group 8. Again the character, " Stamens 10 or less," disagrees ; 

 therefore we proceed to Group 9, where the character given is, " Leaves pre- 

 sent, not fleshy ; stamens more than 10." The Rose agrees in all these points, 

 and hence belongs to the ninth Group. Turning then to that Group in the 

 descriptions of the Orders, we commence examining the characters of the Or- 

 ders, till we find one with which our plant agrees. In this case it will be 

 Rosaceae. We then turn to Rosaceae in the Flora, and examine the Synopsis of 

 the genera, to find the genus. 



Sub-order 1. Amygdaleie has the "calyx free from the ovaries." This 

 agrees ; for what appear to be bony seeds, are, in reality, ovaries connected 

 each with a single pistil. "Style 1." This disagrees; for there are many styles 

 in the Rose. Therefore we pass to the second Sub-order, Rosaceae-proper, the 

 description of which agrees perfectly ; for the calyx is free from the ovaries, the 

 styles are many, the fruit consists of achenia, and the plant is a shrub. 



We now go to the first Section, designated by a *. " Fruit follicular." This 

 disagrees ; and we pass on to the second Section, designated by **. " Fruit 

 consisting of achenia, not inclosed in the calyx tube," disagrees ; for the ache- 

 nia are inclosed in the calyx tube. This forms the character of the third Sec- 

 tion, marked by ***, to which we now pass, consequently our plant belongs 

 here. The first genus, Agrimonia, consists of herbs with a dry turbinate calyx 

 tube, covered with hooked bristles. But the Rose is a shrub with a flexhy 

 calyx tube, either smooth or covered with straight bristles; therefore it cannot 

 belong here. Comparing it with the character of the next genus, Rosa, we find 

 a perfect agreement ; for it has the calyx tube fleshy in fruit, the achenia bony, 

 and is a prickly shrub. 



We turn to the genus Rosa, and after examining the generic character, in 

 order to become more familiar with it, we commence reading the descriptions 

 of the species, until we find one with which our plant entirely agrees. 



Such is the mode of analysis adopted in this work. But when we already 

 know the order to which a plant b^Jongs, we have only, by the same process 

 described above, to trace out Its genus and species. 



If the plant is an Endogen, we can go to the Synopsis at once, and determine 

 its group, and then its order ; but if it be an Exogen, we must, in all cases, de- 

 cide, in the manner illustrated above, whether it belongs to the section indi- 

 cated by its corolla, before we consult the Synopsis. If we find that it agrees 

 with the character of any order included under that list of exceptions, all we 

 have to do is to turn to the proper order and find the genus as before. It 

 should be stated here, that in all these analyses, Orders and Genera are some- 

 times divided : and in this case, any character given does not necessarily apply 

 to all the plants belonging to the order or genus, but only to those under con- 

 sideration. Thus the character given to some of the apetalous genera in Ra- 

 nunculacene, may not apply to all the polypetalous genera. 



In determining whether a flower oe monopetalous or not, you must not 

 consider it polypetalous because the segments appear distinct; but you must 

 pull them of? and see if they are not connected at the base. 



There are a few tribes of plants which (lifter so much from the usual forms, 

 that it seems best to explain their structure here, that the beginner may find no 

 difficulty in their analysis. Thus if we take the flower of a Dandelion, not being 

 acquainted with its peculiar structure, we might naturally suppose it poly]>eta- 

 lous ; but it really consists of a large collection of little flowers, each of them 

 having its own monopetalous corolla, which, in the present case, takes the form 

 of a strap. If we examine one of these little florets carefully, we can see that it 

 has all the parts of a flower, as perfectly developed as any other. On the out- 

 side it has a ring of hairs, or pappus, which represents the calyx. Then comes 

 the strap-shaped corolla; and from its tubular base arise the stamens, five in 

 number, united by their anthers, and forming a hollow tube, through which 

 the style projects. 



In the Thistle, again, the same structure exists, except that the corolla takes 

 the form of a tube, five-parted at the top. In the Ox-eyed Daisy, so common 

 in pastures, these two forms are combined. The central portion of the flower is 

 tubular, while on the outside we have a row of strap-shaped florets. In this 

 form, the head of flowers at the first glance bear a strong resemblance to the 

 flower of a polypetalous plant, the outer border of ligulate florets representing 

 the corolla, and the central tubular flowers the stamens and pistils. The begin- 

 ner should, therefore, remember that all flowers formed after the model of the 

 Dandelion, the Thistle, or the Daisy, are not polypetalous, but really collec- 

 tions of monopetalous flowers. 



The Milkweed family, also, have a curious structure. The calyx and deeply 

 5-parted corollas are reflexed, and 5 cucullate processes, called collectively the 

 crown, form the most showy portion of the flower. Alter removing this crown 

 we come to the stamens, which are five, and united by their filaments into a 

 tube, inclosing the pistil. Each anther is two-celled, each cell containing a 

 mass of coherent pollen. The two nearest pollen-masses in the cells of two ad- 

 jacent anthers, are connected together by a thread, and attached by it to one of 

 the five glandular angles of the stigma. Soon, generally through the agency of 

 insects, the pollen-masses are detached from the cells, and hang in pairs from 

 the stigma, as in fig. 19, Plate XXV. A similar structure is found in the Or- 

 chidaceie, or Orchis family, except that the 8 stamens are consolidated with 

 the pistil into a single column, and only one or two of the anthers are present 

 and fertile. The structure of both the pollen-masses in most of their species, 

 and the mode of their attachment to the stigma, is nearly the same. 



