102 HOW PLANTS ARE CLASSIFIED AND STUDIED. 



Turn now to the account of this family, and read over the descriptive marks 

 given, to see if you have been led to a right conclusion. The description agrees, 

 as far as it goes. Knowing the family, you now ask, — 



To what genus of this family does the plant belong ? The genus gives the 

 principal name of the plant ; so this is the same as asking, What is the plant's 

 name ? Now, in every family which has several genera or kinds under it, we have 

 a key to the genera, like that which we have just used under the class to find out 

 the family. Try the key, then, under this family, to find out the genus. 



This key begins with a pair of lines, viz. " Climbing plants," &c., and " Not 

 climbing," &c. Our plant agrees with the latter. Under this, in the next rank, 

 is a pair of lines, beginning with " Pistils " (the second line of the pair is the sixth 

 on p. 113). You perceive that our plant falls under the first. Under this is the 

 line beginning " Petals none." Our flower has petals ; so pass on to the other one 

 of the pair, which is the fifth line on p. 113. This reads "Petals present as well 

 as sepals, the latter falling oflF early " (which agrees) ; and leads ' to the name of 

 tho genus, i. e. " {Ranunculus) Crowfoot." 



The first name, in parentheses and in Italic type, is the scientific or Latin name 

 of the genus ; the other, in small capitals, is the popular English name of the genus. 

 When we have only one species to the genus, we do not in this book proceed 

 farther. But there are many Crowfoots, so you next inquire, — 



What is the species ? Look on, till you come to the name of the genus in dark 

 letters, on p. 114. Here a few more marks of the Crowfoot genus are given; and 

 ihen the marks of ten common species of Crowfoot follow, under several heads. We 

 are supposed to have in our hands one of the two large yellow-flowered species, com- 

 monly called Buttercups. Compare the specimens with the divisions marked by 

 stars. It cannot belong to that with one star, for the petals are not white ; it does 

 belono- to that with two stars, for the petals are j'ellow, and bear a little scale on 

 the inside just above the bottom. Under this are two divisions, marked with dag- 

 gers. Not growing under water, our plant belongs to that marked n— +-. Under 

 this are two further divisions, marked ++ and ++ ++ : our plant, having the " petals 

 much longer than the calyx," belongs to the second of these. • 



Under this head are four species. The English name is given at the beginning 

 of the line, in small capital letters ; a short description follows, and the scientific or 

 Latin name is appended, in Italic letters, at the end. Here the R. of course stands 

 for Ranunculus. A comparison with the description will show which species it ia 



