LESSON 31.] HOW TO STUDY PLANTS. 187 



LESSON XXXI. 



HOW TO STUDY PLANTS: FURTHER ILLUSTRATIONS. 



538. BEGINNERS should not be discouraged by the slow progress 

 they must needs make in the first trials. By perseverance the 

 various difficulties will soon be overcome, and each successful anal- 

 ysis will facilitate the next. Not only will a second species of 

 the same genus be known at a glance, but commonly a second 

 genus of the same order will be recognized as a relative at sight, 

 by the family likeness. Or if the family likeness is not detected at 

 the first view, it will be seen as the characters of the plant are 

 studied out. 



531). For the sake of an example in the Gamopetalae, we take a 

 common Monkey-flower, whose yellow blossoms are to be found 

 almost everywhere in the Rocky Mountain region. 



540. A glance shows that the plant belongs to Series I., PII^NO- 

 GAMIA or FLOWERING PLANTS, while its closed ovary containing 

 ovules refers it to ANGIOSPERMJE. Its netted- veined leaves and 

 five-rnerous flowers make it plainly a DICOTYLEDON. 



The corolla being tubular below, theoretically regarded as 

 formed of five united petals, refers it to (p. xii.) Division II., GA- 



MOPETAL^E. 



The student is sometimes puzzled at first to tell how many petals 

 enter into the composition of a gamopetalous flower. Frequently 

 the distinct and regular lobes above make this very apparent, but 

 in the case before us the first impulse would be to say that the 

 corolla is made up of two blended petals, for it is a two-lipped 

 affair. An examination of each lip shows that the upper is two- 

 lobed, and the lower three-lobed, making five blended petals, 

 already suggested by the five teeth of the calyx. 



The two subdivisions of GAMOPETALAE, marked A and B, de- 

 pend upon the relative position of the ovary and other flower parts, 

 and, as our flower has a decidedly superior ovary, a choice is made 

 of B. 



There are three choices under B (1, 2, and 3), which depend 

 upon the number and position of the stamens with reference to the 

 petals. In our flower there are but four stamens, which charac- 

 ter would place it in the section marked 3. It would be well, 



