142 STUDY OF COMMON PLANTS. 



II. Beginning with the lowest inflorescence, study care- 

 fully the individual flowers. Note first that each flower 

 is borne in the axil of a bract or scale. Describe the latter 

 as to form, color, and structure. 



III. Each flower is further protected by a sac called the 

 perigynium. Examine this, observing critically its form 

 and surface, venation, and the long beak terminating above 

 in two sharp teeth. 



IV. Open the perigynium and examine the pistillate 

 flower. It consists of a single pistil, which in some species 

 of Carex has two stigmas with a lenticular ovary, caryopsis, 

 while in others the caryopsis is triangular, and the stigmas 

 are three in number. Which do you find to be the case in 

 this species ? 



V. Taking younger specimens, examine the uppermost 

 (staminate) spikes. How do they differ in external 

 features from the pistillate ones ? Is each flower sub- 

 tended by a scale ? Does it have a perigynium ? How 

 many stamens are there ? 



VI. From the observed facts, what do you infer as to 

 the mode of fertilization ? 



RELATIONSHIP. 



A number of other species should, if possible, be com- 

 pared with the one just studied. Carex lupulina, utricu- 

 lata, stricta, gracillima, laxiflora, Pennsylvania, rosea, etc., 

 are of common occurrence and suitable for such a com- 

 parison. The beginner will do well to heed Professor 

 Bailey's remark to the effect that this is " an exceedingly 

 critical genus, the study of which should be attempted 

 only with complete and fully mature specimens." After 



