THE MINT FAMILY. 217 



III. Construct a diagram of the flower. Consult Eichler, 

 Bluthendiagramme, for diagrams and theoretical discussion 

 of the morphology of the flower of the Labiatse. 



IV. Examine the flower with reference to the way in 

 which fertilization is accomplished. 



1. Notice the spots and lines on the lower lip of the 



corolla. Examine different specimens and ascer- 

 tain whether they are constant in position. Are 

 they placed so as to serve as path-pointers ? 



2. Using a needle or bristle, imitate the action of an 



insect inserting its proboscis so as to extract the 

 nectar. Would it be likely to come in contact 

 with anthers or stigma, or both ? 



3. If practicable, examine flowers, from different locali- 



ties, and compare them as to size, position of the 

 anthers, and other features. 1 



4. Nepeta is reckoned by Miiller among the genera in 



which, for at least some of the species, self-fertili- 

 zation has become impossible. Does this appear 

 to be the case with Nepeta Grlechoma ? 



V. Compare, if they can be obtained, the highly modi- 

 fied flowers of Sal via, either those of the common sage, or 

 of species cultivated in conservatories. 2 



RELATIONSHIP. 



Examine as many of the following species as practicable, 

 comparing them with ground-ivy, and noting all common 

 characters. 



Catnip, Nepeta Cataria, L. 



1 Cf. Botanical Gazette, I, p. 41, II, p. 118 ; Miiller, Fertilization of 

 Flowers, p. 484. 



2 Cf. Sachs, Physiology of Plants, p. 794 ; Muller, I.e., p. 477 etseq. 



