Respiration^ Digestion, and Fermentation. 109 



ascertain exact location of nectarial organs. A large number 

 will be found in floral structures. Well-developed nectaries 

 may be found outside the floral circles in Passiflora, Cassia, 

 Ricinus, and many species grown in conservatories. Make 

 an examination of the structure of the nectaries. Draw a 

 section made at right angles to the secreting surface, and note 

 structure of 

 secreting 

 cells. Ascer- 

 tain rate of 

 secretion by 

 removing the 

 nectar from a 

 gland and 

 noting length 

 of time neces- 

 sary for its re- 

 pl ac e ment. 

 Carefully re- 

 move the nec- 

 t a r from 

 another gland, 

 and then wash 

 well with dis- 

 tilled water, 

 and wipe dry 

 by means of 

 a minute por- 

 tion of linen cloth, 

 secretion? 



118. Action of glandular hairs Examine the glandu- 

 lar hairs of the pansy (Viola tricolor], horse-chestnut {&scu- 

 lus], Primula Sinensis, hop {Humulus lupulus}, and note struc- 

 ture of the glandular organ, and make various tests, including 



Fig. 79. Diagram of flower of Narcissus. /, nectary; *, 

 excreted nectar. After Schniewind-Thies. 



What effect does it have on the rate of 



