ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 



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by a shield-like head composed of a single layer of eight to sixteen 

 radiating cells. In A. armata the head is always vertically elongated 

 and never shield-like. In A. pycnantha (Fig. 4) the hairs are elon- 

 gated and clnb-shaped, and have probably arisen from the same type 



FiG.-l. — Mature gland of Acacia 

 mpicola, showing uniseriate 

 stalk and inflated head-cell. 

 X 230. 



Fig. 2. — Surface view of gland of A, 

 verniciflua. x 230. , 



Fig. 3. — Mature gland of A . verniciflua. x 230. 



Fig. 4. — Glandular hair from base of 

 phyllode of A. pycnantha. 

 X 200. 



Fig. 5.^Glandular hair of 

 Myopontmserratum. x 280. 



as that of A. armata. They are restricted to the zone at the base of 

 the phyllode. 



In the Composite the most common type of gland is shortly stalked 

 and has a head divided by a median vertical wall into two rows of cells. 

 Two methods of development are seen in Ixodea achiUeoides and 

 Helichrysum semipapposum . 



