586 



BOTANY 



PART II 



Teak -tree of the East Indies, yields a wood highly valued for shipbuilding and 

 other purposes. Verbena Aubletia is a common garden plant. 



Family Labiatae. — Ovary deeply eour-lobed, bicarpellary, four- 

 chambered, with G"XN0BASIC style (attached to the base instead of to 

 the summit of the ovary) ; fruit a four-partite schizocarp with four 



Fig. 575. — Floral diagram of 

 Lamium {Labiatae). 



nutlets. Herbs and small 

 shrubs with quadrangular 

 stems and opposite leaves ; 

 inflorescences dichasial 

 (Figs. 575-577). 



The Labiatae con- 

 stitute one of the most 

 natural families of the 

 vegetable kingdom. The 

 quadrangular stems and 

 decussate leaves give the 

 plants of this family 

 a distinctive character, 

 which is enhanced by 

 their odour and general 

 hairiness. The aroma so 

 characteristic of many 

 species is due to the 

 presence of an ethereal 

 oil secreted by small 

 glandular hairs scattered 

 over the surface of the 

 stems and leaves. Not 

 less characteristic of this 

 family is the apparent disposition of the short-stalked flowers in 

 whorls, but which in reality represent axillary scorpioid cymes some- 

 times termed verticillasters. The separate inflorescences often become 

 aggregated in terminal heads and spikes, as in the Thyme and Pepper- 

 mint. The calyx (Fig. 577) is gamosepalous and five-toothed. The 

 corolla is usually bilabiate, with two lobes in the upper lip and three 



Fig. 576.— Melissa officinalis.— Officixal. (After Bero 

 and Schmidt, £nat. size.) 



