178 



I\IANUAL OF BOTANY 



(fig. 364) there are two such valves ; in plants belonging to the 

 Laurel family (fig. 365) there are two or four, according as the 

 anthers have two or four loouli. 



We may now consider the andrceoium as a whole from the 

 point of view of the relations of the stamens to each other, and 

 to the other whorls of the flower, noting the following points : — 

 1. ISfumber ; 2. Insertion or Position ; 3. Union or Cohesion ; 

 4. Belative Length. 



1. Number. — The number of the stamens is subject to great 

 variation, and several terms are in common use to indicate such 

 modifications. In the first place, certain names are applied to 

 define the number of the stamens when compared in this re- 

 spect with the component parts .of the floral envelopes. Thus 



FiCf. 364. 



Fig. 364. Autberof Barberry (Berberts 

 vulgaris}, opening by two valves. 

 Fig. 365. Stamen of a species of 

 Laurus. /. Filament, witli two 

 glands, gr, g, at its base.^ I, I. Loculi, 

 of which there are four. v. Valves. 



when the stamens are equal in number to the sepals and petals, 

 the flower is said to be isostemonous, as in the Primrose ; when 

 they are unequal, as in the Valerians (figs. 820 and 321), the 

 flower is aniaostemonous. When greater accuracy is required 

 in the latter case, we say ddplostemonous, if the stamens are 

 double the number, as in the Stonecrop ; meiostemonous, if fewer 

 in number, as in the Lilac ; and polystemonous, if more than 

 double, as in the Rose. 



Secondly, the flower receives different names according to 

 the actual number of free stamens it contains, without reference 

 to the number of parts in the outer whorls. This number is 

 indicated by the Greek numerals prefixed to the termination 

 ■androiis ; thus, a flower having onestamenis wionnjirf/OMS, two 

 diandrous, aiirl so on. 



