ESSENTIAL ORGANS — STAMENS. 227 



the Fir, and in the Oycadacese, the stamens are to be regarded as single 

 male flowers, supported on scales ; being either a single stamen with 

 bilooular anthers, as in Pinus, or unilocular, as in Abies, or several 

 stamens united in an androphore, as in Taxus. In the genus Pinus 

 there are male cones composed of bract-like processes, bearing on their 

 lower side two parallel anther-lobes, beyond which a scale-like con- 

 nective extends. In the Yew and Cypress there is a peltate connec- 

 tive overhanging the anthers. In Oycads there are numerous anthers 

 on the lower surface of the scales of the male cones. 



Stamens occasionally become sterile by the degeneration or non- 

 development of the anthers, which, in consequence of containing pollen, 

 are essential for fertilisation ; such stamens receive the name of stamirir- 

 odia, or rudimentary stamens. In Sorophularia (fig. 378) the fifth 

 stamen, s, appears in the form of a scale ; and in many Pentstemons 

 it is reduced to a filament with hairs, or a shrivelled membrane at the 

 apex. In other cases, as in double flowers, the stamens are converted 

 into petals ; this is also probably the case with such 

 plants as Mesembryanthemum, where there is a multi- 

 plication of petals in several rows. In Persea gratis- 

 sima (fig. 357), two glands, g, are produced at the 

 base of the filament in the form of stamens, the 

 anthers of which are abortive ; the same thing is seen 

 in other Lauracese. In these cases the central perfect 

 stamen may be considered as representing the true 

 leaf, and the two staminodes or glandular bodies, the 

 stipules. Sometimes only one of the anther-lobes be- 

 comes abortive. In many unilocular anthers, the non- 

 development of one lobe is indicated by the lateral ^ g^g 

 production of a cellular mass resembling the connective. 

 In Salvias, where the connective is distractUe, one of the lobes only 

 is perfect or fertile (fig. 365, If), containing pollen, the other (fig. 

 365, Is) is imperfectly developed and sterile. In Oanna, in place of 

 one of the lobes, a petaloid appendage is produced. 



The stamens, in place of being free and separate, may become united 

 by their filaments (pp. 218, 219). They may also unite by their 

 anthers, and become syngenesious or synantherous (auv, together, yeveaig, 

 origin, avSriga, anther). This union occurs in Composite flowers, and 

 in Lobelia, Jasione, Viola, etc. 



Stamens vary in length as regards the corolla. Some are en- 

 closed within the tube of the flower, as in Cinchona, and are called 

 included (figs. 311, 312, 376) ; others are exserted, or extend beyond 

 the flower, as in Littorella, Plantago, and Exostemma. Sometimes 

 the stamens in the early state of the flower project beyond the petals, 



Fig. 378. Irregular corolla of Scrophularia, "with astaminodium, s, or abortive stamen, ia 

 the form of a scale. 



