342 FILAMENT ANTHER. 



always destitute of colour; but there are exceptions to both 

 these characters. In Fuchsia, for instance, the filaments are 

 red like the petals ; in Adamia they are blue ; in (Enothera 

 they are yellow ; and a return to the foliaceous state of which 

 they usually are a distinct modification is by no means rare. 

 (Plate IV. fig. 6. 8.). Thus the filament in Canna is undis- 

 tinguishable from petals except by its having an anther; 

 in the same genus and its allies, and in all Gingerworts 

 (Zingiberacese), the inner series of what seem to be petals 

 are modifications of filaments (see Vegetable Kingdom, pp. 162, 

 &c.) : and this is a very common circumstance in sterile 

 stamens. 



A remarkable modification of the filament has been 

 observed in Spironema fragrans. In that plant the epidermis 

 of this organ is excessively thin, hardly adheres to the tissue 

 below it, and incloses a bundle of spiral vessels too long for 

 the sheath of skin, so that, while the latter is straight and 

 even, the former are forced into a spiral direction for want of 

 room to straighten. 



The filament also varies in other respects : in Thalictrum 

 it is thickest at the upper end, or clavate (Plate III. fig. 23.) ; 

 in Mahernia geniculate (Plate III. fig. 25.), in Hertella 

 spiral, in Crambe bifurcate, in Anthericum bearded or stupose. 

 In some plants the filaments are combined into a solid body 

 called the columna, as in Stapelia, Stylidium (Plate IV. fig. 1, 

 2, 3.), Rafflesia, and others : this has in Orchids received 

 from Richard the name of gynostemium. 



Care must be taken not to confound the pedicel and single 

 stamen of the naked male flowers of Euphorbia with a fila- 

 ment, as was done by all writers, until Brown detected the 

 error. For modifications of filaments see Plates III. and IV. 



The Anther (Theca of Grew; Capsula, Malpighi; Apex, 

 Ray ; Testiculus or Teslis, Vaillant ; Capituhim, Jungius ; 

 Spermatocystidium, Hedwig) is a body generally attached to 

 the apex of the filament, composed of two parallel lobes or 

 cells (thecce, or coniothecce, or loculi,} containing pollen, and 

 united by the connective. It consists entirely of cellular tissue, 

 with the exception sometimes of a bundle of very minute 



