STAMENS. 



61 



order of Primulacea-y in whicli the regular calyx is present. 

 This arrangement may easily he accounted for upon tlic ahove 

 supposition; and it receives contirmation from the fact, that 

 some plants having twice as many stamens as petals, and hav- 

 ing the appearance of heing in a single ro\r, yet half of them 

 are alternately longer than the othcM* half. This occurs in the 

 O.xalis giving prohahility to tlie supposition that the five short 

 stamens of the Oxalis were prevented from being developed 

 as perfectly as the other five, and had they been entirely pre- 

 vented we should thus have had an arrangement similar to the 

 Lysimach'ta with the opposite stamens. 



The number of stamens is generally the same as the petals 

 or lobes of the corolla, or a mtiltiple of the number. 



9'J. Whatever may be the ap|)arent origin of the stamen 

 its real origin is always the same, that is, 'oetween the base of 

 the petals and that of the ovarium. Tiieir apparent origin 

 varies remarkably, sometimes aj)pcaring to rise from the calyx 

 or corolla, (fig. 90,) wjicn they are said to he 2)erigynous ; at 



others thev arise from the pistil (fig. 91) itself and are said to be 

 epigynous, or from under tl»e pistil, their true origin, and called 

 hypogymms, (tig. 92.) 



93. Staniens are oficn united by their filaments, forming a 

 tube, as in the Mnlva, when they arc said to be inomidcJpliouft^ 

 (fig. 9:i,) or in one brotherhood. In other cases into two >ets, 

 when they are said to be diadelphous (fig. 94.) as in the Pea. 

 If into several sets the term polydclphous is applied, (fig. 90.) 

 as in some Hvpericums. 



If the stamens j)roj«ct beyond the corolla, they arc said to 

 be exserted, and included when shorter than the corolla. 



