102 



THE STAMENS, OR ANDRECIUM. 



502. Staminodia, or sterile filaments with abortive anthers or none, occur singly 

 in many of the Figworts and Labiates, or in entire whorls next within the petals, 

 alternating with them, as in loose-strife ; in all cases restoring the symmetry of the 

 flowers. They are generally reduced in size, as in Scrophularia, rarely enlarged, as 

 in beardtongue (Pentstemon). 



503. The number of the stamens is said to be definite when not ex- 

 ceeding twenty, as is sometimes definitely expressed by such terms as 

 follow, compounded by the Greek numerals, viz., monandrous, having 

 one stamen to each flower ; diandrous, with two stamens ; pentandrous, 

 with five stamens. If the number exceeds twenty, it is said to be in- 

 definite (denoted thus, co ) or polyandrous. 



504. The position or insertion of the stamens (§ 463) maybe more 

 definitely stated here, as hypogynous, on the receptacle below the ovaries ; 

 perigynous, on the calyx around the ovary ; epipetalous, on the corolla, 

 as in Phlox ; epigynozis, on the ovary at its summit, aud gynandrous 

 (yvvij, pistil, dvdpeg, stamens) on the pistil, that is, when the stamens 

 are adherent to the style, as in Orchis. 



505. Inequality in length is definitely marked in two cases, as 

 tetradynamous (rerpag, four, diiva/iig, power) when the stamens are 

 six, whereof four are longer than the other two, as in all the Crucifers; 

 didynamous, where the stamens arc four, two of them longer than the 

 other two, as in all the Labiates, etc. 



366 365 364 363 862 



362, Collinsia verna: / a flower enlarged, cut, showing the slightly didynamous stamens, etc. 

 868, Stamens (diadelphous) of a Leguminous plant. 364, Stamens (syagenecious) of a Com- 

 posite ; /, filaments distinct ; a, anthers united ; *, stigmas revolute, etc. 365, Tetradynamous 

 ■tamens of a Crucifer. 366, Gynandrous column of Cypripedium ; o, ovary; r, torus; «, sterilo 

 stamen ; a, two pollinia ; c, stigma. 



506. Cohesion is as frequent with stamens as with petals. They 

 are monadelphous (ddeX(f>6g, a brother) when they are all united, as in 

 mallow, into one set or brotherhood by the filaments ; diadelphous in 

 two seta, whether equal or unequal, as in pea, squirrel-corn ; polyadel- 



