98 THE PHENOMENON OF 



sometimes triandrous,* also by the Irideae, Graminacese 

 and CyperacesBjt Alisma and Actinocarpus,\ Cerastium 

 semidecandrum, and tetrandrum, Mcenchia quafernella, 

 the tetrandrous species of Sac/ina, the pentagynous 

 Campanulacese, e. ff.. Campanula Medimn,^ Drosera,\ 

 Tainarix,% Viola, &c. On the other hand, an outer 

 circle of stamens is abortive in Triglocldn palusfre, while 

 in Tr. maritimum both circles are fully developed ; in 

 most of the digynous Solanacese {i. e., -wi^h two carpels), 

 in like manner, while in Nicotiana quadrivalvis the fruit 

 becomes four-chambered, by the development of both 

 circles ; moreover, in most of the Gentianese and 

 Apocynese, the Scrophularinese and Labiatse, the genera 

 of Rutacese with a double circle of stamens, the digynons 

 and trigynous Alsinece and SilenecB, as well as the penta- 

 gynous genera Malachium and Agrostemma.** 



An inner circle of stamens vanishes, together with an 

 outer circle of carpels, for instance, in Stellaria media 

 {pentandra) , in most of the Diosmese, Cneormn, Celas- 

 trinese, Ludwigia, and Isnardia, Circtsa (?),tt Hederacese, 

 Umbelliferse, &c. It is probable that in the Polygoneee 

 there is a suppression of li to 2 circles of stamens, and 

 one circle of carpels. In Rosacese, Pomacese, Amygda- 

 linese, Myrtacese, and Philadelphus, there is certainly 

 a suppression of several circles of stamens at the transition 

 to the fruit ; probably also we ought to assume two abor- 

 tive circles between the stamen-formation and the fruit 

 in the flowers of the Papilionacese. A glance back over 



* Juncus supinm is ordinarily triandrous, the variety which is held as 

 /. nigritellus, Don, is hexandrous. 



t At least in the CypemicB, the CaHcintE may be different ; see below. 



% Alisma and Aetinocarpus are rudimentarily enneandrous, like Butomus. 



\ The suppressed circle of stamens appears developed in the douMe 

 Campanula Medium of gardens. In this case the first circle of stamens 

 becomes the inner corolla, the abortive circle the circle of stamens. The 

 form and arrangement of the carpels remain unchanged. 



II Both circles are developed in Drosophyllum. 



^ In Myricaria {Tamarix germanica, L.) both circles are developed 



** See the 'Flora,' 1843, No. XXII, et seq. 



ft See the 'Flora,' 1835, I, 179. 



