TAMAIUX GALLICA. 423 



these two species ; I am now however inclined to think that 

 I named them wrongly in that work; subsequent investiga- 

 tions having led me to consider the southern form as the 

 T. Gallica, Linn., and that to which I formerly gave this name 

 as an unregistered species confounded with it. 



In order to establish this fact, it will be necessary to see 

 what has been previously written concerning these plants, 

 and more particularly as to their hypogynous disk considered 

 as a means of distinction and classification. The older bota- 

 nists seem to have paid no attention to this organ, and even 

 in later times a most acute observer, M. A. de St Hilaire, in 

 his treatise on the central Placenta, slightly alludes to it only, 

 when treating of the T. Germanica, but overlooks it in tiie T. 

 Gallica, (Ann. Mus, vol. ii. p. 207,) and affirms that the 

 stamens are perigynous.* It was reserved to Professor 

 Ehrenberg in his well-known observations on this family 

 (Linnaea 1827, p. 251,) to show its importance, and to call 

 the attention of botanists to its form, in the different species 

 which compose the genus. He considers it as a scutelliform 

 gland, in whose dentated margin the stamens are inserted, so 

 that two of the teeth of the gland like two shafts receive each 

 filament between them. Thus there is a regular proportion 

 between the stamens and the teeth of the gland, the teiran- 

 drous species having eight, the pentandrous ten, and the poly- 

 androus many teeth, and hence are derived the subgenera Oli- 

 gadenia, Decadenia, and Polpadenia, I am inclined to take a 

 slightly different view of this disk, believing it to be composed 

 of distinct glands or staminodes, analogous in their nature to 

 those of Crassulacea;, the marginsof which, united with the bases 

 of the filaments inserted between them, form together a single 

 cupule. The structure of Trichaunis ( Trkhurus?) ericoides, 

 Wight and Arnott, where the filaments, distinctly visible by 



* In this remarkable treatise, M. A. de St Hilaire first established the 

 characters of the group which he calls Tamaricinece, though the name 

 written afterwards TamariscinecB, by M. Desvaux, has been adopted by 

 all subsequent writers. It is clear, however, that it is to the former, and 

 not to M. Desvaux, that the foundation of the order should be attributed- 



