350 ME. F. N. WILLIAMS OK THE GENUS DIAffTHFS. 



nate or mucrcnate, and either ciliolate, smooth, or membranous 

 at the edges. The whole of the tube of the calyx is multistriate, 

 and the nerves are well-marked and parallel, of which there 

 are 7, 9, or 11 (3 in P rotifer as t rum) to each lobe. The fasciculus 

 of nerves to each lobe is bounded by a membranous part markiug 

 the division into sepals. When th&s stems are pubescent the 

 calyx is usually more so. In very rare instances, as in D. Cyn, 

 it is covered with small warts, and the striation is obscure. 



Petals. — Each of the two parts of the petal is quite distinct, 

 and this constitutes really the only generic character which 

 separates Dianthns from Tunica. The claw is very pale; 

 the blade is bright-coloured, but frequently paler on the under 

 surface. Chorisis in the petals is reduced to its simplest form, 

 viz., a capillary outgrowth at the junction of the blade with the 

 claw, and is the homologue of the corona in Silene and the ligula 

 in Lychnis. This bearded condition of the petals serves to dis- 

 tinguish groups of species. The segmentation of the blade to 

 such an extent as is seen in the fimbriate species is very unusual 

 in flowers ; and the retuse margin in D. glumaceus is the least 

 specialized modification of the laminar margin. In the same 

 species petals may be entire and dentate, but they are never 

 entire and fimbriate or dentate and fimbriate. As to the degree 

 of incision of the petals which should place a plant among the 

 fimbriate species, I think no sharp line can be drawn. They 

 should certainly include those whose petals are incised halfway 

 or more from the margin to the throat, probably also all those 

 with the blade incised to one-third of its depth. In those that 

 are not so deeply incised we have to consider the relative 

 length and breadth of the teeth or fimbria themselves, apart 

 from the undissected intermediate area and the degree of their 

 acumination. 



Stamens. — The dichogamous development of the essential 

 organs is usual throughout the genus. In the individual flowers 

 of the same plant the reproductive organs are almost invariabl) 

 proterandrous, but this proterandry takes place at different times 

 in the different flowers of the same plant ; this is well seen in D- 

 deltoides and D. liburnicus. This dichogamous mode of develop- 

 ment undergoes a certain modification to serve similar purposes 

 in D. Armeria and other species. Though proterandrous func- 

 tional activity is the form of dichogamy which generally obtains, 

 it is not so well marked in this plant ; consequently that modi 

 cation obtains which is adapted in other cases to intercrossing 



