MR. F. N. WILLIAMS ON THE GENUS SILENE. 9 
(2) those species in which the capsular teeth are isomerous with 
the styles, and which comprise the genus Viscaria of Rohling. 
If species which have five styles are excluded from Silene, it 
would be better perhaps to include Polyschemone nivalis, Schott 
(Lychnis nivalis, Kit.), in Eudianthe, though Rohrbach in his 
monograph has preferred to retain this species as well as 
Agrostemma Ceeli-rosa* in Silene. As long ago as 1825, Robert 
Sweet, in discussing the affinities of the plant now known as 
Heliosperma alpestre, remarked that the genus Silene was very 
much overgrown, and threw out the suggestion that “those 
(species) with an inflated calyx will probably form another 
natural genus.” Though the disintegration of such genera as 
Szlene has not proceeded on the lines indicated by this distin- 
guished horticulturist, and though superficial and obvious 
characters such as the structure of the floral envelope have not 
been considered of generic importance, a study of essential 
characters in definite groups of species only emphasizes still 
more what Fries said, that it is a ‘‘ genus vastissimum undique 
ad reliqua radios emittens.” + 
Turning to the subtribe of Gypsophilex, we find that in the 
species of Vaccaria only are there dissepiments at the base of 
the capsule, and that Acanthophophyllum ¢ (with which should 
now be united Bunge’s genus Allochrusa) is alone distinguished 
from the others in having a subindehiscent capsule, and like 
Drypis opens irregularly by circumscissile rupture. These 
subsidiary characters only show how genera artificially or 
arbitrarily delimitated tend to intergrade with, even if they do 
not sometimes overlap, one another. It would be outside the 
scope of our subject to discuss the affinities of Saponaria and 
Gypsophila, though if one were sunk in the other, which would 
be quite feasible, the necessity for earmarking any characters 
as differential would be removed. A connecting link between 
Gypsophila and the Dianthes is Gypsophila ortegioides, Boiss., 
but what is to become of this species I do not know. It con- 
"stitutes the section Phryna in Boissier’s grouping of the 
oriental species; as the Greek name suggests an outcast, it 
might have to become the type of a new genus. Lastly, in the 
* Linn., Sp. Plantarum, ed. I, p. 436. 
t Flora (1843), I, p. 123. 
t For a recent revision of this genus, see an interesting and valuable 
memoir by M. Golenkin in Act. Hort. Petropolit., xiii (1898), p. 77. 
