240 NORTH AMERICAN SPECIES OF JUNCUS. 
naviculate, more herbaceous, more strongly ribbed and sharper pointed ; the latter more delicate; 
with a wider membranaceous margin, flat or slightly concave, but not naviculate, and more fre- 
quently obtuse or only mucronate, but more variable in their outline than the exterior ones. The 
sets of sepals are either equal in length, or one exceeds the other, but neither their proportion nor 
the form of the inner sepals offers perfectly reliable characters in all species ; in some they are more 
constant, while in others they vary considerably. In examining dried and even living specimens, 
the error of mistaking an involute sepal for an acute one must be avoided,— an error into which 
even careful botanists have sometimes fallen. The nerves of the sepals, which are of such diagnostic 
importance in Graminew and even Cyperacec, are of minor value in Jwnei, as they vary considerably 
in different forms of the same species. 
Stamens. — E. Meyer had already paid attention to the number of stamens and their proportion, 
and in many species valuable characters are derived from them, but they alone cannot constitute 
specific distinction. They are generally persistent, which permits us to examine them in all stages 
of development of the flower and fruit; only in J. Smithti and in J. Remerianus the anthers fall 
away early and the filaments only persist. The number of stamens is normally six, but in many 
(principally American) species, it is, by suppression of the inner circle, reduced to three; those three 
stamens stand, therefore, before the outer sepals and at the angles of the ovary or capsule. We have 
only two species in which their number regularly varies between three and six, J. Buckleyi and J. 
caudatus ; in them the inner circle of stamens is incompletely present. In many triandrous species 
we find occasionally a fourth or fifth stamen, and that often smaller than the rest; but where both 
circles are regularly developed, I have never seen them unequal in size or shape, which we notice so 
often in other allied families. 
The proportion of stamens and sepals, and of anthers and filaments, is often very con- [429] 
stant, but in some species they vary very much, as may be seen in J. scirpoides, the different 
forms of which bear stamens of different length and anthers of different size, without exhibiting 
other characters of sufficient specific value. 
n a rare form of J. Remerianus I find both circles of stamens suppressed or rather unde- 
veloped and in a rudimentary state, so that those plants become unisexual. Corresponding male 
plants may perhaps yet be discovered. 
Filaments are always present; in some species they are very short, in others elongated, in all 
dilated at base, and, at least in the hexandrous ones, more or less united. Their base, which in the 
young flower adheres to the base of the pistil, after fecundation remains attached to the base of 
the sepals. 
The shape of the anthers is of slight importance; they are longer or shorter, sane or oblong, in 
some species pointed or cuspidate, in most others obtuse or emarginate, more or less sagittate at 
base; but these characters show little constancy. 
Pistil.—The pistil exhibits great differences in its form, and furnishes good and generally con- 
stant characters. The ovary is obtuse or acute, gradually or abruptly elongated into the style. tee 
organ is often very short, but in many species it has the length of the ovary, or even exceeds it ; 
a few species only it is variable, ¢. g. in J. seirpoides, which in this as in most other organs pas a 
degree of variability scarcely seen in any other species. The stigmas are longer or shorter than the 
ovary with the style, always (except in Juncellus) three in number, very slender and more or less 
twisted ; in J. acutus they are short and thick, and in J. stygius, as already Linneus remarks, short 
and eared. In just expanding flowers the length of the stamens is often equal to that of the 
ovary and style together, so that the stigmas only emerge from between the anthers, or they are 
equal to the ovary alone, when the whole style with the stigmas protrudes over the anthers. 
Capsule. — The capsule is diagnostically one of the most important organs in Junci. It varies 
from globose to ovate, obovate, prismatic, pyramidal or subulate, terete or angular, retuse, obtuse or 
